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-rw-r--r--kernel/bpf/core.c258
-rw-r--r--kernel/bpf/lpm_trie.c28
-rw-r--r--kernel/bpf/syscall.c5
-rw-r--r--kernel/bpf/verifier.c62
4 files changed, 207 insertions, 146 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 3aa0658add76..5f35f93dcab2 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -782,6 +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
@@ -793,115 +924,18 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
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;
@@ -965,14 +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;
@@ -985,13 +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;
@@ -1302,8 +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 */
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index d7ea96218516..7b469d10d0e9 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -593,11 +593,10 @@ unlock:
static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
{
+ 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, *next_node = NULL, *parent;
struct lpm_trie_node **node_stack = NULL;
- struct lpm_trie_node __rcu **root;
int err = 0, stack_ptr = -1;
unsigned int next_bit;
size_t matchlen;
@@ -614,22 +613,21 @@ static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
*/
/* Empty trie */
- if (!rcu_dereference(trie->root))
+ 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) {
- root = &trie->root;
+ if (!key || key->prefixlen > trie->max_prefixlen)
goto find_leftmost;
- }
node_stack = kmalloc(trie->max_prefixlen * sizeof(struct lpm_trie_node *),
- GFP_USER | __GFP_NOWARN);
+ GFP_ATOMIC | __GFP_NOWARN);
if (!node_stack)
return -ENOMEM;
/* Try to find the exact node for the given key */
- for (node = rcu_dereference(trie->root); node;) {
+ for (node = search_root; node;) {
node_stack[++stack_ptr] = node;
matchlen = longest_prefix_match(trie, node, key);
if (node->prefixlen != matchlen ||
@@ -640,10 +638,8 @@ static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
node = rcu_dereference(node->child[next_bit]);
}
if (!node || node->prefixlen != key->prefixlen ||
- (node->flags & LPM_TREE_NODE_FLAG_IM)) {
- root = &trie->root;
+ (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.
@@ -651,10 +647,10 @@ static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key)
node = node_stack[stack_ptr];
while (stack_ptr > 0) {
parent = node_stack[stack_ptr - 1];
- if (rcu_dereference(parent->child[0]) == node &&
- rcu_dereference(parent->child[1])) {
- root = &parent->child[1];
- goto find_leftmost;
+ 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;
@@ -673,7 +669,7 @@ find_leftmost:
/* Find the leftmost non-intermediate node, all intermediate nodes
* have exact two children, so this function will never return NULL.
*/
- for (node = rcu_dereference(*root); node;) {
+ for (node = search_root; node;) {
if (!(node->flags & LPM_TREE_NODE_FLAG_IM))
next_node = node;
node = rcu_dereference(node->child[0]);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5bdb0cc84ad2..e24aa3241387 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -709,10 +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);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index dfb138b46488..5fb69a85d967 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4981,6 +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;
}
}
@@ -5064,14 +5071,21 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of
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;
@@ -5079,7 +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));
}
}
@@ -5386,15 +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;
generated by cgit (git 2.34.1) at 2024-05-28 05:25:50 +0000