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authorLinus Torvalds <torvalds@linux-foundation.org>2018-01-31 14:31:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-01-31 14:31:10 -0800
commitb2fe5fa68642860e7de76167c3111623aa0d5de1 (patch)
treeb7f9b89b7039ecefbc35fe3c8e73a6ff972641dd /kernel
parenta103950e0dd2058df5e8a8d4a915707bdcf205f0 (diff)
parenta54667f6728c2714a400f3c884727da74b6d1717 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) Significantly shrink the core networking routing structures. Result of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf 2) Add netdevsim driver for testing various offloads, from Jakub Kicinski. 3) Support cross-chip FDB operations in DSA, from Vivien Didelot. 4) Add a 2nd listener hash table for TCP, similar to what was done for UDP. From Martin KaFai Lau. 5) Add eBPF based queue selection to tun, from Jason Wang. 6) Lockless qdisc support, from John Fastabend. 7) SCTP stream interleave support, from Xin Long. 8) Smoother TCP receive autotuning, from Eric Dumazet. 9) Lots of erspan tunneling enhancements, from William Tu. 10) Add true function call support to BPF, from Alexei Starovoitov. 11) Add explicit support for GRO HW offloading, from Michael Chan. 12) Support extack generation in more netlink subsystems. From Alexander Aring, Quentin Monnet, and Jakub Kicinski. 13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From Russell King. 14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso. 15) Many improvements and simplifications to the NFP driver bpf JIT, from Jakub Kicinski. 16) Support for ipv6 non-equal cost multipath routing, from Ido Schimmel. 17) Add resource abstration to devlink, from Arkadi Sharshevsky. 18) Packet scheduler classifier shared filter block support, from Jiri Pirko. 19) Avoid locking in act_csum, from Davide Caratti. 20) devinet_ioctl() simplifications from Al viro. 21) More TCP bpf improvements from Lawrence Brakmo. 22) Add support for onlink ipv6 route flag, similar to ipv4, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits) tls: Add support for encryption using async offload accelerator ip6mr: fix stale iterator net/sched: kconfig: Remove blank help texts openvswitch: meter: Use 64-bit arithmetic instead of 32-bit tcp_nv: fix potential integer overflow in tcpnv_acked r8169: fix RTL8168EP take too long to complete driver initialization. qmi_wwan: Add support for Quectel EP06 rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK ipmr: Fix ptrdiff_t print formatting ibmvnic: Wait for device response when changing MAC qlcnic: fix deadlock bug tcp: release sk_frag.page in tcp_disconnect ipv4: Get the address of interface correctly. net_sched: gen_estimator: fix lockdep splat net: macb: Handle HRESP error net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring ipv6: addrconf: break critical section in addrconf_verify_rtnl() ipv6: change route cache aging logic i40e/i40evf: Update DESC_NEEDED value to reflect larger value bnxt_en: cleanup DIM work on device shutdown ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile1
-rw-r--r--kernel/bpf/Makefile2
-rw-r--r--kernel/bpf/arraymap.c49
-rw-r--r--kernel/bpf/cgroup.c15
-rw-r--r--kernel/bpf/core.c409
-rw-r--r--kernel/bpf/cpumap.c31
-rw-r--r--kernel/bpf/devmap.c8
-rw-r--r--kernel/bpf/disasm.c63
-rw-r--r--kernel/bpf/disasm.h29
-rw-r--r--kernel/bpf/hashtab.c103
-rw-r--r--kernel/bpf/lpm_trie.c98
-rw-r--r--kernel/bpf/offload.c430
-rw-r--r--kernel/bpf/sockmap.c16
-rw-r--r--kernel/bpf/stackmap.c34
-rw-r--r--kernel/bpf/syscall.c214
-rw-r--r--kernel/bpf/verifier.c1451
-rw-r--r--kernel/events/core.c10
-rw-r--r--kernel/fail_function.c349
-rw-r--r--kernel/module.c6
-rw-r--r--kernel/trace/Kconfig9
-rw-r--r--kernel/trace/bpf_trace.c59
-rw-r--r--kernel/trace/trace_kprobe.c61
-rw-r--r--kernel/trace/trace_probe.h12
23 files changed, 2856 insertions, 603 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 172d151d429c..f85ae5dfa474 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -81,6 +81,7 @@ obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
obj-$(CONFIG_GCOV_KERNEL) += gcov/
obj-$(CONFIG_KCOV) += kcov.o
obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_FAIL_FUNCTION) += fail_function.o
obj-$(CONFIG_KGDB) += debug/
obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index e691da0b3bab..a713fd23ec88 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -9,9 +9,11 @@ obj-$(CONFIG_BPF_SYSCALL) += devmap.o
obj-$(CONFIG_BPF_SYSCALL) += cpumap.o
obj-$(CONFIG_BPF_SYSCALL) += offload.o
ifeq ($(CONFIG_STREAM_PARSER),y)
+ifeq ($(CONFIG_INET),y)
obj-$(CONFIG_BPF_SYSCALL) += sockmap.o
endif
endif
+endif
ifeq ($(CONFIG_PERF_EVENTS),y)
obj-$(CONFIG_BPF_SYSCALL) += stackmap.o
endif
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index ab94d304a634..b1f66480135b 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -49,27 +49,35 @@ static int bpf_array_alloc_percpu(struct bpf_array *array)
}
/* Called from syscall */
-static struct bpf_map *array_map_alloc(union bpf_attr *attr)
+static int array_map_alloc_check(union bpf_attr *attr)
{
bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
int numa_node = bpf_map_attr_numa_node(attr);
- u32 elem_size, index_mask, max_entries;
- bool unpriv = !capable(CAP_SYS_ADMIN);
- struct bpf_array *array;
- u64 array_size, mask64;
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size == 0 ||
attr->map_flags & ~ARRAY_CREATE_FLAG_MASK ||
(percpu && numa_node != NUMA_NO_NODE))
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
if (attr->value_size > KMALLOC_MAX_SIZE)
/* if value_size is bigger, the user space won't be able to
* access the elements.
*/
- return ERR_PTR(-E2BIG);
+ return -E2BIG;
+
+ return 0;
+}
+
+static struct bpf_map *array_map_alloc(union bpf_attr *attr)
+{
+ bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
+ int numa_node = bpf_map_attr_numa_node(attr);
+ u32 elem_size, index_mask, max_entries;
+ bool unpriv = !capable(CAP_SYS_ADMIN);
+ struct bpf_array *array;
+ u64 array_size, mask64;
elem_size = round_up(attr->value_size, 8);
@@ -112,12 +120,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
array->map.unpriv_array = unpriv;
/* copy mandatory map attributes */
- array->map.map_type = attr->map_type;
- array->map.key_size = attr->key_size;
- array->map.value_size = attr->value_size;
- array->map.max_entries = attr->max_entries;
- array->map.map_flags = attr->map_flags;
- array->map.numa_node = numa_node;
+ bpf_map_init_from_attr(&array->map, attr);
array->elem_size = elem_size;
if (!percpu)
@@ -327,6 +330,7 @@ static void array_map_free(struct bpf_map *map)
}
const struct bpf_map_ops array_map_ops = {
+ .map_alloc_check = array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -337,6 +341,7 @@ const struct bpf_map_ops array_map_ops = {
};
const struct bpf_map_ops percpu_array_map_ops = {
+ .map_alloc_check = array_map_alloc_check,
.map_alloc = array_map_alloc,
.map_free = array_map_free,
.map_get_next_key = array_map_get_next_key,
@@ -345,12 +350,12 @@ const struct bpf_map_ops percpu_array_map_ops = {
.map_delete_elem = array_map_delete_elem,
};
-static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr)
+static int fd_array_map_alloc_check(union bpf_attr *attr)
{
/* only file descriptors can be stored in this type of map */
if (attr->value_size != sizeof(u32))
- return ERR_PTR(-EINVAL);
- return array_map_alloc(attr);
+ return -EINVAL;
+ return array_map_alloc_check(attr);
}
static void fd_array_map_free(struct bpf_map *map)
@@ -474,7 +479,8 @@ void bpf_fd_array_map_clear(struct bpf_map *map)
}
const struct bpf_map_ops prog_array_map_ops = {
- .map_alloc = fd_array_map_alloc,
+ .map_alloc_check = fd_array_map_alloc_check,
+ .map_alloc = array_map_alloc,
.map_free = fd_array_map_free,
.map_get_next_key = array_map_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
@@ -561,7 +567,8 @@ static void perf_event_fd_array_release(struct bpf_map *map,
}
const struct bpf_map_ops perf_event_array_map_ops = {
- .map_alloc = fd_array_map_alloc,
+ .map_alloc_check = fd_array_map_alloc_check,
+ .map_alloc = array_map_alloc,
.map_free = fd_array_map_free,
.map_get_next_key = array_map_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
@@ -592,7 +599,8 @@ static void cgroup_fd_array_free(struct bpf_map *map)
}
const struct bpf_map_ops cgroup_array_map_ops = {
- .map_alloc = fd_array_map_alloc,
+ .map_alloc_check = fd_array_map_alloc_check,
+ .map_alloc = array_map_alloc,
.map_free = cgroup_fd_array_free,
.map_get_next_key = array_map_get_next_key,
.map_lookup_elem = fd_array_map_lookup_elem,
@@ -610,7 +618,7 @@ static struct bpf_map *array_of_map_alloc(union bpf_attr *attr)
if (IS_ERR(inner_map_meta))
return inner_map_meta;
- map = fd_array_map_alloc(attr);
+ map = array_map_alloc(attr);
if (IS_ERR(map)) {
bpf_map_meta_free(inner_map_meta);
return map;
@@ -673,6 +681,7 @@ static u32 array_of_map_gen_lookup(struct bpf_map *map,
}
const struct bpf_map_ops array_of_maps_map_ops = {
+ .map_alloc_check = fd_array_map_alloc_check,
.map_alloc = array_of_map_alloc,
.map_free = array_of_map_free,
.map_get_next_key = array_map_get_next_key,
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index b789ab78d28f..c1c0b60d3f2f 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -568,6 +568,8 @@ static bool cgroup_dev_is_valid_access(int off, int size,
enum bpf_access_type type,
struct bpf_insn_access_aux *info)
{
+ const int size_default = sizeof(__u32);
+
if (type == BPF_WRITE)
return false;
@@ -576,8 +578,17 @@ static bool cgroup_dev_is_valid_access(int off, int size,
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
- if (size != sizeof(__u32))
- return false;
+
+ switch (off) {
+ case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type):
+ bpf_ctx_record_field_size(info, size_default);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_default))
+ return false;
+ break;
+ default:
+ if (size != size_default)
+ return false;
+ }
return true;
}
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7949e8b8f94e..5f35f93dcab2 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -94,6 +94,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
fp->pages = size / PAGE_SIZE;
fp->aux = aux;
fp->aux->prog = fp;
+ fp->jit_requested = ebpf_jit_enabled();
INIT_LIST_HEAD_RCU(&fp->aux->ksym_lnode);
@@ -217,30 +218,40 @@ int bpf_prog_calc_tag(struct bpf_prog *fp)
return 0;
}
-static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn)
-{
- return BPF_CLASS(insn->code) == BPF_JMP &&
- /* Call and Exit are both special jumps with no
- * target inside the BPF instruction image.
- */
- BPF_OP(insn->code) != BPF_CALL &&
- BPF_OP(insn->code) != BPF_EXIT;
-}
-
static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta)
{
struct bpf_insn *insn = prog->insnsi;
u32 i, insn_cnt = prog->len;
+ bool pseudo_call;
+ u8 code;
+ int off;
for (i = 0; i < insn_cnt; i++, insn++) {
- if (!bpf_is_jmp_and_has_target(insn))
+ code = insn->code;
+ if (BPF_CLASS(code) != BPF_JMP)
continue;
+ if (BPF_OP(code) == BPF_EXIT)
+ continue;
+ if (BPF_OP(code) == BPF_CALL) {
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ pseudo_call = true;
+ else
+ continue;
+ } else {
+ pseudo_call = false;
+ }
+ off = pseudo_call ? insn->imm : insn->off;
/* Adjust offset of jmps if we cross boundaries. */
- if (i < pos && i + insn->off + 1 > pos)
- insn->off += delta;
- else if (i > pos + delta && i + insn->off + 1 <= pos + delta)
- insn->off -= delta;
+ if (i < pos && i + off + 1 > pos)
+ off += delta;
+ else if (i > pos + delta && i + off + 1 <= pos + delta)
+ off -= delta;
+
+ if (pseudo_call)
+ insn->imm = off;
+ else
+ insn->off = off;
}
}
@@ -289,6 +300,11 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
}
#ifdef CONFIG_BPF_JIT
+/* All BPF JIT sysctl knobs here. */
+int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON);
+int bpf_jit_harden __read_mostly;
+int bpf_jit_kallsyms __read_mostly;
+
static __always_inline void
bpf_get_prog_addr_region(const struct bpf_prog *prog,
unsigned long *symbol_start,
@@ -370,8 +386,6 @@ static DEFINE_SPINLOCK(bpf_lock);
static LIST_HEAD(bpf_kallsyms);
static struct latch_tree_root bpf_tree __cacheline_aligned;
-int bpf_jit_kallsyms __read_mostly;
-
static void bpf_prog_ksym_node_add(struct bpf_prog_aux *aux)
{
WARN_ON_ONCE(!list_empty(&aux->ksym_lnode));
@@ -552,8 +566,6 @@ void __weak bpf_jit_free(struct bpf_prog *fp)
bpf_prog_unlock_free(fp);
}
-int bpf_jit_harden __read_mostly;
-
static int bpf_jit_blind_insn(const struct bpf_insn *from,
const struct bpf_insn *aux,
struct bpf_insn *to_buff)
@@ -711,7 +723,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
struct bpf_insn *insn;
int i, rewritten;
- if (!bpf_jit_blinding_enabled())
+ if (!bpf_jit_blinding_enabled(prog) || prog->blinded)
return prog;
clone = bpf_prog_clone_create(prog, GFP_USER);
@@ -753,13 +765,16 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
i += insn_delta;
}
+ clone->blinded = 1;
return clone;
}
#endif /* CONFIG_BPF_JIT */
/* Base function for offset calculation. Needs to go into .text section,
* therefore keeping it non-static as well; will also be used by JITs
- * anyway later on, so do not let the compiler omit it.
+ * anyway later on, so do not let the compiler omit it. This also needs
+ * to go into kallsyms for correlation from e.g. bpftool, so naming
+ * must not change.
*/
noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
{
@@ -767,6 +782,137 @@ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
}
EXPORT_SYMBOL_GPL(__bpf_call_base);
+/* All UAPI available opcodes. */
+#define BPF_INSN_MAP(INSN_2, INSN_3) \
+ /* 32 bit ALU operations. */ \
+ /* Register based. */ \
+ INSN_3(ALU, ADD, X), \
+ INSN_3(ALU, SUB, X), \
+ INSN_3(ALU, AND, X), \
+ INSN_3(ALU, OR, X), \
+ INSN_3(ALU, LSH, X), \
+ INSN_3(ALU, RSH, X), \
+ INSN_3(ALU, XOR, X), \
+ INSN_3(ALU, MUL, X), \
+ INSN_3(ALU, MOV, X), \
+ INSN_3(ALU, DIV, X), \
+ INSN_3(ALU, MOD, X), \
+ INSN_2(ALU, NEG), \
+ INSN_3(ALU, END, TO_BE), \
+ INSN_3(ALU, END, TO_LE), \
+ /* Immediate based. */ \
+ INSN_3(ALU, ADD, K), \
+ INSN_3(ALU, SUB, K), \
+ INSN_3(ALU, AND, K), \
+ INSN_3(ALU, OR, K), \
+ INSN_3(ALU, LSH, K), \
+ INSN_3(ALU, RSH, K), \
+ INSN_3(ALU, XOR, K), \
+ INSN_3(ALU, MUL, K), \
+ INSN_3(ALU, MOV, K), \
+ INSN_3(ALU, DIV, K), \
+ INSN_3(ALU, MOD, K), \
+ /* 64 bit ALU operations. */ \
+ /* Register based. */ \
+ INSN_3(ALU64, ADD, X), \
+ INSN_3(ALU64, SUB, X), \
+ INSN_3(ALU64, AND, X), \
+ INSN_3(ALU64, OR, X), \
+ INSN_3(ALU64, LSH, X), \
+ INSN_3(ALU64, RSH, X), \
+ INSN_3(ALU64, XOR, X), \
+ INSN_3(ALU64, MUL, X), \
+ INSN_3(ALU64, MOV, X), \
+ INSN_3(ALU64, ARSH, X), \
+ INSN_3(ALU64, DIV, X), \
+ INSN_3(ALU64, MOD, X), \
+ INSN_2(ALU64, NEG), \
+ /* Immediate based. */ \
+ INSN_3(ALU64, ADD, K), \
+ INSN_3(ALU64, SUB, K), \
+ INSN_3(ALU64, AND, K), \
+ INSN_3(ALU64, OR, K), \
+ INSN_3(ALU64, LSH, K), \
+ INSN_3(ALU64, RSH, K), \
+ INSN_3(ALU64, XOR, K), \
+ INSN_3(ALU64, MUL, K), \
+ INSN_3(ALU64, MOV, K), \
+ INSN_3(ALU64, ARSH, K), \
+ INSN_3(ALU64, DIV, K), \
+ INSN_3(ALU64, MOD, K), \
+ /* Call instruction. */ \
+ INSN_2(JMP, CALL), \
+ /* Exit instruction. */ \
+ INSN_2(JMP, EXIT), \
+ /* Jump instructions. */ \
+ /* Register based. */ \
+ INSN_3(JMP, JEQ, X), \
+ INSN_3(JMP, JNE, X), \
+ INSN_3(JMP, JGT, X), \
+ INSN_3(JMP, JLT, X), \
+ INSN_3(JMP, JGE, X), \
+ INSN_3(JMP, JLE, X), \
+ INSN_3(JMP, JSGT, X), \
+ INSN_3(JMP, JSLT, X), \
+ INSN_3(JMP, JSGE, X), \
+ INSN_3(JMP, JSLE, X), \
+ INSN_3(JMP, JSET, X), \
+ /* Immediate based. */ \
+ INSN_3(JMP, JEQ, K), \
+ INSN_3(JMP, JNE, K), \
+ INSN_3(JMP, JGT, K), \
+ INSN_3(JMP, JLT, K), \
+ INSN_3(JMP, JGE, K), \
+ INSN_3(JMP, JLE, K), \
+ INSN_3(JMP, JSGT, K), \
+ INSN_3(JMP, JSLT, K), \
+ INSN_3(JMP, JSGE, K), \
+ INSN_3(JMP, JSLE, K), \
+ INSN_3(JMP, JSET, K), \
+ INSN_2(JMP, JA), \
+ /* Store instructions. */ \
+ /* Register based. */ \
+ INSN_3(STX, MEM, B), \
+ INSN_3(STX, MEM, H), \
+ INSN_3(STX, MEM, W), \
+ INSN_3(STX, MEM, DW), \
+ INSN_3(STX, XADD, W), \
+ INSN_3(STX, XADD, DW), \
+ /* Immediate based. */ \
+ INSN_3(ST, MEM, B), \
+ INSN_3(ST, MEM, H), \
+ INSN_3(ST, MEM, W), \
+ INSN_3(ST, MEM, DW), \
+ /* Load instructions. */ \
+ /* Register based. */ \
+ INSN_3(LDX, MEM, B), \
+ INSN_3(LDX, MEM, H), \
+ INSN_3(LDX, MEM, W), \
+ INSN_3(LDX, MEM, DW), \
+ /* Immediate based. */ \
+ INSN_3(LD, IMM, DW), \
+ /* Misc (old cBPF carry-over). */ \
+ INSN_3(LD, ABS, B), \
+ INSN_3(LD, ABS, H), \
+ INSN_3(LD, ABS, W), \
+ INSN_3(LD, IND, B), \
+ INSN_3(LD, IND, H), \
+ INSN_3(LD, IND, W)
+
+bool bpf_opcode_in_insntable(u8 code)
+{
+#define BPF_INSN_2_TBL(x, y) [BPF_##x | BPF_##y] = true
+#define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true
+ static const bool public_insntable[256] = {
+ [0 ... 255] = false,
+ /* Now overwrite non-defaults ... */
+ BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL),
+ };
+#undef BPF_INSN_3_TBL
+#undef BPF_INSN_2_TBL
+ return public_insntable[code];
+}
+
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
/**
* __bpf_prog_run - run eBPF program on a given context
@@ -775,118 +921,21 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
*
* Decode and execute eBPF instructions.
