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authorJakub Kicinski <kuba@kernel.org>2024-03-11 18:06:04 -0700
committerJakub Kicinski <kuba@kernel.org>2024-03-11 18:06:04 -0700
commit5f20e6ab1f65aaaaae248e6946d5cb6d039e7de8 (patch)
tree826f8a879f1d954b00e4b07a8afe271aed02992e /kernel/bpf/verifier.c
parentf095fefacdd35b4ea97dc6d88d054f2749a73d07 (diff)
parent66c8473135c62f478301a0e5b3012f203562dfa6 (diff)
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== pull-request: bpf-next 2024-03-11 We've added 59 non-merge commits during the last 9 day(s) which contain a total of 88 files changed, 4181 insertions(+), 590 deletions(-). The main changes are: 1) Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce VM_SPARSE kind and vm_area_[un]map_pages to be used in bpf_arena, from Alexei. 2) Introduce bpf_arena which is sparse shared memory region between bpf program and user space where structures inside the arena can have pointers to other areas of the arena, and pointers work seamlessly for both user-space programs and bpf programs, from Alexei and Andrii. 3) Introduce may_goto instruction that is a contract between the verifier and the program. The verifier allows the program to loop assuming it's behaving well, but reserves the right to terminate it, from Alexei. 4) Use IETF format for field definitions in the BPF standard document, from Dave. 5) Extend struct_ops libbpf APIs to allow specify version suffixes for stuct_ops map types, share the same BPF program between several map definitions, and other improvements, from Eduard. 6) Enable struct_ops support for more than one page in trampolines, from Kui-Feng. 7) Support kCFI + BPF on riscv64, from Puranjay. 8) Use bpf_prog_pack for arm64 bpf trampoline, from Puranjay. 9) Fix roundup_pow_of_two undefined behavior on 32-bit archs, from Toke. ==================== Link: https://lore.kernel.org/r/20240312003646.8692-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r--kernel/bpf/verifier.c366
1 files changed, 301 insertions, 65 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 21f80383f8b2..63749ad5ac6b 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -533,6 +533,16 @@ static bool is_async_callback_calling_insn(struct bpf_insn *insn)
return bpf_helper_call(insn) && is_async_callback_calling_function(insn->imm);
}
+static bool is_may_goto_insn(struct bpf_insn *insn)
+{
+ return insn->code == (BPF_JMP | BPF_JCOND) && insn->src_reg == BPF_MAY_GOTO;
+}
+
+static bool is_may_goto_insn_at(struct bpf_verifier_env *env, int insn_idx)
+{
+ return is_may_goto_insn(&env->prog->insnsi[insn_idx]);
+}
+
static bool is_storage_get_function(enum bpf_func_id func_id)
{
return func_id == BPF_FUNC_sk_storage_get ||
@@ -1429,6 +1439,7 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state,
dst_state->dfs_depth = src->dfs_depth;
dst_state->callback_unroll_depth = src->callback_unroll_depth;
dst_state->used_as_loop_entry = src->used_as_loop_entry;
+ dst_state->may_goto_depth = src->may_goto_depth;
for (i = 0; i <= src->curframe; i++) {
dst = dst_state->frame[i];
if (!dst) {
@@ -4375,6 +4386,7 @@ static bool is_spillable_regtype(enum bpf_reg_type type)
case PTR_TO_MEM:
case PTR_TO_FUNC:
case PTR_TO_MAP_KEY:
+ case PTR_TO_ARENA:
return true;
default:
return false;
@@ -5262,7 +5274,7 @@ bad_type:
static bool in_sleepable(struct bpf_verifier_env *env)
{
- return env->prog->aux->sleepable;
+ return env->prog->sleepable;
}
/* The non-sleepable programs and sleepable programs with explicit bpf_rcu_read_lock()
@@ -5817,6 +5829,8 @@ static int check_ptr_alignment(struct bpf_verifier_env *env,
case PTR_TO_XDP_SOCK:
pointer_desc = "xdp_sock ";
break;
+ case PTR_TO_ARENA:
+ return 0;
default:
break;
}
@@ -6926,6 +6940,9 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
if (!err && value_regno >= 0 && (rdonly_mem || t == BPF_READ))
mark_reg_unknown(env, regs, value_regno);
+ } else if (reg->type == PTR_TO_ARENA) {
+ if (t == BPF_READ && value_regno >= 0)
+ mark_reg_unknown(env, regs, value_regno);
} else {
verbose(env, "R%d invalid mem access '%s'\n", regno,
reg_type_str(env, reg->type));
@@ -8397,6 +8414,7 @@ static int check_func_arg_reg_off(struct bpf_verifier_env *env,
case PTR_TO_MEM | MEM_RINGBUF:
case PTR_TO_BUF:
case PTR_TO_BUF | MEM_RDONLY:
+ case PTR_TO_ARENA:
case SCALAR_VALUE:
return 0;
/* All the rest must be rejected, except PTR_TO_BTF_ID which allows
@@ -9361,6 +9379,18 @@ static int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
bpf_log(log, "arg#%d is expected to be non-NULL\n", i);
return -EINVAL;
}
+ } else if (base_type(arg->arg_type) == ARG_PTR_TO_ARENA) {
+ /*
+ * Can pass any value and the kernel won't crash, but
+ * only PTR_TO_ARENA or SCALAR make sense. Everything
+ * else is a bug in the bpf program. Point it out to
+ * the user at the verification time instead of
+ * run-time debug nightmare.