*/
-static unsigned int ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn,
- u64 *stack)
+static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
{
u64 tmp;
+#define BPF_INSN_2_LBL(x, y) [BPF_##x | BPF_##y] = &&x##_##y
+#define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z
static const void *jumptable[256] = {
[0 ... 255] = &&default_label,
/* Now overwrite non-defaults ... */
- /* 32 bit ALU operations */
- [BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X,
- [BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K,
- [BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X,
- [BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K,
- [BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X,
- [BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K,
- [BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X,
- [BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K,
- [BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X,
- [BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K,
- [BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X,
- [BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K,
- [BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X,
- [BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K,
- [BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X,
- [BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K,
- [BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X,
- [BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K,
- [BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X,
- [BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K,
- [BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X,
- [BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K,
- [BPF_ALU | BPF_NEG] = &&ALU_NEG,
- [BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE,
- [BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE,
- /* 64 bit ALU operations */
- [BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X,
- [BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K,
- [BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X,
- [BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K,
- [BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X,
- [BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K,
- [BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X,
- [BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K,
- [BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X,
- [BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K,
- [BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X,
- [BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K,
- [BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X,
- [BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K,
- [BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X,
- [BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K,
- [BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X,
- [BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K,
- [BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X,
- [BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K,
- [BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X,
- [BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K,
- [BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X,
- [BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K,
- [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG,
- /* Call instruction */
- [BPF_JMP | BPF_CALL] = &&JMP_CALL,
+ BPF_INSN_MAP(BPF_INSN_2_LBL, BPF_INSN_3_LBL),
+ /* Non-UAPI available opcodes. */
+ [BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS,
[BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL,
- /* Jumps */
- [BPF_JMP | BPF_JA] = &&JMP_JA,
- [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X,
- [BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K,
- [BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X,
- [BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K,
- [BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X,
- [BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K,
- [BPF_JMP | BPF_JLT | BPF_X] = &&JMP_JLT_X,
- [BPF_JMP | BPF_JLT | BPF_K] = &&JMP_JLT_K,
- [BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X,
- [BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K,
- [BPF_JMP | BPF_JLE | BPF_X] = &&JMP_JLE_X,
- [BPF_JMP | BPF_JLE | BPF_K] = &&JMP_JLE_K,
- [BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X,
- [BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K,
- [BPF_JMP | BPF_JSLT | BPF_X] = &&JMP_JSLT_X,
- [BPF_JMP | BPF_JSLT | BPF_K] = &&JMP_JSLT_K,
- [BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X,
- [BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K,
- [BPF_JMP | BPF_JSLE | BPF_X] = &&JMP_JSLE_X,
- [BPF_JMP | BPF_JSLE | BPF_K] = &&JMP_JSLE_K,
- [BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X,
- [BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K,
- /* Program return */
- [BPF_JMP | BPF_EXIT] = &&JMP_EXIT,
- /* Store instructions */
- [BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B,
- [BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H,
- [BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W,
- [BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW,
- [BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W,
- [BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW,
- [BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B,
- [BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H,
- [BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W,
- [BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW,
- /* Load instructions */
- [BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B,
- [BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H,
- [BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W,
- [BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW,
- [BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W,
- [BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H,
- [BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B,
- [BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W,
- [BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H,
- [BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B,
- [BPF_LD | BPF_IMM | BPF_DW] = &&LD_IMM_DW,
};
+#undef BPF_INSN_3_LBL
+#undef BPF_INSN_2_LBL
u32 tail_call_cnt = 0;
void *ptr;
int off;
@@ -950,14 +999,10 @@ select_insn:
(*(s64 *) &DST) >>= IMM;
CONT;
ALU64_MOD_X:
- if (unlikely(SRC == 0))
- return 0;
div64_u64_rem(DST, SRC, &tmp);
DST = tmp;
CONT;
ALU_MOD_X:
- if (unlikely((u32)SRC == 0))
- return 0;
tmp = (u32) DST;
DST = do_div(tmp, (u32) SRC);
CONT;
@@ -970,13 +1015,9 @@ select_insn:
DST = do_div(tmp, (u32) IMM);
CONT;
ALU64_DIV_X:
- if (unlikely(SRC == 0))
- return 0;
DST = div64_u64(DST, SRC);
CONT;
ALU_DIV_X:
- if (unlikely((u32)SRC == 0))
- return 0;
tmp = (u32) DST;
do_div(tmp, (u32) SRC);
DST = (u32) tmp;
@@ -1026,6 +1067,13 @@ select_insn:
BPF_R4, BPF_R5);
CONT;
+ JMP_CALL_ARGS:
+ BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2,
+ BPF_R3, BPF_R4,
+ BPF_R5,
+ insn + insn->off + 1);
+ CONT;
+
JMP_TAIL_CALL: {
struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2;
struct bpf_array *array = container_of(map, struct bpf_array, map);
@@ -1280,8 +1328,14 @@ load_byte:
goto load_byte;
default_label:
- /* If we ever reach this, we have a bug somewhere. */
- WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code);
+ /* If we ever reach this, we have a bug somewhere. Die hard here
+ * instead of just returning 0; we could be somewhere in a subprog,
+ * so execution could continue otherwise which we do /not/ want.
+ *
+ * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
+ */
+ pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
+ BUG_ON(1);
return 0;
}
STACK_FRAME_NON_STANDARD(___bpf_prog_run); /* jump table */
@@ -1298,6 +1352,23 @@ static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn
return ___bpf_prog_run(regs, insn, stack); \
}
+#define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size
+#define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \
+static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \
+ const struct bpf_insn *insn) \
+{ \
+ u64 stack[stack_size / sizeof(u64)]; \
+ u64 regs[MAX_BPF_REG]; \
+\
+ FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
+ BPF_R1 = r1; \
+ BPF_R2 = r2; \
+ BPF_R3 = r3; \
+ BPF_R4 = r4; \
+ BPF_R5 = r5; \
+ return ___bpf_prog_run(regs, insn, stack); \
+}
+
#define EVAL1(FN, X) FN(X)
#define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y)
#define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y)
@@ -1309,6 +1380,10 @@ EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192);
EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384);
EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512);
+EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192);
+EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384);
+EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512);
+
#define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size),
static unsigned int (*interpreters[])(const void *ctx,
@@ -1317,11 +1392,33 @@ EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
};
+#undef PROG_NAME_LIST
+#define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size),
+static u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5,
+ const struct bpf_insn *insn) = {
+EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
+EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
+EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
+};
+#undef PROG_NAME_LIST
+
+void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth)
+{
+ stack_depth = max_t(u32, stack_depth, 1);
+ insn->off = (s16) insn->imm;
+ insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] -
+ __bpf_call_base_args;
+ insn->code = BPF_JMP | BPF_CALL_ARGS;
+}
#else
-static unsigned int __bpf_prog_ret0(const void *ctx,
- const struct bpf_insn *insn)
+static unsigned int __bpf_prog_ret0_warn(const void *ctx,
+ const struct bpf_insn *insn)
{
+ /* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON
+ * is not working properly, so warn about it!
+ */
+ WARN_ON_ONCE(1);
return 0;
}
#endif
@@ -1329,6 +1426,9 @@ static unsigned int __bpf_prog_ret0(const void *ctx,
bool bpf_prog_array_compatible(struct bpf_array *array,
const struct bpf_prog *fp)
{
+ if (fp->kprobe_override)
+ return false;
+
if (!array->owner_prog_type) {
/* There's no owner yet where we could check for
* compatibility.
@@ -1378,7 +1478,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1];
#else
- fp->bpf_func = __bpf_prog_ret0;
+ fp->bpf_func = __bpf_prog_ret0_warn;
#endif
/* eBPF JITs can rewrite the program in case constant
@@ -1481,6 +1581,8 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs,
rcu_read_lock();
prog = rcu_dereference(progs)->progs;
for (; *prog; prog++) {
+ if (*prog == &dummy_bpf_prog.prog)
+ continue;
id = (*prog)->aux->id;
if (copy_to_user(prog_ids + i, &id, sizeof(id))) {
rcu_read_unlock();
@@ -1564,14 +1666,41 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
return 0;
}
+int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array,
+ __u32 __user *prog_ids, u32 request_cnt,
+ __u32 __user *prog_cnt)
+{
+ u32 cnt = 0;
+
+ if (array)
+ cnt = bpf_prog_array_length(array);
+
+ if (copy_to_user(prog_cnt, &cnt, sizeof(cnt)))
+ return -EFAULT;
+
+ /* return early if user requested only program count or nothing to copy */
+ if (!request_cnt || !cnt)
+ return 0;
+
+ return bpf_prog_array_copy_to_user(array, prog_ids, request_cnt);
+}
+
static void bpf_prog_free_deferred(struct work_struct *work)
{
struct bpf_prog_aux *aux;
+ int i;
aux = container_of(work, struct bpf_prog_aux, work);
if (bpf_prog_is_dev_bound(aux))
bpf_prog_offload_destroy(aux->prog);
- bpf_jit_free(aux->prog);
+ for (i = 0; i < aux->func_cnt; i++)
+ bpf_jit_free(aux->func[i]);
+ if (aux->func_cnt) {
+ kfree(aux->func);
+ bpf_prog_unlock_free(aux->prog);
+ } else {
+ bpf_jit_free(aux->prog);
+ }
}
/* Free internal BPF program */
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index ce5b669003b2..fbfdada6caee 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -94,13 +94,7 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
if (!cmap)
return ERR_PTR(-ENOMEM);
- /* mandatory map attributes */
- cmap->map.map_type = attr->map_type;
- cmap->map.key_size = attr->key_size;
- cmap->map.value_size = attr->value_size;
- cmap->map.max_entries = attr->max_entries;
- cmap->map.map_flags = attr->map_flags;
- cmap->map.numa_node = bpf_map_attr_numa_node(attr);
+ bpf_map_init_from_attr(&cmap->map, attr);
/* Pre-limit array size based on NR_CPUS, not final CPU check */
if (cmap->map.max_entries > NR_CPUS) {
@@ -143,7 +137,7 @@ free_cmap:
return ERR_PTR(err);
}
-void __cpu_map_queue_destructor(void *ptr)
+static void __cpu_map_queue_destructor(void *ptr)
{
/* The tear-down procedure should have made sure that queue is
* empty. See __cpu_map_entry_replace() and work-queue
@@ -222,8 +216,8 @@ static struct xdp_pkt *convert_to_xdp_pkt(struct xdp_buff *xdp)
return xdp_pkt;
}
-struct sk_buff *cpu_map_build_skb(struct bpf_cpu_map_entry *rcpu,
- struct xdp_pkt *xdp_pkt)
+static struct sk_buff *cpu_map_build_skb(struct bpf_cpu_map_entry *rcpu,
+ struct xdp_pkt *xdp_pkt)
{
unsigned int frame_size;
void *pkt_data_start;
@@ -337,7 +331,8 @@ static int cpu_map_kthread_run(void *data)
return 0;
}
-struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu, int map_id)
+static struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu,
+ int map_id)
{
gfp_t gfp = GFP_ATOMIC|__GFP_NOWARN;
struct bpf_cpu_map_entry *rcpu;
@@ -395,7 +390,7 @@ free_rcu:
return NULL;
}
-void __cpu_map_entry_free(struct rcu_head *rcu)
+static void __cpu_map_entry_free(struct rcu_head *rcu)
{
struct bpf_cpu_map_entry *rcpu;
int cpu;
@@ -438,8 +433,8 @@ void __cpu_map_entry_free(struct rcu_head *rcu)
* cpu_map_kthread_stop, which waits for an RCU graze period before
* stopping kthread, emptying the queue.
*/
-void __cpu_map_entry_replace(struct bpf_cpu_map *cmap,
- u32 key_cpu, struct bpf_cpu_map_entry *rcpu)
+static void __cpu_map_entry_replace(struct bpf_cpu_map *cmap,
+ u32 key_cpu, struct bpf_cpu_map_entry *rcpu)
{
struct bpf_cpu_map_entry *old_rcpu;
@@ -451,7 +446,7 @@ void __cpu_map_entry_replace(struct bpf_cpu_map *cmap,
}
}
-int cpu_map_delete_elem(struct bpf_map *map, void *key)
+static int cpu_map_delete_elem(struct bpf_map *map, void *key)
{
struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
u32 key_cpu = *(u32 *)key;
@@ -464,8 +459,8 @@ int cpu_map_delete_elem(struct bpf_map *map, void *key)
return 0;
}
-int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,
- u64 map_flags)
+static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
{
struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
struct bpf_cpu_map_entry *rcpu;
@@ -502,7 +497,7 @@ int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,
return 0;
}
-void cpu_map_free(struct bpf_map *map)
+static void cpu_map_free(struct bpf_map *map)
{
struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
int cpu;
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index ebdef54bf7df..565f9ece9115 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -93,13 +93,7 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
if (!dtab)
return ERR_PTR(-ENOMEM);
- /* mandatory map attributes */
- dtab->map.map_type = attr->map_type;
- dtab->map.key_size = attr->key_size;
- dtab->map.value_size = attr->value_size;
- dtab->map.max_entries = attr->max_entries;
- dtab->map.map_flags = attr->map_flags;
- dtab->map.numa_node = bpf_map_attr_numa_node(attr);
+ bpf_map_init_from_attr(&dtab->map, attr);
/* make sure page count doesn't overflow */
cost = (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *);
diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c
index e682850c9715..8740406df2cd 100644
--- a/kernel/bpf/disasm.c
+++ b/kernel/bpf/disasm.c
@@ -21,10 +21,39 @@ static const char * const func_id_str[] = {
};
#undef __BPF_FUNC_STR_FN
-const char *func_id_name(int id)
+static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
+ const struct bpf_insn *insn,
+ char *buff, size_t len)
{
BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
+ if (insn->src_reg != BPF_PSEUDO_CALL &&
+ insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
+ func_id_str[insn->imm])
+ return func_id_str[insn->imm];
+
+ if (cbs && cbs->cb_call)
+ return cbs->cb_call(cbs->private_data, insn);
+
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ snprintf(buff, len, "%+d", insn->imm);
+
+ return buff;
+}
+
+static const char *__func_imm_name(const struct bpf_insn_cbs *cbs,
+ const struct bpf_insn *insn,
+ u64 full_imm, char *buff, size_t len)
+{
+ if (cbs && cbs->cb_imm)
+ return cbs->cb_imm(cbs->private_data, insn, full_imm);
+
+ snprintf(buff, len, "0x%llx", (unsigned long long)full_imm);
+ return buff;
+}
+
+const char *func_id_name(int id)
+{
if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
return func_id_str[id];
else
@@ -83,7 +112,7 @@ static const char *const bpf_jmp_string[16] = {
[BPF_EXIT >> 4] = "exit",
};
-static void print_bpf_end_insn(bpf_insn_print_cb verbose,
+static void print_bpf_end_insn(bpf_insn_print_t verbose,
struct bpf_verifier_env *env,
const struct bpf_insn *insn)
{
@@ -92,9 +121,12 @@ static void print_bpf_end_insn(bpf_insn_print_cb verbose,
insn->imm, insn->dst_reg);
}
-void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
- const struct bpf_insn *insn, bool allow_ptr_leaks)
+void print_bpf_insn(const struct bpf_insn_cbs *cbs,
+ struct bpf_verifier_env *env,
+ const struct bpf_insn *insn,
+ bool allow_ptr_leaks)
{
+ const bpf_insn_print_t verbose = cbs->cb_print;
u8 class = BPF_CLASS(insn->code);
if (class == BPF_ALU || class == BPF_ALU64) {
@@ -175,12 +207,15 @@ void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
*/
u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
+ char tmp[64];
if (map_ptr && !allow_ptr_leaks)
imm = 0;
- verbose(env, "(%02x) r%d = 0x%llx\n", insn->code,
- insn->dst_reg, (unsigned long long)imm);
+ verbose(env, "(%02x) r%d = %s\n",
+ insn->code, insn->dst_reg,
+ __func_imm_name(cbs, insn, imm,
+ tmp, sizeof(tmp)));
} else {
verbose(env, "BUG_ld_%02x\n", insn->code);
return;
@@ -189,8 +224,20 @@ void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
u8 opcode = BPF_OP(insn->code);
if (opcode == BPF_CALL) {
- verbose(env, "(%02x) call %s#%d\n", insn->code,
- func_id_name(insn->imm), insn->imm);
+ char tmp[64];
+
+ if (insn->src_reg == BPF_PSEUDO_CALL) {
+ verbose(env, "(%02x) call pc%s\n",
+ insn->code,
+ __func_get_name(cbs, insn,
+ tmp, sizeof(tmp)));
+ } else {
+ strcpy(tmp, "unknown");
+ verbose(env, "(%02x) call %s#%d\n", insn->code,
+ __func_get_name(cbs, insn,
+ tmp, sizeof(tmp)),
+ insn->imm);
+ }
} else if (insn->code == (BPF_JMP | BPF_JA)) {
verbose(env, "(%02x) goto pc%+d\n",
insn->code, insn->off);
diff --git a/kernel/bpf/disasm.h b/kernel/bpf/disasm.h
index 8de977e420b6..266fe8ee542b 100644
--- a/kernel/bpf/disasm.h
+++ b/kernel/bpf/disasm.h
@@ -17,16 +17,35 @@
#include <linux/bpf.h>
#include <linux/kernel.h>
#include <linux/stringify.h>
+#ifndef __KERNEL__
+#include <stdio.h>
+#include <string.h>
+#endif
+
+struct bpf_verifier_env;
extern const char *const bpf_alu_string[16];
extern const char *const bpf_class_string[8];
const char *func_id_name(int id);
-struct bpf_verifier_env;
-typedef void (*bpf_insn_print_cb)(struct bpf_verifier_env *env,
- const char *, ...);
-void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env,
- const struct bpf_insn *insn, bool allow_ptr_leaks);
+typedef __printf(2, 3) void (*bpf_insn_print_t)(struct bpf_verifier_env *env,
+ const char *, ...);
+typedef const char *(*bpf_insn_revmap_call_t)(void *private_data,
+ const struct bpf_insn *insn);
+typedef const char *(*bpf_insn_print_imm_t)(void *private_data,
+ const struct bpf_insn *insn,
+ __u64 full_imm);
+
+struct bpf_insn_cbs {
+ bpf_insn_print_t cb_print;
+ bpf_insn_revmap_call_t cb_call;
+ bpf_insn_print_imm_t cb_imm;
+ void *private_data;
+};
+void print_bpf_insn(const struct bpf_insn_cbs *cbs,
+ struct bpf_verifier_env *env,
+ const struct bpf_insn *insn,
+ bool allow_ptr_leaks);
#endif
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 3905d4bc5b80..b76828f23b49 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -227,7 +227,7 @@ static int alloc_extra_elems(struct bpf_htab *htab)
}
/* Called from syscall */
-static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
+static int htab_map_alloc_check(union bpf_attr *attr)
{
bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
@@ -241,9 +241,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU);
bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
int numa_node = bpf_map_attr_numa_node(attr);
- struct bpf_htab *htab;
- int err, i;
- u64 cost;
BUILD_BUG_ON(offsetof(struct htab_elem, htab) !=
offsetof(struct htab_elem, hash_node.pprev));
@@ -254,40 +251,68 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
/* LRU implementation is much complicated than other
* maps. Hence, limit to CAP_SYS_ADMIN for now.
*/
- return ERR_PTR(-EPERM);
+ return -EPERM;
if (attr->map_flags & ~HTAB_CREATE_FLAG_MASK)
/* reserved bits should not be used */
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
if (!lru && percpu_lru)
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
if (lru && !prealloc)
- return ERR_PTR(-ENOTSUPP);
+ return -ENOTSUPP;
if (numa_node != NUMA_NO_NODE && (percpu || percpu_lru))
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
+
+ /* check sanity of attributes.
+ * value_size == 0 may be allowed in the future to use map as a set
+ */
+ if (attr->max_entries == 0 || attr->key_size == 0 ||
+ attr->value_size == 0)
+ return -EINVAL;
+
+ if (attr->key_size > MAX_BPF_STACK)
+ /* eBPF programs initialize keys on stack, so they cannot be
+ * larger than max stack size
+ */
+ return -E2BIG;
+
+ if (attr->value_size >= KMALLOC_MAX_SIZE -
+ MAX_BPF_STACK - sizeof(struct htab_elem))
+ /* if value_size is bigger, the user space won't be able to
+ * access the elements via bpf syscall. This check also makes
+ * sure that the elem_size doesn't overflow and it's
+ * kmalloc-able later in htab_map_update_elem()
+ */
+ return -E2BIG;
+
+ return 0;
+}
+
+static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
+{
+ bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ bool lru = (attr->map_type == BPF_MAP_TYPE_LRU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ /* percpu_lru means each cpu has its own LRU list.
+ * it is different from BPF_MAP_TYPE_PERCPU_HASH where
+ * the map's value itself is percpu. percpu_lru has
+ * nothing to do with the map's value.
+ */
+ bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU);
+ bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
+ struct bpf_htab *htab;
+ int err, i;
+ u64 cost;
htab = kzalloc(sizeof(*htab), GFP_USER);
if (!htab)
return ERR_PTR(-ENOMEM);
- /* mandatory map attributes */
- htab->map.map_type = attr->map_type;
- htab->map.key_size = attr->key_size;
- htab->map.value_size = attr->value_size;
- htab->map.max_entries = attr->max_entries;
- htab->map.map_flags = attr->map_flags;
- htab->map.numa_node = numa_node;
-
- /* check sanity of attributes.
- * value_size == 0 may be allowed in the future to use map as a set
- */
- err = -EINVAL;
- if (htab->map.max_entries == 0 || htab->map.key_size == 0 ||
- htab->map.value_size == 0)
- goto free_htab;
+ bpf_map_init_from_attr(&htab->map, attr);
if (percpu_lru) {
/* ensure each CPU's lru list has >=1 elements.
@@ -304,22 +329,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
/* hash table size must be power of 2 */
htab->n_buckets = roundup_pow_of_two(htab->map.max_entries);
- err = -E2BIG;
- if (htab->map.key_size > MAX_BPF_STACK)
- /* eBPF programs initialize keys on stack, so they cannot be
- * larger than max stack size
- */
- goto free_htab;
-
- if (htab->map.value_size >= KMALLOC_MAX_SIZE -
- MAX_BPF_STACK - sizeof(struct htab_elem))
- /* if value_size is bigger, the user space won't be able to
- * access the elements via bpf syscall. This check also makes
- * sure that the elem_size doesn't overflow and it's
- * kmalloc-able later in htab_map_update_elem()
- */
- goto free_htab;
-
htab->elem_size = sizeof(struct htab_elem) +
round_up(htab->map.key_size, 8);
if (percpu)
@@ -327,6 +336,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
else
htab->elem_size += round_up(htab->map.value_size, 8);
+ err = -E2BIG;
/* prevent zero size kmalloc and check for u32 overflow */
if (htab->n_buckets == 0 ||
htab->n_buckets > U32_MAX / sizeof(struct bucket))
@@ -1143,6 +1153,7 @@ static void htab_map_free(struct bpf_map *map)
}
const struct bpf_map_ops htab_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1153,6 +1164,7 @@ const struct bpf_map_ops htab_map_ops = {
};
const struct bpf_map_ops htab_lru_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1236,6 +1248,7 @@ int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
}
const struct bpf_map_ops htab_percpu_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1245,6 +1258,7 @@ const struct bpf_map_ops htab_percpu_map_ops = {
};
const struct bpf_map_ops htab_lru_percpu_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
@@ -1253,11 +1267,11 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = {
.map_delete_elem = htab_lru_map_delete_elem,
};
-static struct bpf_map *fd_htab_map_alloc(union bpf_attr *attr)
+static int fd_htab_map_alloc_check(union bpf_attr *attr)
{
if (attr->value_size != sizeof(u32))
- return ERR_PTR(-EINVAL);
- return htab_map_alloc(attr);
+ return -EINVAL;
+ return htab_map_alloc_check(attr);
}
static void fd_htab_map_free(struct bpf_map *map)
@@ -1328,7 +1342,7 @@ static struct bpf_map *htab_of_map_alloc(union bpf_attr *attr)
if (IS_ERR(inner_map_meta))
return inner_map_meta;
- map = fd_htab_map_alloc(attr);
+ map = htab_map_alloc(attr);
if (IS_ERR(map)) {
bpf_map_meta_free(inner_map_meta);
return map;
@@ -1372,6 +1386,7 @@ static void htab_of_map_free(struct bpf_map *map)
}
const struct bpf_map_ops htab_of_maps_map_ops = {
+ .map_alloc_check = fd_htab_map_alloc_check,
.map_alloc = htab_of_map_alloc,
.map_free = htab_of_map_free,
.map_get_next_key = htab_map_get_next_key,
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 885e45479680..7b469d10d0e9 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -522,12 +522,7 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr)
return ERR_PTR(-ENOMEM);
/* copy mandatory map attributes */
- trie->map.map_type = attr->map_type;
- trie->map.key_size = attr->key_size;
- trie->map.value_size = attr->value_size;
- trie->map.max_entries = attr->max_entries;
- trie->map.map_flags = attr->map_flags;
- trie->map.numa_node = bpf_map_attr_numa_node(attr);
+ bpf_map_init_from_attr(&trie->map, attr);
trie->data_size = attr->key_size -
offsetof(struct bpf_lpm_trie_key, data);
trie->max_prefixlen = trie->data_size * 8;
@@ -596,9 +591,96 @@ unlock:
raw_spin_unlock(&trie->lock);
}
-static int trie_get_next_key(struct bpf_map *map, void *key, void *next_key)
+static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
{
- return -ENOTSUPP;
+ struct lpm_trie_node *node, *next_node = NULL, *parent, *search_root;
+ struct lpm_trie *trie = container_of(map, struct lpm_trie, map);
+ struct bpf_lpm_trie_key *key = _key, *next_key = _next_key;
+ struct lpm_trie_node **node_stack = NULL;
+ int err = 0, stack_ptr = -1;
+ unsigned int next_bit;
+ size_t matchlen;
+
+ /* The get_next_key follows postorder. For the 4 node example in
+ * the top of this file, the trie_get_next_key() returns the following
+ * one after another:
+ * 192.168.0.0/24
+ * 192.168.1.0/24
+ * 192.168.128.0/24
+ * 192.168.0.0/16
+ *
+ * The idea is to return more specific keys before less specific ones.
+ */
+
+ /* Empty trie */
+ search_root = rcu_dereference(trie->root);
+ if (!search_root)
+ return -ENOENT;
+
+ /* For invalid key, find the leftmost node in the trie */
+ if (!key || key->prefixlen > trie->max_prefixlen)
+ goto find_leftmost;
+
+ node_stack = kmalloc(trie->max_prefixlen * sizeof(struct lpm_trie_node *),
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (!node_stack)
+ return -ENOMEM;
+
+ /* Try to find the exact node for the given key */
+ for (node = search_root; node;) {
+ node_stack[++stack_ptr] = node;
+ matchlen = longest_prefix_match(trie, node, key);
+ if (node->prefixlen != matchlen ||
+ node->prefixlen == key->prefixlen)
+ break;
+
+ next_bit = extract_bit(key->data, node->prefixlen);
+ node = rcu_dereference(node->child[next_bit]);
+ }
+ if (!node || node->prefixlen != key->prefixlen ||
+ (node->flags & LPM_TREE_NODE_FLAG_IM))
+ goto find_leftmost;
+
+ /* The node with the exactly-matching key has been found,
+ * find the first node in postorder after the matched node.
+ */
+ node = node_stack[stack_ptr];
+ while (stack_ptr > 0) {
+ parent = node_stack[stack_ptr - 1];
+ if (rcu_dereference(parent->child[0]) == node) {
+ search_root = rcu_dereference(parent->child[1]);
+ if (search_root)
+ goto find_leftmost;
+ }
+ if (!(parent->flags & LPM_TREE_NODE_FLAG_IM)) {
+ next_node = parent;
+ goto do_copy;
+ }
+
+ node = parent;
+ stack_ptr--;
+ }
+
+ /* did not find anything */
+ err = -ENOENT;
+ goto free_stack;
+
+find_leftmost:
+ /* Find the leftmost non-intermediate node, all intermediate nodes
+ * have exact two children, so this function will never return NULL.
+ */
+ for (node = search_root; node;) {
+ if (!(node->flags & LPM_TREE_NODE_FLAG_IM))
+ next_node = node;
+ node = rcu_dereference(node->child[0]);
+ }
+do_copy:
+ next_key->prefixlen = next_node->prefixlen;
+ memcpy((void *)next_key + offsetof(struct bpf_lpm_trie_key, data),
+ next_node->data, trie->data_size);
+free_stack:
+ kfree(node_stack);
+ return err;
}
const struct bpf_map_ops trie_map_ops = {
diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
index 8455b89d1bbf..c9401075b58c 100644
--- a/kernel/bpf/offload.c
+++ b/kernel/bpf/offload.c
@@ -16,18 +16,35 @@
#include <linux/bpf.h>
#include <linux/bpf_verifier.h>
#include <linux/bug.h>
+#include <linux/kdev_t.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/printk.h>
+#include <linux/proc_ns.h>
#include <linux/rtnetlink.h>
+#include <linux/rwsem.h>
-/* protected by RTNL */
+/* Protects bpf_prog_offload_devs, bpf_map_offload_devs and offload members
+ * of all progs.
+ * RTNL lock cannot be taken when holding this lock.
+ */
+static DECLARE_RWSEM(bpf_devs_lock);
static LIST_HEAD(bpf_prog_offload_devs);
+static LIST_HEAD(bpf_map_offload_devs);
+
+static int bpf_dev_offload_check(struct net_device *netdev)
+{
+ if (!netdev)
+ return -EINVAL;
+ if (!netdev->netdev_ops->ndo_bpf)
+ return -EOPNOTSUPP;
+ return 0;
+}
int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
{
- struct net *net = current->nsproxy->net_ns;
- struct bpf_dev_offload *offload;
+ struct bpf_prog_offload *offload;
+ int err;
if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS &&
attr->prog_type != BPF_PROG_TYPE_XDP)
@@ -41,34 +58,44 @@ int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
return -ENOMEM;
offload->prog = prog;
- init_waitqueue_head(&offload->verifier_done);
- rtnl_lock();
- offload->netdev = __dev_get_by_index(net, attr->prog_ifindex);
- if (!offload->netdev) {
- rtnl_unlock();
- kfree(offload);
- return -EINVAL;
- }
+ offload->netdev = dev_get_by_index(current->nsproxy->net_ns,
+ attr->prog_ifindex);
+ err = bpf_dev_offload_check(offload->netdev);
+ if (err)
+ goto err_maybe_put;
+ down_write(&bpf_devs_lock);
+ if (offload->netdev->reg_state != NETREG_REGISTERED) {
+ err = -EINVAL;
+ goto err_unlock;
+ }
prog->aux->offload = offload;
list_add_tail(&offload->offloads, &bpf_prog_offload_devs);
- rtnl_unlock();
+ dev_put(offload->netdev);
+ up_write(&bpf_devs_lock);
return 0;
+err_unlock:
+ up_write(&bpf_devs_lock);
+err_maybe_put:
+ if (offload->netdev)
+ dev_put(offload->netdev);
+ kfree(offload);
+ return err;
}
static int __bpf_offload_ndo(struct bpf_prog *prog, enum bpf_netdev_command cmd,
struct netdev_bpf *data)
{
- struct net_device *netdev = prog->aux->offload->netdev;
+ struct bpf_prog_offload *offload = prog->aux->offload;
+ struct net_device *netdev;
ASSERT_RTNL();
- if (!netdev)
+ if (!offload)
return -ENODEV;
- if (!netdev->netdev_ops->ndo_bpf)
- return -EOPNOTSUPP;
+ netdev = offload->netdev;
data->command = cmd;
@@ -87,62 +114,63 @@ int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env)
if (err)
goto exit_unlock;
- env->dev_ops = data.verifier.ops;
-
+ env->prog->aux->offload->dev_ops = data.verifier.ops;
env->prog->aux->offload->dev_state = true;
- env->prog->aux->offload->verifier_running = true;
exit_unlock:
rtnl_unlock();
return err;
}
+int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
+ int insn_idx, int prev_insn_idx)
+{
+ struct bpf_prog_offload *offload;
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ offload = env->prog->aux->offload;
+ if (offload)
+ ret = offload->dev_ops->insn_hook(env, insn_idx, prev_insn_idx);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
static void __bpf_prog_offload_destroy(struct bpf_prog *prog)
{
- struct bpf_dev_offload *offload = prog->aux->offload;
+ struct bpf_prog_offload *offload = prog->aux->offload;
struct netdev_bpf data = {};
- /* Caution - if netdev is destroyed before the program, this function
- * will be called twice.
- */
-
data.offload.prog = prog;
- if (offload->verifier_running)
- wait_event(offload->verifier_done, !offload->verifier_running);
-
if (offload->dev_state)
WARN_ON(__bpf_offload_ndo(prog, BPF_OFFLOAD_DESTROY, &data));
- offload->dev_state = false;
+ /* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */
+ bpf_prog_free_id(prog, true);
+
list_del_init(&offload->offloads);
- offload->netdev = NULL;
+ kfree(offload);
+ prog->aux->offload = NULL;
}
void bpf_prog_offload_destroy(struct bpf_prog *prog)
{
- struct bpf_dev_offload *offload = prog->aux->offload;
-
- offload->verifier_running = false;
- wake_up(&offload->verifier_done);
-
rtnl_lock();
- __bpf_prog_offload_destroy(prog);
+ down_write(&bpf_devs_lock);
+ if (prog->aux->offload)
+ __bpf_prog_offload_destroy(prog);
+ up_write(&bpf_devs_lock);
rtnl_unlock();
-
- kfree(offload);
}
static int bpf_prog_offload_translate(struct bpf_prog *prog)
{
- struct bpf_dev_offload *offload = prog->aux->offload;
struct netdev_bpf data = {};
int ret;
data.offload.prog = prog;
- offload->verifier_running = false;
- wake_up(&offload->verifier_done);
-
rtnl_lock();
ret = __bpf_offload_ndo(prog, BPF_OFFLOAD_TRANSLATE, &data);
rtnl_unlock();
@@ -164,14 +192,323 @@ int bpf_prog_offload_compile(struct bpf_prog *prog)
return bpf_prog_offload_translate(prog);
}
+struct ns_get_path_bpf_prog_args {
+ struct bpf_prog *prog;
+ struct bpf_prog_info *info;
+};
+
+static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data)
+{
+ struct ns_get_path_bpf_prog_args *args = private_data;
+ struct bpf_prog_aux *aux = args->prog->aux;
+ struct ns_common *ns;
+ struct net *net;
+
+ rtnl_lock();
+ down_read(&bpf_devs_lock);
+
+ if (aux->offload) {
+ args->info->ifindex = aux->offload->netdev->ifindex;
+ net = dev_net(aux->offload->netdev);
+ get_net(net);
+ ns = &net->ns;
+ } else {
+ args->info->ifindex = 0;
+ ns = NULL;
+ }
+
+ up_read(&bpf_devs_lock);
+ rtnl_unlock();
+
+ return ns;
+}
+
+int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
+ struct bpf_prog *prog)
+{
+ struct ns_get_path_bpf_prog_args args = {
+ .prog = prog,
+ .info = info,
+ };
+ struct bpf_prog_aux *aux = prog->aux;
+ struct inode *ns_inode;
+ struct path ns_path;
+ char __user *uinsns;
+ void *res;
+ u32 ulen;
+
+ res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args);
+ if (IS_ERR(res)) {
+ if (!info->ifindex)
+ return -ENODEV;
+ return PTR_ERR(res);
+ }
+
+ down_read(&bpf_devs_lock);
+
+ if (!aux->offload) {
+ up_read(&bpf_devs_lock);
+ return -ENODEV;
+ }
+
+ ulen = info->jited_prog_len;
+ info->jited_prog_len = aux->offload->jited_len;
+ if (info->jited_prog_len & ulen) {
+ uinsns = u64_to_user_ptr(info->jited_prog_insns);
+ ulen = min_t(u32, info->jited_prog_len, ulen);
+ if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) {
+ up_read(&bpf_devs_lock);
+ return -EFAULT;
+ }
+ }
+
+ up_read(&bpf_devs_lock);
+
+ ns_inode = ns_path.dentry->d_inode;
+ info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
+ info->netns_ino = ns_inode->i_ino;
+ path_put(&ns_path);
+
+ return 0;
+}
+
const struct bpf_prog_ops bpf_offload_prog_ops = {
};
+static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap,
+ enum bpf_netdev_command cmd)
+{
+ struct netdev_bpf data = {};
+ struct net_device *netdev;
+
+ ASSERT_RTNL();
+
+ data.command = cmd;
+ data.offmap = offmap;
+ /* Caller must make sure netdev is valid */
+ netdev = offmap->netdev;
+
+ return netdev->netdev_ops->ndo_bpf(netdev, &data);
+}
+
+struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct bpf_offloaded_map *offmap;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return ERR_PTR(-EPERM);
+ if (attr->map_type != BPF_MAP_TYPE_ARRAY &&
+ attr->map_type != BPF_MAP_TYPE_HASH)
+ return ERR_PTR(-EINVAL);
+
+ offmap = kzalloc(sizeof(*offmap), GFP_USER);
+ if (!offmap)
+ return ERR_PTR(-ENOMEM);
+
+ bpf_map_init_from_attr(&offmap->map, attr);
+
+ rtnl_lock();
+ down_write(&bpf_devs_lock);
+ offmap->netdev = __dev_get_by_index(net, attr->map_ifindex);
+ err = bpf_dev_offload_check(offmap->netdev);
+ if (err)
+ goto err_unlock;
+
+ err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC);
+ if (err)
+ goto err_unlock;
+
+ list_add_tail(&offmap->offloads, &bpf_map_offload_devs);
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+
+ return &offmap->map;
+
+err_unlock:
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+ kfree(offmap);
+ return ERR_PTR(err);
+}
+
+static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap)
+{
+ WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE));
+ /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */
+ bpf_map_free_id(&offmap->map, true);
+ list_del_init(&offmap->offloads);
+ offmap->netdev = NULL;
+}
+
+void bpf_map_offload_map_free(struct bpf_map *map)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+
+ rtnl_lock();
+ down_write(&bpf_devs_lock);
+ if (offmap->netdev)
+ __bpf_map_offload_destroy(offmap);
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+
+ kfree(offmap);
+}
+
+int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_lookup_elem(offmap, key, value);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_update_elem(struct bpf_map *map,
+ void *key, void *value, u64 flags)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ if (unlikely(flags > BPF_EXIST))
+ return -EINVAL;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_update_elem(offmap, key, value,
+ flags);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_delete_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_delete_elem(offmap, key);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+struct ns_get_path_bpf_map_args {
+ struct bpf_offloaded_map *offmap;
+ struct bpf_map_info *info;
+};
+
+static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data)
+{
+ struct ns_get_path_bpf_map_args *args = private_data;
+ struct ns_common *ns;
+ struct net *net;
+
+ rtnl_lock();
+ down_read(&bpf_devs_lock);
+
+ if (args->offmap->netdev) {
+ args->info->ifindex = args->offmap->netdev->ifindex;
+ net = dev_net(args->offmap->netdev);
+ get_net(net);
+ ns = &net->ns;
+ } else {
+ args->info->ifindex = 0;
+ ns = NULL;
+ }
+
+ up_read(&bpf_devs_lock);
+ rtnl_unlock();
+
+ return ns;
+}
+
+int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map)
+{
+ struct ns_get_path_bpf_map_args args = {
+ .offmap = map_to_offmap(map),
+ .info = info,
+ };
+ struct inode *ns_inode;
+ struct path ns_path;
+ void *res;
+
+ res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args);
+ if (IS_ERR(res)) {
+ if (!info->ifindex)
+ return -ENODEV;
+ return PTR_ERR(res);
+ }
+
+ ns_inode = ns_path.dentry->d_inode;
+ info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
+ info->netns_ino = ns_inode->i_ino;
+ path_put(&ns_path);
+
+ return 0;
+}
+
+bool bpf_offload_dev_match(struct bpf_prog *prog, struct bpf_map *map)
+{
+ struct bpf_offloaded_map *offmap;
+ struct bpf_prog_offload *offload;
+ bool ret;
+
+ if (!bpf_prog_is_dev_bound(prog->aux) || !bpf_map_is_dev_bound(map))
+ return false;
+
+ down_read(&bpf_devs_lock);
+ offload = prog->aux->offload;
+ offmap = map_to_offmap(map);
+
+ ret = offload && offload->netdev == offmap->netdev;
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+static void bpf_offload_orphan_all_progs(struct net_device *netdev)
+{
+ struct bpf_prog_offload *offload, *tmp;
+
+ list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs, offloads)
+ if (offload->netdev == netdev)
+ __bpf_prog_offload_destroy(offload->prog);
+}
+
+static void bpf_offload_orphan_all_maps(struct net_device *netdev)
+{
+ struct bpf_offloaded_map *offmap, *tmp;
+
+ list_for_each_entry_safe(offmap, tmp, &bpf_map_offload_devs, offloads)
+ if (offmap->netdev == netdev)
+ __bpf_map_offload_destroy(offmap);
+}
+
static int bpf_offload_notification(struct notifier_block *notifier,
ulong event, void *ptr)
{
struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
- struct bpf_dev_offload *offload, *tmp;
ASSERT_RTNL();
@@ -181,11 +518,10 @@ static int bpf_offload_notification(struct notifier_block *notifier,
if (netdev->reg_state != NETREG_UNREGISTERING)
break;
- list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs,
- offloads) {
- if (offload->netdev == netdev)
- __bpf_prog_offload_destroy(offload->prog);
- }
+ down_write(&bpf_devs_lock);
+ bpf_offload_orphan_all_progs(netdev);
+ bpf_offload_orphan_all_maps(netdev);
+ up_write(&bpf_devs_lock);
break;
default:
break;
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c
index 1712d319c2d8..0314d1783d77 100644
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -96,14 +96,6 @@ static inline struct smap_psock *smap_psock_sk(const struct sock *sk)
return rcu_dereference_sk_user_data(sk);
}
-/* compute the linear packet data range [data, data_end) for skb when
- * sk_skb type programs are in use.
- */
-static inline void bpf_compute_data_end_sk_skb(struct sk_buff *skb)
-{
- TCP_SKB_CB(skb)->bpf.data_end = skb->data + skb_headlen(skb);
-}
-
enum __sk_action {
__SK_DROP = 0,
__SK_PASS,
@@ -521,13 +513,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
if (!stab)
return ERR_PTR(-ENOMEM);
- /* mandatory map attributes */
- stab->map.map_type = attr->map_type;
- stab->map.key_size = attr->key_size;
- stab->map.value_size = attr->value_size;
- stab->map.max_entries = attr->max_entries;
- stab->map.map_flags = attr->map_flags;
- stab->map.numa_node = bpf_map_attr_numa_node(attr);
+ bpf_map_init_from_attr(&stab->map, attr);
/* make sure page count doesn't overflow */
cost = (u64) stab->map.max_entries * sizeof(struct sock *);
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index a15bc636cc98..b0ecf43f5894 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -88,14 +88,10 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
if (cost >= U32_MAX - PAGE_SIZE)
goto free_smap;
- smap->map.map_type = attr->map_type;
- smap->map.key_size = attr->key_size;
+ bpf_map_init_from_attr(&smap->map, attr);
smap->map.value_size = value_size;
- smap->map.max_entries = attr->max_entries;
- smap->map.map_flags = attr->map_flags;
smap->n_buckets = n_buckets;
smap->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
- smap->map.numa_node = bpf_map_attr_numa_node(attr);
err = bpf_map_precharge_memlock(smap->map.pages);
if (err)
@@ -226,9 +222,33 @@ int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
return 0;
}
-static int stack_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+static int stack_map_get_next_key(struct bpf_map *map, void *key,
+ void *next_key)
{
- return -EINVAL;
+ struct bpf_stack_map *smap = container_of(map,
+ struct bpf_stack_map, map);
+ u32 id;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ if (!key) {
+ id = 0;
+ } else {
+ id = *(u32 *)key;
+ if (id >= smap->n_buckets || !smap->buckets[id])
+ id = 0;
+ else
+ id++;
+ }
+
+ while (id < smap->n_buckets && !smap->buckets[id])
+ id++;
+
+ if (id >= smap->n_buckets)
+ return -ENOENT;
+
+ *(u32 *)next_key = id;
+ return 0;
}
static int stack_map_update_elem(struct bpf_map *map, void *key, void *value,
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5cb783fc8224..e24aa3241387 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -94,18 +94,34 @@ static int check_uarg_tail_zero(void __user *uaddr,
return 0;
}
+const struct bpf_map_ops bpf_map_offload_ops = {
+ .map_alloc = bpf_map_offload_map_alloc,
+ .map_free = bpf_map_offload_map_free,
+};
+
static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
{
+ const struct bpf_map_ops *ops;
struct bpf_map *map;
+ int err;
- if (attr->map_type >= ARRAY_SIZE(bpf_map_types) ||
- !bpf_map_types[attr->map_type])
+ if (attr->map_type >= ARRAY_SIZE(bpf_map_types))
+ return ERR_PTR(-EINVAL);
+ ops = bpf_map_types[attr->map_type];
+ if (!ops)
return ERR_PTR(-EINVAL);
- map = bpf_map_types[attr->map_type]->map_alloc(attr);
+ if (ops->map_alloc_check) {
+ err = ops->map_alloc_check(attr);
+ if (err)
+ return ERR_PTR(err);
+ }
+ if (attr->map_ifindex)
+ ops = &bpf_map_offload_ops;
+ map = ops->map_alloc(attr);
if (IS_ERR(map))
return map;
- map->ops = bpf_map_types[attr->map_type];
+ map->ops = ops;
map->map_type = attr->map_type;
return map;
}
@@ -134,6 +150,16 @@ void bpf_map_area_free(void *area)
kvfree(area);
}
+void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
+{
+ map->map_type = attr->map_type;
+ map->key_size = attr->key_size;
+ map->value_size = attr->value_size;
+ map->max_entries = attr->max_entries;
+ map->map_flags = attr->map_flags;
+ map->numa_node = bpf_map_attr_numa_node(attr);
+}
+
int bpf_map_precharge_memlock(u32 pages)
{
struct user_struct *user = get_current_user();
@@ -189,16 +215,25 @@ static int bpf_map_alloc_id(struct bpf_map *map)
return id > 0 ? 0 : id;
}
-static void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
+void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
{
unsigned long flags;
+ /* Offloaded maps are removed from the IDR store when their device
+ * disappears - even if someone holds an fd to them they are unusable,
+ * the memory is gone, all ops will fail; they are simply waiting for
+ * refcnt to drop to be freed.