+ */
+ if (reg->type != PTR_TO_ARENA && reg->type != SCALAR_VALUE) {
+ bpf_log(log, "R%d is not a pointer to arena or scalar.\n", regno);
+ return -EINVAL;
+ }
} else if (arg->arg_type == (ARG_PTR_TO_DYNPTR | MEM_RDONLY)) {
ret = process_dynptr_func(env, regno, -1, arg->arg_type, 0);
if (ret)
@@ -10741,6 +10771,11 @@ static bool is_kfunc_arg_ignore(const struct btf *btf, const struct btf_param *a
return btf_param_match_suffix(btf, arg, "__ign");
}
+static bool is_kfunc_arg_map(const struct btf *btf, const struct btf_param *arg)
+{
+ return btf_param_match_suffix(btf, arg, "__map");
+}
+
static bool is_kfunc_arg_alloc_obj(const struct btf *btf, const struct btf_param *arg)
{
return btf_param_match_suffix(btf, arg, "__alloc");
@@ -10910,6 +10945,7 @@ enum kfunc_ptr_arg_type {
KF_ARG_PTR_TO_RB_NODE,
KF_ARG_PTR_TO_NULL,
KF_ARG_PTR_TO_CONST_STR,
+ KF_ARG_PTR_TO_MAP,
};
enum special_kfunc_type {
@@ -11063,6 +11099,9 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
if (is_kfunc_arg_const_str(meta->btf, &args[argno]))
return KF_ARG_PTR_TO_CONST_STR;
+ if (is_kfunc_arg_map(meta->btf, &args[argno]))
+ return KF_ARG_PTR_TO_MAP;
+
if ((base_type(reg->type) == PTR_TO_BTF_ID || reg2btf_ids[base_type(reg->type)])) {
if (!btf_type_is_struct(ref_t)) {
verbose(env, "kernel function %s args#%d pointer type %s %s is not supported\n",
@@ -11663,6 +11702,7 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_
switch (kf_arg_type) {
case KF_ARG_PTR_TO_NULL:
continue;
+ case KF_ARG_PTR_TO_MAP:
case KF_ARG_PTR_TO_ALLOC_BTF_ID:
case KF_ARG_PTR_TO_BTF_ID:
if (!is_kfunc_trusted_args(meta) && !is_kfunc_rcu(meta))
@@ -11879,6 +11919,12 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_
if (ret < 0)
return ret;
break;
+ case KF_ARG_PTR_TO_MAP:
+ /* If argument has '__map' suffix expect 'struct bpf_map *' */
+ ref_id = *reg2btf_ids[CONST_PTR_TO_MAP];
+ ref_t = btf_type_by_id(btf_vmlinux, ref_id);
+ ref_tname = btf_name_by_offset(btf, ref_t->name_off);
+ fallthrough;
case KF_ARG_PTR_TO_BTF_ID:
/* Only base_type is checked, further checks are done here */
if ((base_type(reg->type) != PTR_TO_BTF_ID ||
@@ -12353,6 +12399,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
meta.func_name);
return -EFAULT;
}
+ } else if (btf_type_is_void(ptr_type)) {
+ /* kfunc returning 'void *' is equivalent to returning scalar */
+ mark_reg_unknown(env, regs, BPF_REG_0);
} else if (!__btf_type_is_struct(ptr_type)) {
if (!meta.r0_size) {
__u32 sz;
@@ -13822,6 +13871,21 @@ static int adjust_reg_min_max_vals(struct bpf_verifier_env *env,
dst_reg = &regs[insn->dst_reg];
src_reg = NULL;
+
+ if (dst_reg->type == PTR_TO_ARENA) {
+ struct bpf_insn_aux_data *aux = cur_aux(env);
+
+ if (BPF_CLASS(insn->code) == BPF_ALU64)
+ /*
+ * 32-bit operations zero upper bits automatically.
+ * 64-bit operations need to be converted to 32.