+ */
+ if (!map->id)
+ return;
+
if (do_idr_lock)
spin_lock_irqsave(&map_idr_lock, flags);
else
__acquire(&map_idr_lock);
idr_remove(&map_idr, map->id);
+ map->id = 0;
if (do_idr_lock)
spin_unlock_irqrestore(&map_idr_lock, flags);
@@ -378,7 +413,7 @@ static int bpf_obj_name_cpy(char *dst, const char *src)
return 0;
}
-#define BPF_MAP_CREATE_LAST_FIELD map_name
+#define BPF_MAP_CREATE_LAST_FIELD map_ifindex
/* called via syscall */
static int map_create(union bpf_attr *attr)
{
@@ -566,8 +601,10 @@ static int map_lookup_elem(union bpf_attr *attr)
if (!value)
goto free_key;
- if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
- map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_lookup_elem(map, key, value);
+ } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
err = bpf_percpu_hash_copy(map, key, value);
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
err = bpf_percpu_array_copy(map, key, value);
@@ -654,7 +691,10 @@ static int map_update_elem(union bpf_attr *attr)
goto free_value;
/* Need to create a kthread, thus must support schedule */
- if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_update_elem(map, key, value, attr->flags);
+ goto out;
+ } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
err = map->ops->map_update_elem(map, key, value, attr->flags);
goto out;
}
@@ -669,10 +709,7 @@ static int map_update_elem(union bpf_attr *attr)
err = bpf_percpu_hash_update(map, key, value, attr->flags);
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
err = bpf_percpu_array_update(map, key, value, attr->flags);
- } else if (map->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY ||
- map->map_type == BPF_MAP_TYPE_PROG_ARRAY ||
- map->map_type == BPF_MAP_TYPE_CGROUP_ARRAY ||
- map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) {
+ } else if (IS_FD_ARRAY(map)) {
rcu_read_lock();
err = bpf_fd_array_map_update_elem(map, f.file, key, value,
attr->flags);
@@ -731,6 +768,11 @@ static int map_delete_elem(union bpf_attr *attr)
goto err_put;
}
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_delete_elem(map, key);
+ goto out;
+ }
+
preempt_disable();
__this_cpu_inc(bpf_prog_active);
rcu_read_lock();
@@ -738,7 +780,7 @@ static int map_delete_elem(union bpf_attr *attr)
rcu_read_unlock();
__this_cpu_dec(bpf_prog_active);
preempt_enable();
-
+out:
if (!err)
trace_bpf_map_delete_elem(map, ufd, key);
kfree(key);
@@ -788,9 +830,15 @@ static int map_get_next_key(union bpf_attr *attr)
if (!next_key)
goto free_key;
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_get_next_key(map, key, next_key);
+ goto out;
+ }
+
rcu_read_lock();
err = map->ops->map_get_next_key(map, key, next_key);
rcu_read_unlock();
+out:
if (err)
goto free_next_key;
@@ -905,9 +953,13 @@ static int bpf_prog_alloc_id(struct bpf_prog *prog)
return id > 0 ? 0 : id;
}
-static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
+void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
{
- /* cBPF to eBPF migrations are currently not in the idr store. */
+ /* cBPF to eBPF migrations are currently not in the idr store.
+ * Offloaded programs are removed from the store when their device
+ * disappears - even if someone grabs an fd to them they are unusable,
+ * simply waiting for refcnt to drop to be freed.
+ */
if (!prog->aux->id)
return;
@@ -917,6 +969,7 @@ static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
__acquire(&prog_idr_lock);
idr_remove(&prog_idr, prog->aux->id);
+ prog->aux->id = 0;
if (do_idr_lock)
spin_unlock_bh(&prog_idr_lock);
@@ -937,10 +990,16 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
{
if (atomic_dec_and_test(&prog->aux->refcnt)) {
+ int i;
+
trace_bpf_prog_put_rcu(prog);
/* bpf_prog_free_id() must be called first */
bpf_prog_free_id(prog, do_idr_lock);
+
+ for (i = 0; i < prog->aux->func_cnt; i++)
+ bpf_prog_kallsyms_del(prog->aux->func[i]);
bpf_prog_kallsyms_del(prog);
+
call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
}
}
@@ -1151,6 +1210,8 @@ static int bpf_prog_load(union bpf_attr *attr)
if (!prog)
return -ENOMEM;
+ prog->aux->offload_requested = !!attr->prog_ifindex;
+
err = security_bpf_prog_alloc(prog->aux);
if (err)
goto free_prog_nouncharge;
@@ -1172,7 +1233,7 @@ static int bpf_prog_load(union bpf_attr *attr)
atomic_set(&prog->aux->refcnt, 1);
prog->gpl_compatible = is_gpl ? 1 : 0;
- if (attr->prog_ifindex) {
+ if (bpf_prog_is_dev_bound(prog->aux)) {
err = bpf_prog_offload_init(prog, attr);
if (err)
goto free_prog;
@@ -1194,7 +1255,8 @@ static int bpf_prog_load(union bpf_attr *attr)
goto free_used_maps;
/* eBPF program is ready to be JITed */
- prog = bpf_prog_select_runtime(prog, &err);
+ if (!prog->bpf_func)
+ prog = bpf_prog_select_runtime(prog, &err);
if (err < 0)
goto free_used_maps;
@@ -1439,6 +1501,8 @@ static int bpf_prog_test_run(const union bpf_attr *attr,
struct bpf_prog *prog;
int ret = -ENOTSUPP;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
if (CHECK_ATTR(BPF_PROG_TEST_RUN))
return -EINVAL;
@@ -1551,6 +1615,67 @@ static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
return fd;
}
+static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
+ unsigned long addr)
+{
+ int i;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++)
+ if (prog->aux->used_maps[i] == (void *)addr)
+ return prog->aux->used_maps[i];
+ return NULL;
+}
+
+static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
+{
+ const struct bpf_map *map;
+ struct bpf_insn *insns;
+ u64 imm;
+ int i;
+
+ insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
+ GFP_USER);
+ if (!insns)
+ return insns;
+
+ for (i = 0; i < prog->len; i++) {
+ if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
+ insns[i].code = BPF_JMP | BPF_CALL;
+ insns[i].imm = BPF_FUNC_tail_call;
+ /* fall-through */
+ }
+ if (insns[i].code == (BPF_JMP | BPF_CALL) ||
+ insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
+ if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
+ insns[i].code = BPF_JMP | BPF_CALL;
+ if (!bpf_dump_raw_ok())
+ insns[i].imm = 0;
+ continue;
+ }
+
+ if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
+ continue;
+
+ imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
+ map = bpf_map_from_imm(prog, imm);
+ if (map) {
+ insns[i].src_reg = BPF_PSEUDO_MAP_FD;
+ insns[i].imm = map->id;
+ insns[i + 1].imm = 0;
+ continue;
+ }
+
+ if (!bpf_dump_raw_ok() &&
+ imm == (unsigned long)prog->aux) {
+ insns[i].imm = 0;
+ insns[i + 1].imm = 0;
+ continue;
+ }
+ }
+
+ return insns;
+}
+
static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
const union bpf_attr *attr,
union bpf_attr __user *uattr)
@@ -1598,24 +1723,51 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
goto done;
}
- ulen = info.jited_prog_len;
- info.jited_prog_len = prog->jited_len;
- if (info.jited_prog_len && ulen) {
- uinsns = u64_to_user_ptr(info.jited_prog_insns);
- ulen = min_t(u32, info.jited_prog_len, ulen);
- if (copy_to_user(uinsns, prog->bpf_func, ulen))
- return -EFAULT;
- }
-
ulen = info.xlated_prog_len;
info.xlated_prog_len = bpf_prog_insn_size(prog);
if (info.xlated_prog_len && ulen) {
+ struct bpf_insn *insns_sanitized;
+ bool fault;
+
+ if (prog->blinded && !bpf_dump_raw_ok()) {
+ info.xlated_prog_insns = 0;
+ goto done;
+ }
+ insns_sanitized = bpf_insn_prepare_dump(prog);
+ if (!insns_sanitized)
+ return -ENOMEM;
uinsns = u64_to_user_ptr(info.xlated_prog_insns);
ulen = min_t(u32, info.xlated_prog_len, ulen);
- if (copy_to_user(uinsns, prog->insnsi, ulen))
+ fault = copy_to_user(uinsns, insns_sanitized, ulen);
+ kfree(insns_sanitized);
+ if (fault)
return -EFAULT;
}
+ if (bpf_prog_is_dev_bound(prog->aux)) {
+ err = bpf_prog_offload_info_fill(&info, prog);
+ if (err)
+ return err;
+ goto done;
+ }
+
+ /* NOTE: the following code is supposed to be skipped for offload.
+ * bpf_prog_offload_info_fill() is the place to fill similar fields
+ * for offload.
+ */
+ ulen = info.jited_prog_len;
+ info.jited_prog_len = prog->jited_len;
+ if (info.jited_prog_len && ulen) {
+ if (bpf_dump_raw_ok()) {
+ uinsns = u64_to_user_ptr(info.jited_prog_insns);
+ ulen = min_t(u32, info.jited_prog_len, ulen);
+ if (copy_to_user(uinsns, prog->bpf_func, ulen))
+ return -EFAULT;
+ } else {
+ info.jited_prog_insns = 0;
+ }
+ }
+
done:
if (copy_to_user(uinfo, &info, info_len) ||
put_user(info_len, &uattr->info.info_len))
@@ -1646,6 +1798,12 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map,
info.map_flags = map->map_flags;
memcpy(info.name, map->name, sizeof(map->name));
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_info_fill(&info, map);
+ if (err)
+ return err;
+ }
+
if (copy_to_user(uinfo, &info, info_len) ||
put_user(info_len, &uattr->info.info_len))
return -EFAULT;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 13551e623501..5fb69a85d967 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -20,6 +20,8 @@
#include <linux/file.h>
#include <linux/vmalloc.h>
#include <linux/stringify.h>
+#include <linux/bsearch.h>
+#include <linux/sort.h>
#include "disasm.h"
@@ -167,11 +169,11 @@ struct bpf_call_arg_meta {
static DEFINE_MUTEX(bpf_verifier_lock);
/* log_level controls verbosity level of eBPF verifier.
- * verbose() is used to dump the verification trace to the log, so the user
- * can figure out what's wrong with the program
+ * bpf_verifier_log_write() is used to dump the verification trace to the log,
+ * so the user can figure out what's wrong with the program
*/
-static __printf(2, 3) void verbose(struct bpf_verifier_env *env,
- const char *fmt, ...)
+__printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
+ const char *fmt, ...)
{
struct bpf_verifer_log *log = &env->log;
unsigned int n;
@@ -195,6 +197,14 @@ static __printf(2, 3) void verbose(struct bpf_verifier_env *env,
else
log->ubuf = NULL;
}
+EXPORT_SYMBOL_GPL(bpf_verifier_log_write);
+/* Historically bpf_verifier_log_write was called verbose, but the name was too
+ * generic for symbol export. The function was renamed, but not the calls in
+ * the verifier to avoid complicating backports. Hence the alias below.
+ */
+static __printf(2, 3) void verbose(struct bpf_verifier_env *env,
+ const char *fmt, ...)
+ __attribute__((alias("bpf_verifier_log_write")));
static bool type_is_pkt_pointer(enum bpf_reg_type type)
{
@@ -216,23 +226,48 @@ static const char * const reg_type_str[] = {
[PTR_TO_PACKET_END] = "pkt_end",
};
+static void print_liveness(struct bpf_verifier_env *env,
+ enum bpf_reg_liveness live)
+{
+ if (live & (REG_LIVE_READ | REG_LIVE_WRITTEN))
+ verbose(env, "_");
+ if (live & REG_LIVE_READ)
+ verbose(env, "r");
+ if (live & REG_LIVE_WRITTEN)
+ verbose(env, "w");
+}
+
+static struct bpf_func_state *func(struct bpf_verifier_env *env,
+ const struct bpf_reg_state *reg)
+{
+ struct bpf_verifier_state *cur = env->cur_state;
+
+ return cur->frame[reg->frameno];
+}
+
static void print_verifier_state(struct bpf_verifier_env *env,
- struct bpf_verifier_state *state)
+ const struct bpf_func_state *state)
{
- struct bpf_reg_state *reg;
+ const struct bpf_reg_state *reg;
enum bpf_reg_type t;
int i;
+ if (state->frameno)
+ verbose(env, " frame%d:", state->frameno);
for (i = 0; i < MAX_BPF_REG; i++) {
reg = &state->regs[i];
t = reg->type;
if (t == NOT_INIT)
continue;
- verbose(env, " R%d=%s", i, reg_type_str[t]);
+ verbose(env, " R%d", i);
+ print_liveness(env, reg->live);
+ verbose(env, "=%s", reg_type_str[t]);
if ((t == SCALAR_VALUE || t == PTR_TO_STACK) &&
tnum_is_const(reg->var_off)) {
/* reg->off should be 0 for SCALAR_VALUE */
verbose(env, "%lld", reg->var_off.value + reg->off);
+ if (t == PTR_TO_STACK)
+ verbose(env, ",call_%d", func(env, reg)->callsite);
} else {
verbose(env, "(id=%d", reg->id);
if (t != SCALAR_VALUE)
@@ -277,16 +312,21 @@ static void print_verifier_state(struct bpf_verifier_env *env,
}
}
for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] == STACK_SPILL)
- verbose(env, " fp%d=%s",
- -MAX_BPF_STACK + i * BPF_REG_SIZE,
+ if (state->stack[i].slot_type[0] == STACK_SPILL) {
+ verbose(env, " fp%d",
+ (-i - 1) * BPF_REG_SIZE);
+ print_liveness(env, state->stack[i].spilled_ptr.live);
+ verbose(env, "=%s",
reg_type_str[state->stack[i].spilled_ptr.type]);
+ }
+ if (state->stack[i].slot_type[0] == STACK_ZERO)
+ verbose(env, " fp%d=0", (-i - 1) * BPF_REG_SIZE);
}
verbose(env, "\n");
}
-static int copy_stack_state(struct bpf_verifier_state *dst,
- const struct bpf_verifier_state *src)
+static int copy_stack_state(struct bpf_func_state *dst,
+ const struct bpf_func_state *src)
{
if (!src->stack)
return 0;
@@ -302,13 +342,13 @@ static int copy_stack_state(struct bpf_verifier_state *dst,
/* do_check() starts with zero-sized stack in struct bpf_verifier_state to
* make it consume minimal amount of memory. check_stack_write() access from
- * the program calls into realloc_verifier_state() to grow the stack size.
+ * the program calls into realloc_func_state() to grow the stack size.
* Note there is a non-zero 'parent' pointer inside bpf_verifier_state
* which this function copies over. It points to previous bpf_verifier_state
* which is never reallocated
*/
-static int realloc_verifier_state(struct bpf_verifier_state *state, int size,
- bool copy_old)
+static int realloc_func_state(struct bpf_func_state *state, int size,
+ bool copy_old)
{
u32 old_size = state->allocated_stack;
struct bpf_stack_state *new_stack;
@@ -341,10 +381,23 @@ static int realloc_verifier_state(struct bpf_verifier_state *state, int size,
return 0;
}
+static void free_func_state(struct bpf_func_state *state)
+{
+ if (!state)
+ return;
+ kfree(state->stack);
+ kfree(state);
+}
+
static void free_verifier_state(struct bpf_verifier_state *state,
bool free_self)
{
- kfree(state->stack);
+ int i;
+
+ for (i = 0; i <= state->curframe; i++) {
+ free_func_state(state->frame[i]);
+ state->frame[i] = NULL;
+ }
if (free_self)
kfree(state);
}
@@ -352,18 +405,46 @@ static void free_verifier_state(struct bpf_verifier_state *state,
/* copy verifier state from src to dst growing dst stack space
* when necessary to accommodate larger src stack
*/
-static int copy_verifier_state(struct bpf_verifier_state *dst,
- const struct bpf_verifier_state *src)
+static int copy_func_state(struct bpf_func_state *dst,
+ const struct bpf_func_state *src)
{
int err;
- err = realloc_verifier_state(dst, src->allocated_stack, false);
+ err = realloc_func_state(dst, src->allocated_stack, false);
if (err)
return err;
- memcpy(dst, src, offsetof(struct bpf_verifier_state, allocated_stack));
+ memcpy(dst, src, offsetof(struct bpf_func_state, allocated_stack));
return copy_stack_state(dst, src);
}
+static int copy_verifier_state(struct bpf_verifier_state *dst_state,
+ const struct bpf_verifier_state *src)
+{
+ struct bpf_func_state *dst;
+ int i, err;
+
+ /* if dst has more stack frames then src frame, free them */
+ for (i = src->curframe + 1; i <= dst_state->curframe; i++) {
+ free_func_state(dst_state->frame[i]);
+ dst_state->frame[i] = NULL;
+ }
+ dst_state->curframe = src->curframe;
+ dst_state->parent = src->parent;
+ for (i = 0; i <= src->curframe; i++) {
+ dst = dst_state->frame[i];
+ if (!dst) {
+ dst = kzalloc(sizeof(*dst), GFP_KERNEL);
+ if (!dst)
+ return -ENOMEM;
+ dst_state->frame[i] = dst;
+ }
+ err = copy_func_state(dst, src->frame[i]);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
static int pop_stack(struct bpf_verifier_env *env, int *prev_insn_idx,
int *insn_idx)
{
@@ -416,6 +497,8 @@ static struct bpf_verifier_state *push_stack(struct bpf_verifier_env *env,
}
return &elem->st;
err:
+ free_verifier_state(env->cur_state, true);
+ env->cur_state = NULL;
/* pop all elements and return */
while (!pop_stack(env, NULL, NULL));
return NULL;
@@ -425,6 +508,10 @@ err:
static const int caller_saved[CALLER_SAVED_REGS] = {
BPF_REG_0, BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4, BPF_REG_5
};
+#define CALLEE_SAVED_REGS 5
+static const int callee_saved[CALLEE_SAVED_REGS] = {
+ BPF_REG_6, BPF_REG_7, BPF_REG_8, BPF_REG_9
+};
static void __mark_reg_not_init(struct bpf_reg_state *reg);
@@ -449,6 +536,13 @@ static void __mark_reg_known_zero(struct bpf_reg_state *reg)
__mark_reg_known(reg, 0);
}
+static void __mark_reg_const_zero(struct bpf_reg_state *reg)
+{
+ __mark_reg_known(reg, 0);
+ reg->off = 0;
+ reg->type = SCALAR_VALUE;
+}
+
static void mark_reg_known_zero(struct bpf_verifier_env *env,
struct bpf_reg_state *regs, u32 regno)
{
@@ -560,6 +654,7 @@ static void __mark_reg_unknown(struct bpf_reg_state *reg)
reg->id = 0;
reg->off = 0;
reg->var_off = tnum_unknown;
+ reg->frameno = 0;
__mark_reg_unbounded(reg);
}
@@ -568,8 +663,8 @@ static void mark_reg_unknown(struct bpf_verifier_env *env,
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
verbose(env, "mark_reg_unknown(regs, %u)\n", regno);
- /* Something bad happened, let's kill all regs */
- for (regno = 0; regno < MAX_BPF_REG; regno++)
+ /* Something bad happened, let's kill all regs except FP */
+ for (regno = 0; regno < BPF_REG_FP; regno++)
__mark_reg_not_init(regs + regno);
return;
}
@@ -587,8 +682,8 @@ static void mark_reg_not_init(struct bpf_verifier_env *env,
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
verbose(env, "mark_reg_not_init(regs, %u)\n", regno);
- /* Something bad happened, let's kill all regs */
- for (regno = 0; regno < MAX_BPF_REG; regno++)
+ /* Something bad happened, let's kill all regs except FP */
+ for (regno = 0; regno < BPF_REG_FP; regno++)
__mark_reg_not_init(regs + regno);
return;
}
@@ -596,8 +691,9 @@ static void mark_reg_not_init(struct bpf_verifier_env *env,
}
static void init_reg_state(struct bpf_verifier_env *env,
- struct bpf_reg_state *regs)
+ struct bpf_func_state *state)
{
+ struct bpf_reg_state *regs = state->regs;
int i;
for (i = 0; i < MAX_BPF_REG; i++) {
@@ -608,41 +704,218 @@ static void init_reg_state(struct bpf_verifier_env *env,
/* frame pointer */
regs[BPF_REG_FP].type = PTR_TO_STACK;
mark_reg_known_zero(env, regs, BPF_REG_FP);
+ regs[BPF_REG_FP].frameno = state->frameno;
/* 1st arg to a function */
regs[BPF_REG_1].type = PTR_TO_CTX;
mark_reg_known_zero(env, regs, BPF_REG_1);
}
+#define BPF_MAIN_FUNC (-1)
+static void init_func_state(struct bpf_verifier_env *env,
+ struct bpf_func_state *state,
+ int callsite, int frameno, int subprogno)
+{
+ state->callsite = callsite;
+ state->frameno = frameno;
+ state->subprogno = subprogno;
+ init_reg_state(env, state);
+}
+
enum reg_arg_type {
SRC_OP, /* register is used as source operand */
DST_OP, /* register is used as destination operand */
DST_OP_NO_MARK /* same as above, check only, don't mark */
};
-static void mark_reg_read(const struct bpf_verifier_state *state, u32 regno)
+static int cmp_subprogs(const void *a, const void *b)
+{
+ return *(int *)a - *(int *)b;
+}
+
+static int find_subprog(struct bpf_verifier_env *env, int off)
{
- struct bpf_verifier_state *parent = state->parent;
+ u32 *p;
+
+ p = bsearch(&off, env->subprog_starts, env->subprog_cnt,
+ sizeof(env->subprog_starts[0]), cmp_subprogs);
+ if (!p)
+ return -ENOENT;
+ return p - env->subprog_starts;
+
+}
+
+static int add_subprog(struct bpf_verifier_env *env, int off)
+{
+ int insn_cnt = env->prog->len;
+ int ret;
+
+ if (off >= insn_cnt || off < 0) {
+ verbose(env, "call to invalid destination\n");
+ return -EINVAL;
+ }
+ ret = find_subprog(env, off);
+ if (ret >= 0)
+ return 0;
+ if (env->subprog_cnt >= BPF_MAX_SUBPROGS) {
+ verbose(env, "too many subprograms\n");
+ return -E2BIG;
+ }
+ env->subprog_starts[env->subprog_cnt++] = off;
+ sort(env->subprog_starts, env->subprog_cnt,
+ sizeof(env->subprog_starts[0]), cmp_subprogs, NULL);
+ return 0;
+}
+
+static int check_subprogs(struct bpf_verifier_env *env)
+{
+ int i, ret, subprog_start, subprog_end, off, cur_subprog = 0;
+ struct bpf_insn *insn = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+
+ /* determine subprog starts. The end is one before the next starts */
+ for (i = 0; i < insn_cnt; i++) {
+ if (insn[i].code != (BPF_JMP | BPF_CALL))
+ continue;
+ if (insn[i].src_reg != BPF_PSEUDO_CALL)
+ continue;
+ if (!env->allow_ptr_leaks) {
+ verbose(env, "function calls to other bpf functions are allowed for root only\n");
+ return -EPERM;
+ }
+ if (bpf_prog_is_dev_bound(env->prog->aux)) {
+ verbose(env, "function calls in offloaded programs are not supported yet\n");
+ return -EINVAL;
+ }
+ ret = add_subprog(env, i + insn[i].imm + 1);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (env->log.level > 1)
+ for (i = 0; i < env->subprog_cnt; i++)
+ verbose(env, "func#%d @%d\n", i, env->subprog_starts[i]);
+
+ /* now check that all jumps are within the same subprog */
+ subprog_start = 0;
+ if (env->subprog_cnt == cur_subprog)
+ subprog_end = insn_cnt;
+ else
+ subprog_end = env->subprog_starts[cur_subprog++];
+ for (i = 0; i < insn_cnt; i++) {
+ u8 code = insn[i].code;
+
+ if (BPF_CLASS(code) != BPF_JMP)
+ goto next;
+ if (BPF_OP(code) == BPF_EXIT || BPF_OP(code) == BPF_CALL)
+ goto next;
+ off = i + insn[i].off + 1;
+ if (off < subprog_start || off >= subprog_end) {
+ verbose(env, "jump out of range from insn %d to %d\n", i, off);
+ return -EINVAL;
+ }
+next:
+ if (i == subprog_end - 1) {
+ /* to avoid fall-through from one subprog into another
+ * the last insn of the subprog should be either exit
+ * or unconditional jump back
+ */
+ if (code != (BPF_JMP | BPF_EXIT) &&
+ code != (BPF_JMP | BPF_JA)) {
+ verbose(env, "last insn is not an exit or jmp\n");
+ return -EINVAL;
+ }
+ subprog_start = subprog_end;
+ if (env->subprog_cnt == cur_subprog)
+ subprog_end = insn_cnt;
+ else
+ subprog_end = env->subprog_starts[cur_subprog++];
+ }
+ }
+ return 0;
+}
+
+static
+struct bpf_verifier_state *skip_callee(struct bpf_verifier_env *env,
+ const struct bpf_verifier_state *state,
+ struct bpf_verifier_state *parent,
+ u32 regno)
+{
+ struct bpf_verifier_state *tmp = NULL;
+
+ /* 'parent' could be a state of caller and
+ * 'state' could be a state of callee. In such case
+ * parent->curframe < state->curframe
+ * and it's ok for r1 - r5 registers
+ *
+ * 'parent' could be a callee's state after it bpf_exit-ed.
+ * In such case parent->curframe > state->curframe
+ * and it's ok for r0 only
+ */
+ if (parent->curframe == state->curframe ||
+ (parent->curframe < state->curframe &&
+ regno >= BPF_REG_1 && regno <= BPF_REG_5) ||
+ (parent->curframe > state->curframe &&
+ regno == BPF_REG_0))
+ return parent;
+
+ if (parent->curframe > state->curframe &&
+ regno >= BPF_REG_6) {
+ /* for callee saved regs we have to skip the whole chain
+ * of states that belong to callee and mark as LIVE_READ
+ * the registers before the call
+ */
+ tmp = parent;
+ while (tmp && tmp->curframe != state->curframe) {
+ tmp = tmp->parent;
+ }
+ if (!tmp)
+ goto bug;
+ parent = tmp;
+ } else {
+ goto bug;
+ }
+ return parent;
+bug:
+ verbose(env, "verifier bug regno %d tmp %p\n", regno, tmp);
+ verbose(env, "regno %d parent frame %d current frame %d\n",
+ regno, parent->curframe, state->curframe);
+ return NULL;
+}
+
+static int mark_reg_read(struct bpf_verifier_env *env,
+ const struct bpf_verifier_state *state,
+ struct bpf_verifier_state *parent,
+ u32 regno)
+{
+ bool writes = parent == state->parent; /* Observe write marks */
if (regno == BPF_REG_FP)
/* We don't need to worry about FP liveness because it's read-only */
- return;
+ return 0;
while (parent) {
/* if read wasn't screened by an earlier write ... */
- if (state->regs[regno].live & REG_LIVE_WRITTEN)
+ if (writes && state->frame[state->curframe]->regs[regno].live & REG_LIVE_WRITTEN)
break;
+ parent = skip_callee(env, state, parent, regno);
+ if (!parent)
+ return -EFAULT;
/* ... then we depend on parent's value */
- parent->regs[regno].live |= REG_LIVE_READ;
+ parent->frame[parent->curframe]->regs[regno].live |= REG_LIVE_READ;
state = parent;
parent = state->parent;
+ writes = true;
}
+ return 0;
}
static int check_reg_arg(struct bpf_verifier_env *env, u32 regno,
enum reg_arg_type t)
{
- struct bpf_reg_state *regs = env->cur_state->regs;
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
+ struct bpf_reg_state *regs = state->regs;
if (regno >= MAX_BPF_REG) {
verbose(env, "R%d is invalid\n", regno);
@@ -655,7 +928,7 @@ static int check_reg_arg(struct bpf_verifier_env *env, u32 regno,
verbose(env, "R%d !read_ok\n", regno);
return -EACCES;
}
- mark_reg_read(env->cur_state, regno);
+ return mark_reg_read(env, vstate, vstate->parent, regno);
} else {
/* check whether register used as dest operand can be written to */
if (regno == BPF_REG_FP) {
@@ -686,17 +959,25 @@ static bool is_spillable_regtype(enum bpf_reg_type type)
}
}
+/* Does this register contain a constant zero? */
+static bool register_is_null(struct bpf_reg_state *reg)
+{
+ return reg->type == SCALAR_VALUE && tnum_equals_const(reg->var_off, 0);
+}
+
/* check_stack_read/write functions track spill/fill of registers,
* stack boundary and alignment are checked in check_mem_access()
*/
static int check_stack_write(struct bpf_verifier_env *env,
- struct bpf_verifier_state *state, int off,
- int size, int value_regno)
+ struct bpf_func_state *state, /* func where register points to */
+ int off, int size, int value_regno)
{
+ struct bpf_func_state *cur; /* state of the current function */
int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err;
+ enum bpf_reg_type type;
- err = realloc_verifier_state(state, round_up(slot + 1, BPF_REG_SIZE),
- true);
+ err = realloc_func_state(state, round_up(slot + 1, BPF_REG_SIZE),
+ true);
if (err)
return err;
/* caller checked that off % size == 0 and -MAX_BPF_STACK <= off < 0,
@@ -709,8 +990,9 @@ static int check_stack_write(struct bpf_verifier_env *env,
return -EACCES;
}
+ cur = env->cur_state->frame[env->cur_state->curframe];
if (value_regno >= 0 &&
- is_spillable_regtype(state->regs[value_regno].type)) {
+ is_spillable_regtype((type = cur->regs[value_regno].type))) {
/* register containing pointer is being spilled into stack */
if (size != BPF_REG_SIZE) {
@@ -718,51 +1000,116 @@ static int check_stack_write(struct bpf_verifier_env *env,
return -EACCES;
}
+ if (state != cur && type == PTR_TO_STACK) {
+ verbose(env, "cannot spill pointers to stack into stack frame of the caller\n");
+ return -EINVAL;
+ }
+
/* save register state */
- state->stack[spi].spilled_ptr = state->regs[value_regno];
+ state->stack[spi].spilled_ptr = cur->regs[value_regno];
state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN;
for (i = 0; i < BPF_REG_SIZE; i++)
state->stack[spi].slot_type[i] = STACK_SPILL;
} else {
+ u8 type = STACK_MISC;
+
/* regular write of data into stack */
state->stack[spi].spilled_ptr = (struct bpf_reg_state) {};
+ /* only mark the slot as written if all 8 bytes were written
+ * otherwise read propagation may incorrectly stop too soon
+ * when stack slots are partially written.
+ * This heuristic means that read propagation will be
+ * conservative, since it will add reg_live_read marks
+ * to stack slots all the way to first state when programs
+ * writes+reads less than 8 bytes
+ */
+ if (size == BPF_REG_SIZE)
+ state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN;
+
+ /* when we zero initialize stack slots mark them as such */
+ if (value_regno >= 0 &&
+ register_is_null(&cur->regs[value_regno]))
+ type = STACK_ZERO;
+
for (i = 0; i < size; i++)
state->stack[spi].slot_type[(slot - i) % BPF_REG_SIZE] =
- STACK_MISC;
+ type;
}
return 0;
}
-static void mark_stack_slot_read(const struct bpf_verifier_state *state, int slot)
+/* registers of every function are unique and mark_reg_read() propagates
+ * the liveness in the following cases:
+ * - from callee into caller for R1 - R5 that were used as arguments
+ * - from caller into callee for R0 that used as result of the call
+ * - from caller to the same caller skipping states of the callee for R6 - R9,
+ * since R6 - R9 are callee saved by implicit function prologue and
+ * caller's R6 != callee's R6, so when we propagate liveness up to
+ * parent states we need to skip callee states for R6 - R9.
+ *
+ * stack slot marking is different, since stacks of caller and callee are
+ * accessible in both (since caller can pass a pointer to caller's stack to
+ * callee which can pass it to another function), hence mark_stack_slot_read()
+ * has to propagate the stack liveness to all parent states at given frame number.
+ * Consider code:
+ * f1() {
+ * ptr = fp - 8;
+ * *ptr = ctx;
+ * call f2 {
+ * .. = *ptr;
+ * }
+ * .. = *ptr;
+ * }
+ * First *ptr is reading from f1's stack and mark_stack_slot_read() has
+ * to mark liveness at the f1's frame and not f2's frame.
+ * Second *ptr is also reading from f1's stack and mark_stack_slot_read() has
+ * to propagate liveness to f2 states at f1's frame level and further into
+ * f1 states at f1's frame level until write into that stack slot
+ */
+static void mark_stack_slot_read(struct bpf_verifier_env *env,
+ const struct bpf_verifier_state *state,
+ struct bpf_verifier_state *parent,
+ int slot, int frameno)
{
- struct bpf_verifier_state *parent = state->parent;
+ bool writes = parent == state->parent; /* Observe write marks */
while (parent) {
+ if (parent->frame[frameno]->allocated_stack <= slot * BPF_REG_SIZE)
+ /* since LIVE_WRITTEN mark is only done for full 8-byte
+ * write the read marks are conservative and parent
+ * state may not even have the stack allocated. In such case
+ * end the propagation, since the loop reached beginning
+ * of the function
+ */
+ break;
/* if read wasn't screened by an earlier write ... */
- if (state->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN)
+ if (writes && state->frame[frameno]->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN)
break;
/* ... then we depend on parent's value */
- parent->stack[slot].spilled_ptr.live |= REG_LIVE_READ;
+ parent->frame[frameno]->stack[slot].spilled_ptr.live |= REG_LIVE_READ;
state = parent;
parent = state->parent;
+ writes = true;
}
}
static int check_stack_read(struct bpf_verifier_env *env,
- struct bpf_verifier_state *state, int off, int size,
- int value_regno)
+ struct bpf_func_state *reg_state /* func where register points to */,
+ int off, int size, int value_regno)
{
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
int i, slot = -off - 1, spi = slot / BPF_REG_SIZE;
u8 *stype;
- if (state->allocated_stack <= slot) {
+ if (reg_state->allocated_stack <= slot) {
verbose(env, "invalid read from stack off %d+0 size %d\n",
off, size);
return -EACCES;
}
- stype = state->stack[spi].slot_type;
+ stype = reg_state->stack[spi].slot_type;
if (stype[0] == STACK_SPILL) {
if (size != BPF_REG_SIZE) {
@@ -778,21 +1125,44 @@ static int check_stack_read(struct bpf_verifier_env *env,
if (value_regno >= 0) {
/* restore register state from stack */
- state->regs[value_regno] = state->stack[spi].spilled_ptr;
- mark_stack_slot_read(state, spi);
+ state->regs[value_regno] = reg_state->stack[spi].spilled_ptr;
+ /* mark reg as written since spilled pointer state likely
+ * has its liveness marks cleared by is_state_visited()
+ * which resets stack/reg liveness for state transitions
+ */
+ state->regs[value_regno].live |= REG_LIVE_WRITTEN;
}
+ mark_stack_slot_read(env, vstate, vstate->parent, spi,
+ reg_state->frameno);
return 0;
} else {
+ int zeros = 0;
+
for (i = 0; i < size; i++) {
- if (stype[(slot - i) % BPF_REG_SIZE] != STACK_MISC) {
- verbose(env, "invalid read from stack off %d+%d size %d\n",
- off, i, size);
- return -EACCES;
+ if (stype[(slot - i) % BPF_REG_SIZE] == STACK_MISC)
+ continue;
+ if (stype[(slot - i) % BPF_REG_SIZE] == STACK_ZERO) {
+ zeros++;
+ continue;
+ }
+ verbose(env, "invalid read from stack off %d+%d size %d\n",
+ off, i, size);
+ return -EACCES;
+ }
+ mark_stack_slot_read(env, vstate, vstate->parent, spi,
+ reg_state->frameno);
+ if (value_regno >= 0) {
+ if (zeros == size) {
+ /* any size read into register is zero extended,
+ * so the whole register == const_zero
+ */
+ __mark_reg_const_zero(&state->regs[value_regno]);
+ } else {
+ /* have read misc data from the stack */
+ mark_reg_unknown(env, state->regs, value_regno);
}
+ state->regs[value_regno].live |= REG_LIVE_WRITTEN;
}
- if (value_regno >= 0)
- /* have read misc data from the stack */
- mark_reg_unknown(env, state->regs, value_regno);
return 0;
}
}
@@ -817,7 +1187,8 @@ static int __check_map_access(struct bpf_verifier_env *env, u32 regno, int off,
static int check_map_access(struct bpf_verifier_env *env, u32 regno,
int off, int size, bool zero_size_allowed)
{
- struct bpf_verifier_state *state = env->cur_state;
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *reg = &state->regs[regno];
int err;
@@ -1079,6 +1450,103 @@ static int check_ptr_alignment(struct bpf_verifier_env *env,
strict);
}
+static int update_stack_depth(struct bpf_verifier_env *env,
+ const struct bpf_func_state *func,
+ int off)
+{
+ u16 stack = env->subprog_stack_depth[func->subprogno];
+
+ if (stack >= -off)
+ return 0;
+
+ /* update known max for given subprogram */
+ env->subprog_stack_depth[func->subprogno] = -off;
+ return 0;
+}
+
+/* starting from main bpf function walk all instructions of the function
+ * and recursively walk all callees that given function can call.
+ * Ignore jump and exit insns.
+ * Since recursion is prevented by check_cfg() this algorithm
+ * only needs a local stack of MAX_CALL_FRAMES to remember callsites
+ */
+static int check_max_stack_depth(struct bpf_verifier_env *env)
+{
+ int depth = 0, frame = 0, subprog = 0, i = 0, subprog_end;
+ struct bpf_insn *insn = env->prog->insnsi;
+ int insn_cnt = env->prog->len;
+ int ret_insn[MAX_CALL_FRAMES];
+ int ret_prog[MAX_CALL_FRAMES];
+
+process_func:
+ /* round up to 32-bytes, since this is granularity
+ * of interpreter stack size
+ */
+ depth += round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32);
+ if (depth > MAX_BPF_STACK) {
+ verbose(env, "combined stack size of %d calls is %d. Too large\n",
+ frame + 1, depth);
+ return -EACCES;
+ }
+continue_func:
+ if (env->subprog_cnt == subprog)
+ subprog_end = insn_cnt;
+ else
+ subprog_end = env->subprog_starts[subprog];
+ for (; i < subprog_end; i++) {
+ if (insn[i].code != (BPF_JMP | BPF_CALL))
+ continue;
+ if (insn[i].src_reg != BPF_PSEUDO_CALL)
+ continue;
+ /* remember insn and function to return to */
+ ret_insn[frame] = i + 1;
+ ret_prog[frame] = subprog;
+
+ /* find the callee */
+ i = i + insn[i].imm + 1;
+ subprog = find_subprog(env, i);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ i);
+ return -EFAULT;
+ }
+ subprog++;
+ frame++;
+ if (frame >= MAX_CALL_FRAMES) {
+ WARN_ONCE(1, "verifier bug. Call stack is too deep\n");
+ return -EFAULT;
+ }
+ goto process_func;
+ }
+ /* end of for() loop means the last insn of the 'subprog'
+ * was reached. Doesn't matter whether it was JA or EXIT
+ */
+ if (frame == 0)
+ return 0;
+ depth -= round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32);
+ frame--;
+ i = ret_insn[frame];
+ subprog = ret_prog[frame];
+ goto continue_func;
+}
+
+#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+static int get_callee_stack_depth(struct bpf_verifier_env *env,
+ const struct bpf_insn *insn, int idx)
+{
+ int start = idx + insn->imm + 1, subprog;
+
+ subprog = find_subprog(env, start);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ start);
+ return -EFAULT;
+ }
+ subprog++;
+ return env->subprog_stack_depth[subprog];
+}
+#endif
+
/* truncate register to smaller size (in bytes)
* must be called with size < BPF_REG_SIZE
*/
@@ -1112,9 +1580,9 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
int bpf_size, enum bpf_access_type t,
int value_regno)
{
- struct bpf_verifier_state *state = env->cur_state;
struct bpf_reg_state *regs = cur_regs(env);
struct bpf_reg_state *reg = regs + regno;
+ struct bpf_func_state *state;
int size, err = 0;
size = bpf_size_to_bytes(bpf_size);
@@ -1203,8 +1671,10 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
return -EACCES;
}
- if (env->prog->aux->stack_depth < -off)
- env->prog->aux->stack_depth = -off;
+ state = func(env, reg);
+ err = update_stack_depth(env, state, off);
+ if (err)
+ return err;
if (t == BPF_WRITE)
err = check_stack_write(env, state, off, size,
@@ -1282,12 +1752,6 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins
BPF_SIZE(insn->code), BPF_WRITE, -1);
}
-/* Does this register contain a constant zero? */
-static bool register_is_null(struct bpf_reg_state reg)
-{
- return reg.type == SCALAR_VALUE && tnum_equals_const(reg.var_off, 0);
-}
-
/* when register 'regno' is passed into function that will read 'access_size'
* bytes from that pointer, make sure that it's within stack boundary
* and all elements of stack are initialized.
@@ -1298,32 +1762,32 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
int access_size, bool zero_size_allowed,
struct bpf_call_arg_meta *meta)
{
- struct bpf_verifier_state *state = env->cur_state;
- struct bpf_reg_state *regs = state->regs;
+ struct bpf_reg_state *reg = cur_regs(env) + regno;
+ struct bpf_func_state *state = func(env, reg);
int off, i, slot, spi;
- if (regs[regno].type != PTR_TO_STACK) {
+ if (reg->type != PTR_TO_STACK) {
/* Allow zero-byte read from NULL, regardless of pointer type */
if (zero_size_allowed && access_size == 0 &&
- register_is_null(regs[regno]))
+ register_is_null(reg))
return 0;
verbose(env, "R%d type=%s expected=%s\n", regno,
- reg_type_str[regs[regno].type],
+ reg_type_str[reg->type],
reg_type_str[PTR_TO_STACK]);
return -EACCES;
}
/* Only allow fixed-offset stack reads */
- if (!tnum_is_const(regs[regno].var_off)) {
+ if (!tnum_is_const(reg->var_off)) {
char tn_buf[48];
- tnum_strn(tn_buf, sizeof(tn_buf), regs[regno].var_off);
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
verbose(env, "invalid variable stack read R%d var_off=%s\n",
regno, tn_buf);
return -EACCES;
}
- off = regs[regno].off + regs[regno].var_off.value;
+ off = reg->off + reg->var_off.value;
if (off >= 0 || off < -MAX_BPF_STACK || off + access_size > 0 ||
access_size < 0 || (access_size == 0 && !zero_size_allowed)) {
verbose(env, "invalid stack type R%d off=%d access_size=%d\n",
@@ -1331,9 +1795,6 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
return -EACCES;
}
- if (env->prog->aux->stack_depth < -off)
- env->prog->aux->stack_depth = -off;
-
if (meta && meta->raw_mode) {
meta->access_size = access_size;
meta->regno = regno;
@@ -1341,17 +1802,32 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
}
for (i = 0; i < access_size; i++) {
+ u8 *stype;
+
slot = -(off + i) - 1;
spi = slot / BPF_REG_SIZE;
- if (state->allocated_stack <= slot ||
- state->stack[spi].slot_type[slot % BPF_REG_SIZE] !=
- STACK_MISC) {
- verbose(env, "invalid indirect read from stack off %d+%d size %d\n",
- off, i, access_size);
- return -EACCES;
+ if (state->allocated_stack <= slot)
+ goto err;
+ stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE];
+ if (*stype == STACK_MISC)
+ goto mark;
+ if (*stype == STACK_ZERO) {
+ /* helper can write anything into the stack */
+ *stype = STACK_MISC;
+ goto mark;
}
+err:
+ verbose(env, "invalid indirect read from stack off %d+%d size %d\n",
+ off, i, access_size);
+ return -EACCES;
+mark:
+ /* reading any byte out of 8-byte 'spill_slot' will cause
+ * the whole slot to be marked as 'read'
+ */
+ mark_stack_slot_read(env, env->cur_state, env->cur_state->parent,
+ spi, state->frameno);
}
- return 0;
+ return update_stack_depth(env, state, off);
}
static int check_helper_mem_access(struct bpf_verifier_env *env, int regno,
@@ -1374,6 +1850,19 @@ static int check_helper_mem_access(struct bpf_verifier_env *env, int regno,
}
}
+static bool arg_type_is_mem_ptr(enum bpf_arg_type type)
+{
+ return type == ARG_PTR_TO_MEM ||
+ type == ARG_PTR_TO_MEM_OR_NULL ||
+ type == ARG_PTR_TO_UNINIT_MEM;
+}
+
+static bool arg_type_is_mem_size(enum bpf_arg_type type)
+{
+ return type == ARG_CONST_SIZE ||
+ type == ARG_CONST_SIZE_OR_ZERO;
+}
+
static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
enum bpf_arg_type arg_type,
struct bpf_call_arg_meta *meta)
@@ -1423,15 +1912,13 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
expected_type = PTR_TO_CTX;
if (type != expected_type)
goto err_type;
- } else if (arg_type == ARG_PTR_TO_MEM ||
- arg_type == ARG_PTR_TO_MEM_OR_NULL ||
- arg_type == ARG_PTR_TO_UNINIT_MEM) {
+ } else if (arg_type_is_mem_ptr(arg_type)) {
expected_type = PTR_TO_STACK;
/* One exception here. In case function allows for NULL to be
* passed in as argument, it's a SCALAR_VALUE type. Final test
* happens during stack boundary checking.
*/
- if (register_is_null(*reg) &&
+ if (register_is_null(reg) &&
arg_type == ARG_PTR_TO_MEM_OR_NULL)
/* final test in check_stack_boundary() */;
else if (!type_is_pkt_pointer(type) &&
@@ -1486,25 +1973,12 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
err = check_stack_boundary(env, regno,
meta->map_ptr->value_size,
false, NULL);
- } else if (arg_type == ARG_CONST_SIZE ||
- arg_type == ARG_CONST_SIZE_OR_ZERO) {
+ } else if (arg_type_is_mem_size(arg_type)) {
bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO);
- /* bpf_xxx(..., buf, len) call will access 'len' bytes
- * from stack pointer 'buf'. Check it
- * note: regno == len, regno - 1 == buf
- */
- if (regno == 0) {
- /* kernel subsystem misconfigured verifier */
- verbose(env,
- "ARG_CONST_SIZE cannot be first argument\n");
- return -EACCES;
- }
-
/* The register is SCALAR_VALUE; the access check
* happens using its boundaries.
*/
-
if (!tnum_is_const(reg->var_off))
/* For unprivileged variable accesses, disable raw
* mode so that the program is required to
@@ -1604,6 +2078,10 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
case BPF_FUNC_tail_call:
if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY)
goto error;
+ if (env->subprog_cnt) {
+ verbose(env, "tail_calls are not allowed in programs with bpf-to-bpf calls\n");
+ return -EINVAL;
+ }
break;
case BPF_FUNC_perf_event_read:
case BPF_FUNC_perf_event_output:
@@ -1644,7 +2122,7 @@ error:
return -EINVAL;
}
-static int check_raw_mode(const struct bpf_func_proto *fn)
+static bool check_raw_mode_ok(const struct bpf_func_proto *fn)
{
int count = 0;
@@ -1659,15 +2137,52 @@ static int check_raw_mode(const struct bpf_func_proto *fn)
if (fn->arg5_type == ARG_PTR_TO_UNINIT_MEM)
count++;
- return count > 1 ? -EINVAL : 0;
+ /* We only support one arg being in raw mode at the moment,
+ * which is sufficient for the helper functions we have
+ * right now.
+ */
+ return count <= 1;
+}
+
+static bool check_args_pair_invalid(enum bpf_arg_type arg_curr,
+ enum bpf_arg_type arg_next)
+{
+ return (arg_type_is_mem_ptr(arg_curr) &&
+ !arg_type_is_mem_size(arg_next)) ||
+ (!arg_type_is_mem_ptr(arg_curr) &&
+ arg_type_is_mem_size(arg_next));
+}
+
+static bool check_arg_pair_ok(const struct bpf_func_proto *fn)
+{
+ /* bpf_xxx(..., buf, len) call will access 'len'
+ * bytes from memory 'buf'. Both arg types need
+ * to be paired, so make sure there's no buggy
+ * helper function specification.
+ */
+ if (arg_type_is_mem_size(fn->arg1_type) ||
+ arg_type_is_mem_ptr(fn->arg5_type) ||
+ check_args_pair_invalid(fn->arg1_type, fn->arg2_type) ||
+ check_args_pair_invalid(fn->arg2_type, fn->arg3_type) ||
+ check_args_pair_invalid(fn->arg3_type, fn->arg4_type) ||
+ check_args_pair_invalid(fn->arg4_type, fn->arg5_type))
+ return false;
+
+ return true;
+}
+
+static int check_func_proto(const struct bpf_func_proto *fn)
+{
+ return check_raw_mode_ok(fn) &&
+ check_arg_pair_ok(fn) ? 0 : -EINVAL;
}
/* Packet data might have moved, any old PTR_TO_PACKET[_META,_END]
* are now invalid, so turn them into unknown SCALAR_VALUE.
*/
-static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
+static void __clear_all_pkt_pointers(struct bpf_verifier_env *env,
+ struct bpf_func_state *state)
{
- struct bpf_verifier_state *state = env->cur_state;
struct bpf_reg_state *regs = state->regs, *reg;
int i;
@@ -1684,7 +2199,121 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
}
}
-static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
+static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
+{
+ struct bpf_verifier_state *vstate = env->cur_state;
+ int i;
+
+ for (i = 0; i <= vstate->curframe; i++)
+ __clear_all_pkt_pointers(env, vstate->frame[i]);
+}
+
+static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
+ int *insn_idx)
+{
+ struct bpf_verifier_state *state = env->cur_state;
+ struct bpf_func_state *caller, *callee;
+ int i, subprog, target_insn;
+
+ if (state->curframe + 1 >= MAX_CALL_FRAMES) {
+ verbose(env, "the call stack of %d frames is too deep\n",
+ state->curframe + 2);
+ return -E2BIG;
+ }
+
+ target_insn = *insn_idx + insn->imm;
+ subprog = find_subprog(env, target_insn + 1);
+ if (subprog < 0) {
+ verbose(env, "verifier bug. No program starts at insn %d\n",
+ target_insn + 1);
+ return -EFAULT;
+ }
+
+ caller = state->frame[state->curframe];
+ if (state->frame[state->curframe + 1]) {
+ verbose(env, "verifier bug. Frame %d already allocated\n",
+ state->curframe + 1);
+ return -EFAULT;
+ }
+
+ callee = kzalloc(sizeof(*callee), GFP_KERNEL);
+ if (!callee)
+ return -ENOMEM;
+ state->frame[state->curframe + 1] = callee;
+
+ /* callee cannot access r0, r6 - r9 for reading and has to write
+ * into its own stack before reading from it.
+ * callee can read/write into caller's stack
+ */
+ init_func_state(env, callee,
+ /* remember the callsite, it will be used by bpf_exit */
+ *insn_idx /* callsite */,
+ state->curframe + 1 /* frameno within this callchain */,
+ subprog + 1 /* subprog number within this prog */);
+
+ /* copy r1 - r5 args that callee can access */
+ for (i = BPF_REG_1; i <= BPF_REG_5; i++)
+ callee->regs[i] = caller->regs[i];
+
+ /* after the call regsiters r0 - r5 were scratched */
+ for (i = 0; i < CALLER_SAVED_REGS; i++) {
+ mark_reg_not_init(env, caller->regs, caller_saved[i]);
+ check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK);
+ }
+
+ /* only increment it after check_reg_arg() finished */
+ state->curframe++;
+
+ /* and go analyze first insn of the callee */
+ *insn_idx = target_insn;
+
+ if (env->log.level) {
+ verbose(env, "caller:\n");
+ print_verifier_state(env, caller);
+ verbose(env, "callee:\n");
+ print_verifier_state(env, callee);
+ }
+ return 0;
+}
+
+static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx)
+{
+ struct bpf_verifier_state *state = env->cur_state;
+ struct bpf_func_state *caller, *callee;
+ struct bpf_reg_state *r0;
+
+ callee = state->frame[state->curframe];
+ r0 = &callee->regs[BPF_REG_0];
+ if (r0->type == PTR_TO_STACK) {
+ /* technically it's ok to return caller's stack pointer
+ * (or caller's caller's pointer) back to the caller,
+ * since these pointers are valid. Only current stack
+ * pointer will be invalid as soon as function exits,
+ * but let's be conservative
+ */
+ verbose(env, "cannot return stack pointer to the caller\n");
+ return -EINVAL;
+ }
+
+ state->curframe--;
+ caller = state->frame[state->curframe];
+ /* return to the caller whatever r0 had in the callee */
+ caller->regs[BPF_REG_0] = *r0;
+
+ *insn_idx = callee->callsite + 1;
+ if (env->log.level) {
+ verbose(env, "returning from callee:\n");
+ print_verifier_state(env, callee);
+ verbose(env, "to caller at %d:\n", *insn_idx);
+ print_verifier_state(env, caller);
+ }
+ /* clear everything in the callee */
+ free_func_state(callee);
+ state->frame[state->curframe + 1] = NULL;
+ return 0;
+}
+
+static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
{
const struct bpf_func_proto *fn = NULL;
struct bpf_reg_state *regs;
@@ -1701,7 +2330,6 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
if (env->ops->get_func_proto)
fn = env->ops->get_func_proto(func_id);
-
if (!fn) {
verbose(env, "unknown func %s#%d\n", func_id_name(func_id),
func_id);
@@ -1725,10 +2353,7 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
memset(&meta, 0, sizeof(meta));
meta.pkt_access = fn->pkt_access;
- /* We only support one arg being in raw mode at the moment, which
- * is sufficient for the helper functions we have right now.
- */
- err = check_raw_mode(fn);
+ err = check_func_proto(fn);
if (err) {
verbose(env, "kernel subsystem misconfigured func %s#%d\n",
func_id_name(func_id), func_id);
@@ -1884,7 +2509,9 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
const struct bpf_reg_state *ptr_reg,
const struct bpf_reg_state *off_reg)
{
- struct bpf_reg_state *regs = cur_regs(env), *dst_reg;
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
+ struct bpf_reg_state *regs = state->regs, *dst_reg;
bool known = tnum_is_const(off_reg->var_off);
s64 smin_val = off_reg->smin_value, smax_val = off_reg->smax_value,
smin_ptr = ptr_reg->smin_value, smax_ptr = ptr_reg->smax_value;
@@ -2319,7 +2946,9 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env,
static int adjust_reg_min_max_vals(struct bpf_verifier_env *env,
struct bpf_insn *insn)
{
- struct bpf_reg_state *regs = cur_regs(env), *dst_reg, *src_reg;
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
+ struct bpf_reg_state *regs = state->regs, *dst_reg, *src_reg;
struct bpf_reg_state *ptr_reg = NULL, off_reg = {0};
u8 opcode = BPF_OP(insn->code);
@@ -2370,12 +2999,12 @@ static int adjust_reg_min_max_vals(struct bpf_verifier_env *env,
/* Got here implies adding two SCALAR_VALUEs */
if (WARN_ON_ONCE(ptr_reg)) {
- print_verifier_state(env, env->cur_state);
+ print_verifier_state(env, state);
verbose(env, "verifier internal error: unexpected ptr_reg\n");
return -EINVAL;
}
if (WARN_ON(!src_reg)) {
- print_verifier_state(env, env->cur_state);
+ print_verifier_state(env, state);
verbose(env, "verifier internal error: no src_reg\n");
return -EINVAL;
}
@@ -2537,14 +3166,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
return 0;
}
-static void find_good_pkt_pointers(struct bpf_verifier_state *state,
+static void find_good_pkt_pointers(struct bpf_verifier_state *vstate,
struct bpf_reg_state *dst_reg,
enum bpf_reg_type type,
bool range_right_open)
{
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *regs = state->regs, *reg;
u16 new_range;
- int i;
+ int i, j;
if (dst_reg->off < 0 ||
(dst_reg->off == 0 && range_right_open))
@@ -2614,12 +3244,15 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state,
/* keep the maximum range already checked */
regs[i].range = max(regs[i].range, new_range);
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] != STACK_SPILL)
- continue;
- reg = &state->stack[i].spilled_ptr;
- if (reg->type == type && reg->id == dst_reg->id)
- reg->range = max(reg->range, new_range);
+ for (j = 0; j <= vstate->curframe; j++) {
+ state = vstate->frame[j];
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
+ continue;
+ reg = &state->stack[i].spilled_ptr;
+ if (reg->type == type && reg->id == dst_reg->id)
+ reg->range = max(reg->range, new_range);
+ }
}
}
@@ -2857,20 +3490,24 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id,
/* The logic is similar to find_good_pkt_pointers(), both could eventually
* be folded together at some point.
*/
-static void mark_map_regs(struct bpf_verifier_state *state, u32 regno,
+static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno,
bool is_null)
{
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
struct bpf_reg_state *regs = state->regs;
u32 id = regs[regno].id;
- int i;
+ int i, j;
for (i = 0; i < MAX_BPF_REG; i++)
mark_map_reg(regs, i, id, is_null);
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
- if (state->stack[i].slot_type[0] != STACK_SPILL)
- continue;
- mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null);
+ for (j = 0; j <= vstate->curframe; j++) {
+ state = vstate->frame[j];
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
+ continue;
+ mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null);
+ }
}
}
@@ -2970,8 +3607,10 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn,
static int check_cond_jmp_op(struct bpf_verifier_env *env,
struct bpf_insn *insn, int *insn_idx)
{
- struct bpf_verifier_state *other_branch, *this_branch = env->cur_state;
- struct bpf_reg_state *regs = this_branch->regs, *dst_reg;
+ struct bpf_verifier_state *this_branch = env->cur_state;
+ struct bpf_verifier_state *other_branch;
+ struct bpf_reg_state *regs = this_branch->frame[this_branch->curframe]->regs;
+ struct bpf_reg_state *dst_reg, *other_branch_regs;
u8 opcode = BPF_OP(insn->code);
int err;
@@ -3014,8 +3653,9 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
if (BPF_SRC(insn->code) == BPF_K &&
(opcode == BPF_JEQ || opcode == BPF_JNE) &&
dst_reg->type == SCALAR_VALUE &&
- tnum_equals_const(dst_reg->var_off, insn->imm)) {
- if (opcode == BPF_JEQ) {
+ tnum_is_const(dst_reg->var_off)) {
+ if ((opcode == BPF_JEQ && dst_reg->var_off.value == insn->imm) ||
+ (opcode == BPF_JNE && dst_reg->var_off.value != insn->imm)) {
/* if (imm == imm) goto pc+off;
* only follow the goto, ignore fall-through
*/
@@ -3033,6 +3673,7 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
other_branch = push_stack(env, *insn_idx + insn->off + 1, *insn_idx);
if (!other_branch)
return -EFAULT;
+ other_branch_regs = other_branch->frame[other_branch->curframe]->regs;
/* detect if we are comparing against a constant value so we can adjust
* our min/max values for our dst register.
@@ -3045,22 +3686,22 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
if (dst_reg->type == SCALAR_VALUE &&
regs[insn->src_reg].type == SCALAR_VALUE) {
if (tnum_is_const(regs[insn->src_reg].var_off))
- reg_set_min_max(&other_branch->regs[insn->dst_reg],
+ reg_set_min_max(&other_branch_regs[insn->dst_reg],
dst_reg, regs[insn->src_reg].var_off.value,
opcode);
else if (tnum_is_const(dst_reg->var_off))
- reg_set_min_max_inv(&other_branch->regs[insn->src_reg],
+ reg_set_min_max_inv(&other_branch_regs[insn->src_reg],
&regs[insn->src_reg],
dst_reg->var_off.value, opcode);
else if (opcode == BPF_JEQ || opcode == BPF_JNE)
/* Comparing for equality, we can combine knowledge */
- reg_combine_min_max(&other_branch->regs[insn->src_reg],
- &other_branch->regs[insn->dst_reg],
+ reg_combine_min_max(&other_branch_regs[insn->src_reg],
+ &other_branch_regs[insn->dst_reg],
&regs[insn->src_reg],
&regs[insn->dst_reg], opcode);
}
} else if (dst_reg->type == SCALAR_VALUE) {
- reg_set_min_max(&other_branch->regs[insn->dst_reg],
+ reg_set_min_max(&other_branch_regs[insn->dst_reg],
dst_reg, insn->imm, opcode);
}
@@ -3081,7 +3722,7 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
return -EACCES;
}
if (env->log.level)
- print_verifier_state(env, this_branch);
+ print_verifier_state(env, this_branch->frame[this_branch->curframe]);
return 0;
}
@@ -3166,6 +3807,18 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
return -EINVAL;
}
+ if (env->subprog_cnt) {
+ /* when program has LD_ABS insn JITs and interpreter assume
+ * that r1 == ctx == skb which is not the case for callees
+ * that can have arbitrary arguments. It's problematic
+ * for main prog as well since JITs would need to analyze
+ * all functions in order to make proper register save/restore
+ * decisions in the main prog. Hence disallow LD_ABS with calls
+ */
+ verbose(env, "BPF_LD_[ABS|IND] instructions cannot be mixed with bpf-to-bpf calls\n");
+ return -EINVAL;
+ }
+
if (insn->dst_reg != BPF_REG_0 || insn->off != 0 ||
BPF_SIZE(insn->code) == BPF_DW ||
(mode == BPF_ABS && insn->src_reg != BPF_REG_0)) {
@@ -3342,6 +3995,10 @@ static int check_cfg(struct bpf_verifier_env *env)
int ret = 0;
int i, t;
+ ret = check_subprogs(env);
+ if (ret < 0)
+ return ret;
+
insn_state = kcalloc(insn_cnt, sizeof(int), GFP_KERNEL);
if (!insn_state)
return -ENOMEM;
@@ -3374,6 +4031,14 @@ peek_stack:
goto err_free;
if (t + 1 < insn_cnt)
env->explored_states[t + 1] = STATE_LIST_MARK;
+ if (insns[t].src_reg == BPF_PSEUDO_CALL) {
+ env->explored_states[t] = STATE_LIST_MARK;
+ ret = push_insn(t, t + insns[t].imm + 1, BRANCH, env);
+ if (ret == 1)
+ goto peek_stack;
+ else if (ret < 0)
+ goto err_free;
+ }
} else if (opcode == BPF_JA) {
if (BPF_SRC(insns[t].code) != BPF_K) {
ret = -EINVAL;
@@ -3492,11 +4157,21 @@ static bool check_ids(u32 old_id, u32 cur_id, struct idpair *idmap)
static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
struct idpair *idmap)
{
+ bool equal;
+
if (!(rold->live & REG_LIVE_READ))
/* explored state didn't use this */
return true;
- if (memcmp(rold, rcur, offsetof(struct bpf_reg_state, live)) == 0)
+ equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, frameno)) == 0;
+
+ if (rold->type == PTR_TO_STACK)
+ /* two stack pointers are equal only if they're pointing to
+ * the same stack frame, since fp-8 in foo != fp-8 in bar
+ */
+ return equal && rold->frameno == rcur->frameno;
+
+ if (equal)
return true;
if (rold->type == NOT_INIT)
@@ -3568,7 +4243,6 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
tnum_in(rold->var_off, rcur->var_off);
case PTR_TO_CTX:
case CONST_PTR_TO_MAP:
- case PTR_TO_STACK:
case PTR_TO_PACKET_END:
/* Only valid matches are exact, which memcmp() above
* would have accepted
@@ -3583,8 +4257,8 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur,
return false;
}
-static bool stacksafe(struct bpf_verifier_state *old,
- struct bpf_verifier_state *cur,
+static bool stacksafe(struct bpf_func_state *old,
+ struct bpf_func_state *cur,
struct idpair *idmap)
{
int i, spi;
@@ -3602,8 +4276,19 @@ static bool stacksafe(struct bpf_verifier_state *old,
for (i = 0; i < old->allocated_stack; i++) {
spi = i / BPF_REG_SIZE;
+ if (!(old->stack[spi].spilled_ptr.live & REG_LIVE_READ))
+ /* explored state didn't use this */
+ continue;
+
if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_INVALID)
continue;
+ /* if old state was safe with misc data in the stack
+ * it will be safe with zero-initialized stack.
+ * The opposite is not true
+ */
+ if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_MISC &&
+ cur->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_ZERO)
+ continue;
if (old->stack[spi].slot_type[i % BPF_REG_SIZE] !=
cur->stack[spi].slot_type[i % BPF_REG_SIZE])
/* Ex: old explored (safe) state has STACK_SPILL in
@@ -3660,9 +4345,8 @@ static bool stacksafe(struct bpf_verifier_state *old,
* whereas register type in current state is meaningful, it means that
* the current state will reach 'bpf_exit' instruction safely
*/
-static bool states_equal(struct bpf_verifier_env *env,
- struct bpf_verifier_state *old,
- struct bpf_verifier_state *cur)
+static bool func_states_equal(struct bpf_func_state *old,
+ struct bpf_func_state *cur)
{
struct idpair *idmap;
bool ret = false;
@@ -3686,71 +4370,72 @@ out_free:
return ret;
}
+static bool states_equal(struct bpf_verifier_env *env,
+ struct bpf_verifier_state *old,
+ struct bpf_verifier_state *cur)
+{
+ int i;
+
+ if (old->curframe != cur->curframe)
+ return false;
+
+ /* for states to be equal callsites have to be the same
+ * and all frame states need to be equivalent
+ */
+ for (i = 0; i <= old->curframe; i++) {
+ if (old->frame[i]->callsite != cur->frame[i]->callsite)
+ return false;
+ if (!func_states_equal(old->frame[i], cur->frame[i]))
+ return false;
+ }
+ return true;
+}
+
/* A write screens off any subsequent reads; but write marks come from the
- * straight-line code between a state and its parent. When we arrive at a
- * jump target (in the first iteration of the propagate_liveness() loop),
- * we didn't arrive by the straight-line code, so read marks in state must
- * propagate to parent regardless of state's write marks.
+ * straight-line code between a state and its parent. When we arrive at an
+ * equivalent state (jump target or such) we didn't arrive by the straight-line
+ * code, so read marks in the state must propagate to the parent regardless
+ * of the state's write marks. That's what 'parent == state->parent' comparison
+ * in mark_reg_read() and mark_stack_slot_read() is for.
*/
-static bool do_propagate_liveness(const struct bpf_verifier_state *state,
- struct bpf_verifier_state *parent)
+static int propagate_liveness(struct bpf_verifier_env *env,
+ const struct bpf_verifier_state *vstate,
+ struct bpf_verifier_state *vparent)
{
- bool writes = parent == state->parent; /* Observe write marks */
- bool touched = false; /* any changes made? */
- int i;
+ int i, frame, err = 0;
+ struct bpf_func_state *state, *parent;
- if (!parent)
- return touched;
+ if (vparent->curframe != vstate->curframe) {
+ WARN(1, "propagate_live: parent frame %d current frame %d\n",
+ vparent->curframe, vstate->curframe);
+ return -EFAULT;
+ }
/* Propagate read liveness of registers... */
BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
/* We don't need to worry about FP liveness because it's read-only */
for (i = 0; i < BPF_REG_FP; i++) {
- if (parent->regs[i].live & REG_LIVE_READ)
+ if (vparent->frame[vparent->curframe]->regs[i].live & REG_LIVE_READ)
continue;
- if (writes && (state->regs[i].live & REG_LIVE_WRITTEN))
- continue;
- if (state->regs[i].live & REG_LIVE_READ) {
- parent->regs[i].live |= REG_LIVE_READ;
- touched = true;
+ if (vstate->frame[vstate->curframe]->regs[i].live & REG_LIVE_READ) {
+ err = mark_reg_read(env, vstate, vparent, i);
+ if (err)
+ return err;
}
}
+
/* ... and stack slots */
- for (i = 0; i < state->allocated_stack / BPF_REG_SIZE &&
- i < parent->allocated_stack / BPF_REG_SIZE; i++) {
- if (parent->stack[i].slot_type[0] != STACK_SPILL)
- continue;
- if (state->stack[i].slot_type[0] != STACK_SPILL)
- continue;
- if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ)
- continue;
- if (writes &&
- (state->stack[i].spilled_ptr.live & REG_LIVE_WRITTEN))
- continue;
- if (state->stack[i].spilled_ptr.live & REG_LIVE_READ) {
- parent->stack[i].spilled_ptr.live |= REG_LIVE_READ;
- touched = true;
+ for (frame = 0; frame <= vstate->curframe; frame++) {
+ state = vstate->frame[frame];
+ parent = vparent->frame[frame];
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE &&
+ i < parent->allocated_stack / BPF_REG_SIZE; i++) {
+ if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ)
+ continue;
+ if (state->stack[i].spilled_ptr.live & REG_LIVE_READ)
+ mark_stack_slot_read(env, vstate, vparent, i, frame);
}
}
- return touched;
-}
-
-/* "parent" is "a state from which we reach the current state", but initially
- * it is not the state->parent (i.e. "the state whose straight-line code leads
- * to the current state"), instead it is the state that happened to arrive at
- * a (prunable) equivalent of the current state. See comment above
- * do_propagate_liveness() for consequences of this.
- * This function is just a more efficient way of calling mark_reg_read() or
- * mark_stack_slot_read() on each reg in "parent" that is read in "state",
- * though it requires that parent != state->parent in the call arguments.
- */
-static void propagate_liveness(const struct bpf_verifier_state *state,
- struct bpf_verifier_state *parent)
-{
- while (do_propagate_liveness(state, parent)) {
- /* Something changed, so we need to feed those changes onward */
- state = parent;
- parent = state->parent;
- }
+ return err;
}
static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
@@ -3758,7 +4443,7 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
struct bpf_verifier_state_list *new_sl;
struct bpf_verifier_state_list *sl;
struct bpf_verifier_state *cur = env->cur_state;
- int i, err;
+ int i, j, err;
sl = env->explored_states[insn_idx];
if (!sl)
@@ -3779,7 +4464,9 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
* they'll be immediately forgotten as we're pruning
* this state and will pop a new one.
*/
- propagate_liveness(&sl->state, cur);
+ err = propagate_liveness(env, &sl->state, cur);
+ if (err)
+ return err;
return 1;
}
sl = sl->next;
@@ -3787,9 +4474,10 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
/* there were no equivalent states, remember current one.
* technically the current state is not proven to be safe yet,
- * but it will either reach bpf_exit (which means it's safe) or
- * it will be rejected. Since there are no loops, we won't be
- * seeing this 'insn_idx' instruction again on the way to bpf_exit
+ * but it will either reach outer most bpf_exit (which means it's safe)
+ * or it will be rejected. Since there are no loops, we won't be
+ * seeing this tuple (frame[0].callsite, frame[1].callsite, .. insn_idx)
+ * again on the way to bpf_exit
*/
new_sl = kzalloc(sizeof(struct bpf_verifier_state_list), GFP_KERNEL);
if (!new_sl)
@@ -3813,19 +4501,15 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
* explored_states can get read marks.)
*/
for (i = 0; i < BPF_REG_FP; i++)
- cur->regs[i].live = REG_LIVE_NONE;
- for (i = 0; i < cur->allocated_stack / BPF_REG_SIZE; i++)
- if (cur->stack[i].slot_type[0] == STACK_SPILL)
- cur->stack[i].spilled_ptr.live = REG_LIVE_NONE;
- return 0;
-}
+ cur->frame[cur->curframe]->regs[i].live = REG_LIVE_NONE;
-static int ext_analyzer_insn_hook(struct bpf_verifier_env *env,
- int insn_idx, int prev_insn_idx)
-{
- if (env->dev_ops && env->dev_ops->insn_hook)
- return env->dev_ops->insn_hook(env, insn_idx, prev_insn_idx);
+ /* all stack frames are accessible from callee, clear them all */
+ for (j = 0; j <= cur->curframe; j++) {
+ struct bpf_func_state *frame = cur->frame[j];
+ for (i = 0; i < frame->allocated_stack / BPF_REG_SIZE; i++)
+ frame->stack[i].spilled_ptr.live = REG_LIVE_NONE;
+ }
return 0;
}
@@ -3834,7 +4518,7 @@ static int do_check(struct bpf_verifier_env *env)
struct bpf_verifier_state *state;
struct bpf_insn *insns = env->prog->insnsi;
struct bpf_reg_state *regs;
- int insn_cnt = env->prog->len;
+ int insn_cnt = env->prog->len, i;
int insn_idx, prev_insn_idx = 0;
int insn_processed = 0;
bool do_print_state = false;
@@ -3842,9 +4526,18 @@ static int do_check(struct bpf_verifier_env *env)
state = kzalloc(sizeof(struct bpf_verifier_state), GFP_KERNEL);
if (!state)
return -ENOMEM;
- env->cur_state = state;
- init_reg_state(env, state->regs);
+ state->curframe = 0;
state->parent = NULL;
+ state->frame[0] = kzalloc(sizeof(struct bpf_func_state), GFP_KERNEL);
+ if (!state->frame[0]) {
+ kfree(state);
+ return -ENOMEM;
+ }
+ env->cur_state = state;
+ init_func_state(env, state->frame[0],
+ BPF_MAIN_FUNC /* callsite */,
+ 0 /* frameno */,
+ 0 /* subprogno, zero == main subprog */);
insn_idx = 0;
for (;;) {
struct bpf_insn *insn;
@@ -3891,19 +4584,25 @@ static int do_check(struct bpf_verifier_env *env)
else
verbose(env, "\nfrom %d to %d:",
prev_insn_idx, insn_idx);
- print_verifier_state(env, state);
+ print_verifier_state(env, state->frame[state->curframe]);
do_print_state = false;
}
if (env->log.level) {
+ const struct bpf_insn_cbs cbs = {
+ .cb_print = verbose,
+ };
+
verbose(env, "%d: ", insn_idx);
- print_bpf_insn(verbose, env, insn,
- env->allow_ptr_leaks);
+ print_bpf_insn(&cbs, env, insn, env->allow_ptr_leaks);
}
- err = ext_analyzer_insn_hook(env, insn_idx, prev_insn_idx);
- if (err)
- return err;
+ if (bpf_prog_is_dev_bound(env->prog->aux)) {
+ err = bpf_prog_offload_verify_insn(env, insn_idx,
+ prev_insn_idx);
+ if (err)
+ return err;
+ }
regs = cur_regs(env);
env->insn_aux_data[insn_idx].seen = true;
@@ -4030,13 +4729,17 @@ static int do_check(struct bpf_verifier_env *env)
if (opcode == BPF_CALL) {
if (BPF_SRC(insn->code) != BPF_K ||
insn->off != 0 ||
- insn->src_reg != BPF_REG_0 ||
+ (insn->src_reg != BPF_REG_0 &&
+ insn->src_reg != BPF_PSEUDO_CALL) ||
insn->dst_reg != BPF_REG_0) {
verbose(env, "BPF_CALL uses reserved fields\n");
return -EINVAL;
}
- err = check_call(env, insn->imm, insn_idx);
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ err = check_func_call(env, insn, &insn_idx);
+ else
+ err = check_helper_call(env, insn->imm, insn_idx);
if (err)
return err;
@@ -4061,6 +4764,16 @@ static int do_check(struct bpf_verifier_env *env)
return -EINVAL;
}
+ if (state->curframe) {
+ /* exit from nested function */
+ prev_insn_idx = insn_idx;
+ err = prepare_func_exit(env, &insn_idx);
+ if (err)
+ return err;
+ do_print_state = true;
+ continue;
+ }
+
/* eBPF calling convetion is such that R0 is used
* to return the value from eBPF program.
* Make sure that it's readable at this time
@@ -4121,8 +4834,17 @@ process_bpf_exit:
insn_idx++;
}
- verbose(env, "processed %d insns, stack depth %d\n", insn_processed,
- env->prog->aux->stack_depth);
+ verbose(env, "processed %d insns (limit %d), stack depth ",
+ insn_processed, BPF_COMPLEXITY_LIMIT_INSNS);
+ for (i = 0; i < env->subprog_cnt + 1; i++) {
+ u32 depth = env->subprog_stack_depth[i];
+
+ verbose(env, "%d", depth);
+ if (i + 1 < env->subprog_cnt + 1)
+ verbose(env, "+");
+ }
+ verbose(env, "\n");
+ env->prog->aux->stack_depth = env->subprog_stack_depth[0];
return 0;
}
@@ -4155,6 +4877,13 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
return -EINVAL;
}
}
+
+ if ((bpf_prog_is_dev_bound(prog->aux) || bpf_map_is_dev_bound(map)) &&
+ !bpf_offload_dev_match(prog, map)) {
+ verbose(env, "offload device mismatch between prog and map\n");
+ return -EINVAL;
+ }
+
return 0;
}
@@ -4252,6 +4981,13 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env)
next_insn:
insn++;
i++;
+ continue;
+ }
+
+ /* Basic sanity check before we invest more work here. */
+ if (!bpf_opcode_in_insntable(insn->code)) {
+ verbose(env, "unknown opcode %02x\n", insn->code);
+ return -EINVAL;
}
}
@@ -4308,6 +5044,19 @@ static int adjust_insn_aux_data(struct bpf_verifier_env *env, u32 prog_len,
return 0;
}
+static void adjust_subprog_starts(struct bpf_verifier_env *env, u32 off, u32 len)
+{
+ int i;
+
+ if (len == 1)
+ return;
+ for (i = 0; i < env->subprog_cnt; i++) {
+ if (env->subprog_starts[i] < off)
+ continue;
+ env->subprog_starts[i] += len - 1;
+ }
+}
+
static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off,
const struct bpf_insn *patch, u32 len)
{
@@ -4318,17 +5067,25 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of
return NULL;
if (adjust_insn_aux_data(env, new_prog->len, off, len))
return NULL;
+ adjust_subprog_starts(env, off, len);
return new_prog;
}
-/* The verifier does more data flow analysis than llvm and will not explore
- * branches that are dead at run time. Malicious programs can have dead code
- * too. Therefore replace all dead at-run-time code with nops.
+/* The verifier does more data flow analysis than llvm and will not
+ * explore branches that are dead at run time. Malicious programs can
+ * have dead code too. Therefore replace all dead at-run-time code
+ * with 'ja -1'.
+ *
+ * Just nops are not optimal, e.g. if they would sit at the end of the
+ * program and through another bug we would manage to jump there, then
+ * we'd execute beyond program memory otherwise. Returning exception
+ * code also wouldn't work since we can have subprogs where the dead
+ * code could be located.
*/
static void sanitize_dead_code(struct bpf_verifier_env *env)
{
struct bpf_insn_aux_data *aux_data = env->insn_aux_data;
- struct bpf_insn nop = BPF_MOV64_REG(BPF_REG_0, BPF_REG_0);
+ struct bpf_insn trap = BPF_JMP_IMM(BPF_JA, 0, 0, -1);
struct bpf_insn *insn = env->prog->insnsi;
const int insn_cnt = env->prog->len;
int i;
@@ -4336,7 +5093,7 @@ static void sanitize_dead_code(struct bpf_verifier_env *env)
for (i = 0; i < insn_cnt; i++) {
if (aux_data[i].seen)
continue;
- memcpy(insn + i, &nop, sizeof(nop));
+ memcpy(insn + i, &trap, sizeof(trap));
}
}
@@ -4452,6 +5209,180 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
return 0;
}
+static int jit_subprogs(struct bpf_verifier_env *env)
+{
+ struct bpf_prog *prog = env->prog, **func, *tmp;
+ int i, j, subprog_start, subprog_end = 0, len, subprog;
+ struct bpf_insn *insn;
+ void *old_bpf_func;
+ int err = -ENOMEM;
+
+ if (env->subprog_cnt == 0)
+ return 0;
+
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ subprog = find_subprog(env, i + insn->imm + 1);
+ if (subprog < 0) {
+ WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
+ i + insn->imm + 1);
+ return -EFAULT;
+ }
+ /* temporarily remember subprog id inside insn instead of
+ * aux_data, since next loop will split up all insns into funcs
+ */
+ insn->off = subprog + 1;
+ /* remember original imm in case JIT fails and fallback
+ * to interpreter will be needed
+ */
+ env->insn_aux_data[i].call_imm = insn->imm;
+ /* point imm to __bpf_call_base+1 from JITs point of view */
+ insn->imm = 1;
+ }
+
+ func = kzalloc(sizeof(prog) * (env->subprog_cnt + 1), GFP_KERNEL);
+ if (!func)
+ return -ENOMEM;
+
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ subprog_start = subprog_end;
+ if (env->subprog_cnt == i)
+ subprog_end = prog->len;
+ else
+ subprog_end = env->subprog_starts[i];
+
+ len = subprog_end - subprog_start;
+ func[i] = bpf_prog_alloc(bpf_prog_size(len), GFP_USER);
+ if (!func[i])
+ goto out_free;
+ memcpy(func[i]->insnsi, &prog->insnsi[subprog_start],
+ len * sizeof(struct bpf_insn));
+ func[i]->type = prog->type;
+ func[i]->len = len;
+ if (bpf_prog_calc_tag(func[i]))
+ goto out_free;
+ func[i]->is_func = 1;
+ /* Use bpf_prog_F_tag to indicate functions in stack traces.
+ * Long term would need debug info to populate names
+ */
+ func[i]->aux->name[0] = 'F';
+ func[i]->aux->stack_depth = env->subprog_stack_depth[i];
+ func[i]->jit_requested = 1;
+ func[i] = bpf_int_jit_compile(func[i]);
+ if (!func[i]->jited) {
+ err = -ENOTSUPP;
+ goto out_free;
+ }
+ cond_resched();
+ }
+ /* at this point all bpf functions were successfully JITed
+ * now populate all bpf_calls with correct addresses and
+ * run last pass of JIT
+ */
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ insn = func[i]->insnsi;
+ for (j = 0; j < func[i]->len; j++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ subprog = insn->off;
+ insn->off = 0;
+ insn->imm = (u64 (*)(u64, u64, u64, u64, u64))
+ func[subprog]->bpf_func -
+ __bpf_call_base;
+ }
+ }
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ old_bpf_func = func[i]->bpf_func;
+ tmp = bpf_int_jit_compile(func[i]);
+ if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) {
+ verbose(env, "JIT doesn't support bpf-to-bpf calls\n");
+ err = -EFAULT;
+ goto out_free;
+ }
+ cond_resched();
+ }
+
+ /* finally lock prog and jit images for all functions and
+ * populate kallsysm
+ */
+ for (i = 0; i <= env->subprog_cnt; i++) {
+ bpf_prog_lock_ro(func[i]);
+ bpf_prog_kallsyms_add(func[i]);
+ }
+
+ /* Last step: make now unused interpreter insns from main
+ * prog consistent for later dump requests, so they can
+ * later look the same as if they were interpreted only.
+ */
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ unsigned long addr;
+
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ insn->off = env->insn_aux_data[i].call_imm;
+ subprog = find_subprog(env, i + insn->off + 1);
+ addr = (unsigned long)func[subprog + 1]->bpf_func;
+ addr &= PAGE_MASK;
+ insn->imm = (u64 (*)(u64, u64, u64, u64, u64))
+ addr - __bpf_call_base;
+ }
+
+ prog->jited = 1;
+ prog->bpf_func = func[0]->bpf_func;
+ prog->aux->func = func;
+ prog->aux->func_cnt = env->subprog_cnt + 1;
+ return 0;
+out_free:
+ for (i = 0; i <= env->subprog_cnt; i++)
+ if (func[i])
+ bpf_jit_free(func[i]);
+ kfree(func);
+ /* cleanup main prog to be interpreted */
+ prog->jit_requested = 0;
+ for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ insn->off = 0;
+ insn->imm = env->insn_aux_data[i].call_imm;
+ }
+ return err;
+}
+
+static int fixup_call_args(struct bpf_verifier_env *env)
+{
+#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+ struct bpf_prog *prog = env->prog;
+ struct bpf_insn *insn = prog->insnsi;
+ int i, depth;
+#endif
+ int err;
+
+ err = 0;
+ if (env->prog->jit_requested) {
+ err = jit_subprogs(env);
+ if (err == 0)
+ return 0;
+ }
+#ifndef CONFIG_BPF_JIT_ALWAYS_ON
+ for (i = 0; i < prog->len; i++, insn++) {
+ if (insn->code != (BPF_JMP | BPF_CALL) ||
+ insn->src_reg != BPF_PSEUDO_CALL)
+ continue;
+ depth = get_callee_stack_depth(env, insn, i);
+ if (depth < 0)
+ return depth;
+ bpf_patch_call_args(insn, depth);
+ }
+ err = 0;
+#endif
+ return err;
+}
+
/* fixup insn->imm field of bpf_call instructions
* and inline eligible helpers as explicit sequence of BPF instructions
*
@@ -4469,15 +5400,37 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
int i, cnt, delta = 0;
for (i = 0; i < insn_cnt; i++, insn++) {
- if (insn->code == (BPF_ALU | BPF_MOD | BPF_X) ||
+ if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) ||
+ insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
+ insn->code == (BPF_ALU | BPF_MOD | BPF_X) ||
insn->code == (BPF_ALU | BPF_DIV | BPF_X)) {
- /* due to JIT bugs clear upper 32-bits of src register
- * before div/mod operation
- */
- insn_buf[0] = BPF_MOV32_REG(insn->src_reg, insn->src_reg);
- insn_buf[1] = *insn;
- cnt = 2;
- new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
+ bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
+ struct bpf_insn mask_and_div[] = {
+ BPF_MOV32_REG(insn->src_reg, insn->src_reg),
+ /* Rx div 0 -> 0 */
+ BPF_JMP_IMM(BPF_JNE, insn->src_reg, 0, 2),
+ BPF_ALU32_REG(BPF_XOR, insn->dst_reg, insn->dst_reg),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+ *insn,
+ };
+ struct bpf_insn mask_and_mod[] = {
+ BPF_MOV32_REG(insn->src_reg, insn->src_reg),
+ /* Rx mod 0 -> Rx */
+ BPF_JMP_IMM(BPF_JEQ, insn->src_reg, 0, 1),
+ *insn,
+ };
+ struct bpf_insn *patchlet;
+
+ if (insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
+ insn->code == (BPF_ALU | BPF_DIV | BPF_X)) {
+ patchlet = mask_and_div + (is64 ? 1 : 0);
+ cnt = ARRAY_SIZE(mask_and_div) - (is64 ? 1 : 0);
+ } else {
+ patchlet = mask_and_mod + (is64 ? 1 : 0);
+ cnt = ARRAY_SIZE(mask_and_mod) - (is64 ? 1 : 0);
+ }
+
+ new_prog = bpf_patch_insn_data(env, i + delta, patchlet, cnt);
if (!new_prog)
return -ENOMEM;
@@ -4489,11 +5442,15 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
if (insn->code != (BPF_JMP | BPF_CALL))
continue;
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ continue;
if (insn->imm == BPF_FUNC_get_route_realm)
prog->dst_needed = 1;
if (insn->imm == BPF_FUNC_get_prandom_u32)
bpf_user_rnd_init_once();
+ if (insn->imm == BPF_FUNC_override_return)
+ prog->kprobe_override = 1;
if (insn->imm == BPF_FUNC_tail_call) {
/* If we tail call into other programs, we
* cannot make any assumptions since they can
@@ -4545,7 +5502,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
/* BPF_EMIT_CALL() assumptions in some of the map_gen_lookup
* handlers are currently limited to 64 bit only.
*/
- if (ebpf_jit_enabled() && BITS_PER_LONG == 64 &&
+ if (prog->jit_requested && BITS_PER_LONG == 64 &&
insn->imm == BPF_FUNC_map_lookup_elem) {
map_ptr = env->insn_aux_data[i + delta].map_ptr;
if (map_ptr == BPF_MAP_PTR_POISON ||
@@ -4680,7 +5637,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
env->strict_alignment = true;
- if (env->prog->aux->offload) {
+ if (bpf_prog_is_dev_bound(env->prog->aux)) {
ret = bpf_prog_offload_verifier_prep(env);
if (ret)
goto err_unlock;
@@ -4697,12 +5654,12 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
if (!env->explored_states)
goto skip_full_check;
+ env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
+
ret = check_cfg(env);
if (ret < 0)
goto skip_full_check;
- env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
-
ret = do_check(env);
if (env->cur_state) {
free_verifier_state(env->cur_state, true);
@@ -4717,12 +5674,18 @@ skip_full_check:
sanitize_dead_code(env);
if (ret == 0)
+ ret = check_max_stack_depth(env);
+
+ if (ret == 0)
/* program is valid, convert *(u32*)(ctx + off) accesses */
ret = convert_ctx_accesses(env);
if (ret == 0)
ret = fixup_bpf_calls(env);
+ if (ret == 0)
+ ret = fixup_call_args(env);
+
if (log->level && bpf_verifier_log_full(log))
ret = -ENOSPC;
if (log->level && !log->ubuf) {
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d0d9bfb47d2e..f0549e79978b 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4732,6 +4732,9 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon
rcu_read_unlock();
return 0;
}
+
+ case PERF_EVENT_IOC_QUERY_BPF:
+ return perf_event_query_prog_array(event, (void __user *)arg);
default:
return -ENOTTY;
}
@@ -8100,6 +8103,13 @@ static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd)
return -EINVAL;
}
+ /* Kprobe override only works for kprobes, not uprobes. */
+ if (prog->kprobe_override &&
+ !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) {
+ bpf_prog_put(prog);
+ return -EINVAL;
+ }
+
if (is_tracepoint || is_syscall_tp) {
int off = trace_event_get_offsets(event->tp_event);
diff --git a/kernel/fail_function.c b/kernel/fail_function.c
new file mode 100644
index 000000000000..21b0122cb39c
--- /dev/null
+++ b/kernel/fail_function.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * fail_function.c: Function-based error injection
+ */
+#include <linux/error-injection.h>
+#include <linux/debugfs.h>
+#include <linux/fault-inject.h>
+#include <linux/kallsyms.h>
+#include <linux/kprobes.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs);
+
+struct fei_attr {
+ struct list_head list;
+ struct kprobe kp;
+ unsigned long retval;
+};
+static DEFINE_MUTEX(fei_lock);
+static LIST_HEAD(fei_attr_list);
+static DECLARE_FAULT_ATTR(fei_fault_attr);
+static struct dentry *fei_debugfs_dir;
+
+static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
+{
+ switch (get_injectable_error_type(addr)) {
+ case EI_ETYPE_NULL:
+ if (retv != 0)
+ return 0;
+ break;
+ case EI_ETYPE_ERRNO:
+ if (retv < (unsigned long)-MAX_ERRNO)
+ return (unsigned long)-EINVAL;
+ break;
+ case EI_ETYPE_ERRNO_NULL:
+ if (retv != 0 && retv < (unsigned long)-MAX_ERRNO)
+ return (unsigned long)-EINVAL;
+ break;
+ }
+
+ return retv;
+}
+
+static struct fei_attr *fei_attr_new(const char *sym, unsigned long addr)
+{
+ struct fei_attr *attr;
+
+ attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+ if (attr) {
+ attr->kp.symbol_name = kstrdup(sym, GFP_KERNEL);
+ if (!attr->kp.symbol_name) {
+ kfree(attr);
+ return NULL;
+ }
+ attr->kp.pre_handler = fei_kprobe_handler;
+ attr->retval = adjust_error_retval(addr, 0);
+ INIT_LIST_HEAD(&attr->list);
+ }
+ return attr;
+}
+
+static void fei_attr_free(struct fei_attr *attr)
+{
+ if (attr) {
+ kfree(attr->kp.symbol_name);
+ kfree(attr);
+ }
+}
+
+static struct fei_attr *fei_attr_lookup(const char *sym)
+{
+ struct fei_attr *attr;
+
+ list_for_each_entry(attr, &fei_attr_list, list) {
+ if (!strcmp(attr->kp.symbol_name, sym))
+ return attr;
+ }
+
+ return NULL;
+}
+
+static bool fei_attr_is_valid(struct fei_attr *_attr)
+{
+ struct fei_attr *attr;
+
+ list_for_each_entry(attr, &fei_attr_list, list) {
+ if (attr == _attr)
+ return true;
+ }
+
+ return false;
+}
+
+static int fei_retval_set(void *data, u64 val)
+{
+ struct fei_attr *attr = data;
+ unsigned long retv = (unsigned long)val;
+ int err = 0;
+
+ mutex_lock(&fei_lock);
+ /*
+ * Since this operation can be done after retval file is removed,
+ * It is safer to check the attr is still valid before accessing
+ * its member.
+ */
+ if (!fei_attr_is_valid(attr)) {
+ err = -ENOENT;
+ goto out;
+ }
+
+ if (attr->kp.addr) {
+ if (adjust_error_retval((unsigned long)attr->kp.addr,
+ val) != retv)
+ err = -EINVAL;
+ }
+ if (!err)
+ attr->retval = val;
+out:
+ mutex_unlock(&fei_lock);
+
+ return err;
+}
+
+static int fei_retval_get(void *data, u64 *val)
+{
+ struct fei_attr *attr = data;
+ int err = 0;
+
+ mutex_lock(&fei_lock);
+ /* Here we also validate @attr to ensure it still exists. */
+ if (!fei_attr_is_valid(attr))
+ err = -ENOENT;
+ else
+ *val = attr->retval;
+ mutex_unlock(&fei_lock);
+
+ return err;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fei_retval_ops, fei_retval_get, fei_retval_set,
+ "%llx\n");
+
+static int fei_debugfs_add_attr(struct fei_attr *attr)
+{
+ struct dentry *dir;
+
+ dir = debugfs_create_dir(attr->kp.symbol_name, fei_debugfs_dir);
+ if (!dir)
+ return -ENOMEM;
+
+ if (!debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops)) {
+ debugfs_remove_recursive(dir);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void fei_debugfs_remove_attr(struct fei_attr *attr)
+{
+ struct dentry *dir;
+
+ dir = debugfs_lookup(attr->kp.symbol_name, fei_debugfs_dir);
+ if (dir)
+ debugfs_remove_recursive(dir);
+}
+
+static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs)
+{
+ struct fei_attr *attr = container_of(kp, struct fei_attr, kp);
+
+ if (should_fail(&fei_fault_attr, 1)) {
+ regs_set_return_value(regs, attr->retval);
+ override_function_with_return(regs);
+ /* Kprobe specific fixup */
+ reset_current_kprobe();
+ preempt_enable_no_resched();
+ return 1;
+ }
+
+ return 0;
+}
+NOKPROBE_SYMBOL(fei_kprobe_handler)
+
+static void *fei_seq_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&fei_lock);
+ return seq_list_start(&fei_attr_list, *pos);
+}
+
+static void fei_seq_stop(struct seq_file *m, void *v)
+{
+ mutex_unlock(&fei_lock);
+}
+
+static void *fei_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &fei_attr_list, pos);
+}
+
+static int fei_seq_show(struct seq_file *m, void *v)
+{
+ struct fei_attr *attr = list_entry(v, struct fei_attr, list);
+
+ seq_printf(m, "%pf\n", attr->kp.addr);
+ return 0;
+}
+
+static const struct seq_operations fei_seq_ops = {
+ .start = fei_seq_start,
+ .next = fei_seq_next,
+ .stop = fei_seq_stop,
+ .show = fei_seq_show,
+};
+
+static int fei_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &fei_seq_ops);
+}
+
+static void fei_attr_remove(struct fei_attr *attr)
+{
+ fei_debugfs_remove_attr(attr);
+ unregister_kprobe(&attr->kp);
+ list_del(&attr->list);
+ fei_attr_free(attr);
+}
+
+static void fei_attr_remove_all(void)
+{
+ struct fei_attr *attr, *n;
+
+ list_for_each_entry_safe(attr, n, &fei_attr_list, list) {
+ fei_attr_remove(attr);
+ }
+}
+
+static ssize_t fei_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct fei_attr *attr;
+ unsigned long addr;
+ char *buf, *sym;
+ int ret;
+
+ /* cut off if it is too long */
+ if (count > KSYM_NAME_LEN)
+ count = KSYM_NAME_LEN;
+ buf = kmalloc(sizeof(char) * (count + 1), GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ if (copy_from_user(buf, buffer, count)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ buf[count] = '\0';
+ sym = strstrip(buf);
+
+ mutex_lock(&fei_lock);
+
+ /* Writing just spaces will remove all injection points */
+ if (sym[0] == '\0') {
+ fei_attr_remove_all();
+ ret = count;
+ goto out;
+ }
+ /* Writing !function will remove one injection point */
+ if (sym[0] == '!') {
+ attr = fei_attr_lookup(sym + 1);
+ if (!attr) {
+ ret = -ENOENT;
+ goto out;
+ }
+ fei_attr_remove(attr);
+ ret = count;
+ goto out;
+ }
+
+ addr = kallsyms_lookup_name(sym);
+ if (!addr) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!within_error_injection_list(addr)) {
+ ret = -ERANGE;
+ goto out;
+ }
+ if (fei_attr_lookup(sym)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ attr = fei_attr_new(sym, addr);
+ if (!attr) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = register_kprobe(&attr->kp);
+ if (!ret)
+ ret = fei_debugfs_add_attr(attr);
+ if (ret < 0)
+ fei_attr_remove(attr);
+ else {
+ list_add_tail(&attr->list, &fei_attr_list);
+ ret = count;
+ }
+out:
+ kfree(buf);
+ mutex_unlock(&fei_lock);
+ return ret;
+}
+
+static const struct file_operations fei_ops = {
+ .open = fei_open,
+ .read = seq_read,
+ .write = fei_write,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init fei_debugfs_init(void)
+{
+ struct dentry *dir;
+
+ dir = fault_create_debugfs_attr("fail_function", NULL,
+ &fei_fault_attr);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ /* injectable attribute is just a symlink of error_inject/list */
+ if (!debugfs_create_symlink("injectable", dir,
+ "../error_injection/list"))
+ goto error;
+
+ if (!debugfs_create_file("inject", 0600, dir, NULL, &fei_ops))
+ goto error;
+
+ fei_debugfs_dir = dir;
+
+ return 0;
+error:
+ debugfs_remove_recursive(dir);
+ return -ENOMEM;
+}
+
+late_initcall(fei_debugfs_init);
diff --git a/kernel/module.c b/kernel/module.c
index 09e48eee4d55..1d65b2cc4f80 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3129,7 +3129,11 @@ static int find_module_sections(struct module *mod, struct load_info *info)
sizeof(*mod->ftrace_callsites),
&mod->num_ftrace_callsites);
#endif
-
+#ifdef CONFIG_FUNCTION_ERROR_INJECTION
+ mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
+ sizeof(*mod->ei_funcs),
+ &mod->num_ei_funcs);
+#endif
mod->extable = section_objs(info, "__ex_table",
sizeof(*mod->extable), &mod->num_exentries);
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index f54dc62b599c..0b249e2f0c3c 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -530,6 +530,15 @@ config FUNCTION_PROFILER
If in doubt, say N.
+config BPF_KPROBE_OVERRIDE
+ bool "Enable BPF programs to override a kprobed function"
+ depends on BPF_EVENTS
+ depends on FUNCTION_ERROR_INJECTION
+ default n
+ help
+ Allows BPF to override the execution of a probed function and
+ set a different return value. This is used for error injection.
+
config FTRACE_MCOUNT_RECORD
def_bool y
depends on DYNAMIC_FTRACE
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 40207c2a4113..fc2838ac8b78 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -13,6 +13,10 @@
#include <linux/filter.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
+#include <linux/kprobes.h>
+#include <linux/error-injection.h>
+
+#include "trace_probe.h"
#include "trace.h"
u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
@@ -76,6 +80,23 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
}
EXPORT_SYMBOL_GPL(trace_call_bpf);
+#ifdef CONFIG_BPF_KPROBE_OVERRIDE
+BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
+{
+ regs_set_return_value(regs, rc);
+ override_function_with_return(regs);
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_override_return_proto = {
+ .func = bpf_override_return,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+};
+#endif
+
BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
{
int ret;
@@ -224,7 +245,7 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
*/
#define __BPF_TP_EMIT() __BPF_ARG3_TP()
#define __BPF_TP(...) \
- __trace_printk(1 /* Fake ip will not be printed. */, \
+ __trace_printk(0 /* Fake ip */, \
fmt, ##__VA_ARGS__)
#define __BPF_ARG1_TP(...) \
@@ -556,6 +577,10 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func
return &bpf_get_stackid_proto;
case BPF_FUNC_perf_event_read_value:
return &bpf_perf_event_read_value_proto;
+#ifdef CONFIG_BPF_KPROBE_OVERRIDE
+ case BPF_FUNC_override_return:
+ return &bpf_override_return_proto;
+#endif
default:
return tracing_func_proto(func_id);
}
@@ -773,6 +798,15 @@ int perf_event_attach_bpf_prog(struct perf_event *event,
struct bpf_prog_array *new_array;
int ret = -EEXIST;
+ /*
+ * Kprobe override only works if they are on the function entry,
+ * and only if they are on the opt-in list.
+ */
+ if (prog->kprobe_override &&
+ (!trace_kprobe_on_func_entry(event->tp_event) ||
+ !trace_kprobe_error_injectable(event->tp_event)))
+ return -EINVAL;
+
mutex_lock(&bpf_event_mutex);
if (event->prog)
@@ -825,3 +859,26 @@ void perf_event_detach_bpf_prog(struct perf_event *event)
unlock:
mutex_unlock(&bpf_event_mutex);
}
+
+int perf_event_query_prog_array(struct perf_event *event, void __user *info)
+{
+ struct perf_event_query_bpf __user *uquery = info;
+ struct perf_event_query_bpf query = {};
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ if (event->attr.type != PERF_TYPE_TRACEPOINT)
+ return -EINVAL;
+ if (copy_from_user(&query, uquery, sizeof(query)))
+ return -EFAULT;
+
+ mutex_lock(&bpf_event_mutex);
+ ret = bpf_prog_array_copy_info(event->tp_event->prog_array,
+ uquery->ids,
+ query.ids_len,
+ &uquery->prog_cnt);
+ mutex_unlock(&bpf_event_mutex);
+
+ return ret;
+}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 492700c5fb4d..1fad24acd444 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -21,6 +21,7 @@
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/rculist.h>
+#include <linux/error-injection.h>
#include "trace_probe.h"
@@ -42,7 +43,6 @@ struct trace_kprobe {
(offsetof(struct trace_kprobe, tp.args) + \
(sizeof(struct probe_arg) * (n)))
-
static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
{
return tk->rp.handler != NULL;
@@ -87,6 +87,30 @@ static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
return nhit;
}
+bool trace_kprobe_on_func_entry(struct trace_event_call *call)
+{
+ struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+
+ return kprobe_on_func_entry(tk->rp.kp.addr,
+ tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name,
+ tk->rp.kp.addr ? 0 : tk->rp.kp.offset);
+}
+
+bool trace_kprobe_error_injectable(struct trace_event_call *call)
+{
+ struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
+ unsigned long addr;
+
+ if (tk->symbol) {
+ addr = (unsigned long)
+ kallsyms_lookup_name(trace_kprobe_symbol(tk));
+ addr += tk->rp.kp.offset;
+ } else {
+ addr = (unsigned long)tk->rp.kp.addr;
+ }
+ return within_error_injection_list(addr);
+}
+
static int register_kprobe_event(struct trace_kprobe *tk);
static int unregister_kprobe_event(struct trace_kprobe *tk);
@@ -1170,7 +1194,7 @@ static int kretprobe_event_define_fields(struct trace_event_call *event_call)
#ifdef CONFIG_PERF_EVENTS
/* Kprobe profile handler */
-static void
+static int
kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
{
struct trace_event_call *call = &tk->tp.call;
@@ -1179,12 +1203,31 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
int size, __size, dsize;
int rctx;
- if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs))
- return;
+ if (bpf_prog_array_valid(call)) {
+ unsigned long orig_ip = instruction_pointer(regs);
+ int ret;
+
+ ret = trace_call_bpf(call, regs);
+
+ /*
+ * We need to check and see if we modified the pc of the
+ * pt_regs, and if so clear the kprobe and return 1 so that we
+ * don't do the single stepping.
+ * The ftrace kprobe handler leaves it up to us to re-enable
+ * preemption here before returning if we've modified the ip.
+ */
+ if (orig_ip != instruction_pointer(regs)) {
+ reset_current_kprobe();
+ preempt_enable_no_resched();
+ return 1;
+ }
+ if (!ret)
+ return 0;
+ }
head = this_cpu_ptr(call->perf_events);
if (hlist_empty(head))
- return;
+ return 0;
dsize = __get_data_size(&tk->tp, regs);
__size = sizeof(*entry) + tk->tp.size + dsize;
@@ -1193,13 +1236,14 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs)
entry = perf_trace_buf_alloc(size, NULL, &rctx);
if (!entry)
- return;
+ return 0;
entry->ip = (unsigned long)tk->rp.kp.addr;
memset(&entry[1], 0, dsize);
store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize);
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
head, NULL);
+ return 0;
}
NOKPROBE_SYMBOL(kprobe_perf_func);
@@ -1275,6 +1319,7 @@ static int kprobe_register(struct trace_event_call *event,
static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
{
struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp);
+ int ret = 0;
raw_cpu_inc(*tk->nhit);
@@ -1282,9 +1327,9 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
kprobe_trace_func(tk, regs);
#ifdef CONFIG_PERF_EVENTS
if (tk->tp.flags & TP_FLAG_PROFILE)
- kprobe_perf_func(tk, regs);
+ ret = kprobe_perf_func(tk, regs);
#endif
- return 0; /* We don't tweek kernel, so just return 0 */
+ return ret;
}
NOKPROBE_SYMBOL(kprobe_dispatcher);
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index fb66e3eaa192..e101c5bb9eda 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -252,6 +252,8 @@ struct symbol_cache;
unsigned long update_symbol_cache(struct symbol_cache *sc);
void free_symbol_cache(struct symbol_cache *sc);
struct symbol_cache *alloc_symbol_cache(const char *sym, long offset);
+bool trace_kprobe_on_func_entry(struct trace_event_call *call);
+bool trace_kprobe_error_injectable(struct trace_event_call *call);
#else
/* uprobes do not support symbol fetch methods */
#define fetch_symbol_u8 NULL
@@ -277,6 +279,16 @@ alloc_symbol_cache(const char *sym, long offset)
{
return NULL;
}
+
+static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call)
+{
+ return false;
+}
+
+static inline bool trace_kprobe_error_injectable(struct trace_event_call *call)
+{
+ return false;
+}
#endif /* CONFIG_KPROBE_EVENTS */
struct probe_arg {