+ */
+ aux->needs_zext = true;
+
+ /* Any arithmetic operations are allowed on arena pointers */
+ return 0;
+ }
+
if (dst_reg->type != SCALAR_VALUE)
ptr_reg = dst_reg;
else
@@ -13939,19 +14003,20 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
} else if (opcode == BPF_MOV) {
if (BPF_SRC(insn->code) == BPF_X) {
- if (insn->imm != 0) {
- verbose(env, "BPF_MOV uses reserved fields\n");
- return -EINVAL;
- }
-
if (BPF_CLASS(insn->code) == BPF_ALU) {
- if (insn->off != 0 && insn->off != 8 && insn->off != 16) {
+ if ((insn->off != 0 && insn->off != 8 && insn->off != 16) ||
+ insn->imm) {
verbose(env, "BPF_MOV uses reserved fields\n");
return -EINVAL;
}
+ } else if (insn->off == BPF_ADDR_SPACE_CAST) {
+ if (insn->imm != 1 && insn->imm != 1u << 16) {
+ verbose(env, "addr_space_cast insn can only convert between address space 1 and 0\n");
+ return -EINVAL;
+ }
} else {
- if (insn->off != 0 && insn->off != 8 && insn->off != 16 &&
- insn->off != 32) {
+ if ((insn->off != 0 && insn->off != 8 && insn->off != 16 &&
+ insn->off != 32) || insn->imm) {
verbose(env, "BPF_MOV uses reserved fields\n");
return -EINVAL;
}
@@ -13978,7 +14043,12 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
struct bpf_reg_state *dst_reg = regs + insn->dst_reg;
if (BPF_CLASS(insn->code) == BPF_ALU64) {
- if (insn->off == 0) {
+ if (insn->imm) {
+ /* off == BPF_ADDR_SPACE_CAST */
+ mark_reg_unknown(env, regs, insn->dst_reg);
+ if (insn->imm == 1) /* cast from as(1) to as(0) */
+ dst_reg->type = PTR_TO_ARENA;
+ } else if (insn->off == 0) {
/* case: R1 = R2
* copy register state to dest reg
*/
@@ -14871,11 +14941,36 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
int err;
/* Only conditional jumps are expected to reach here. */
- if (opcode == BPF_JA || opcode > BPF_JSLE) {
+ if (opcode == BPF_JA || opcode > BPF_JCOND) {
verbose(env, "invalid BPF_JMP/JMP32 opcode %x\n", opcode);
return -EINVAL;
}
+ if (opcode == BPF_JCOND) {
+ struct bpf_verifier_state *cur_st = env->cur_state, *queued_st, *prev_st;
+ int idx = *insn_idx;
+
+ if (insn->code != (BPF_JMP | BPF_JCOND) ||
+ insn->src_reg != BPF_MAY_GOTO ||
+ insn->dst_reg || insn->imm || insn->off == 0) {
+ verbose(env, "invalid may_goto off %d imm %d\n",
+ insn->off, insn->imm);
+ return -EINVAL;
+ }
+ prev_st = find_prev_entry(env, cur_st->parent, idx);
+
+ /* branch out 'fallthrough' insn as a new state to explore */
+ queued_st = push_stack(env, idx + 1, idx, false);
+ if (!queued_st)
+ return -ENOMEM;
+
+ queued_st->may_goto_depth++;
+ if (prev_st)
+ widen_imprecise_scalars(env, prev_st, queued_st);
+ *insn_idx += insn->off;
+ return 0;
+ }
+
/* check src2 operand */
err = check_reg_arg(env, insn->dst_reg, SRC_OP);
if (err)
@@ -15127,6 +15222,10 @@ static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
if (insn->src_reg == BPF_PSEUDO_MAP_VALUE ||
insn->src_reg == BPF_PSEUDO_MAP_IDX_VALUE) {
+ if (map->map_type == BPF_MAP_TYPE_ARENA) {
+ __mark_reg_unknown(env, dst_reg);
+ return 0;
+ }
dst_reg->type = PTR_TO_MAP_VALUE;
dst_reg->off = aux->map_off;
WARN_ON_ONCE(map->max_entries != 1);
@@ -15659,6 +15758,8 @@ static int visit_insn(int t, struct bpf_verifier_env *env)
default:
/* conditional jump with two edges */
mark_prune_point(env, t);
+ if (is_may_goto_insn(insn))
+ mark_force_checkpoint(env, t);
ret = push_insn(t, t + 1, FALLTHROUGH, env);
if (ret)
@@ -16222,8 +16323,8 @@ static int check_btf_info(struct bpf_verifier_env *env,
}
/* check %cur's range satisfies %old's */
-static bool range_within(struct bpf_reg_state *old,
- struct bpf_reg_state *cur)
+static bool range_within(const struct bpf_reg_state *old,
+ const struct bpf_reg_state *cur)
{
return old->umin_value <= cur->umin_value &&
old->umax_value >= cur->umax_value &&
@@ -16387,21 +16488,28 @@ static bool regs_exact(const struct bpf_reg_state *rold,
check_ids(rold->ref_obj_id, rcur->ref_obj_id, idmap);
}
+enum exact_level {
+ NOT_EXACT,
+ EXACT,
+ RANGE_WITHIN
+};
+
/* Returns true if (rold safe implies rcur safe) */
static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold,
- struct bpf_reg_state *rcur, struct bpf_idmap *idmap, bool exact)
+ struct bpf_reg_state *rcur, struct bpf_idmap *idmap,
+ enum exact_level exact)
{
- if (exact)
+ if (exact == EXACT)
return regs_exact(rold, rcur, idmap);
- if (!(rold->live & REG_LIVE_READ))
+ if (!(rold->live & REG_LIVE_READ) && exact == NOT_EXACT)
/* explored state didn't use this */
return true;
- if (rold->type == NOT_INIT)
- /* explored state can't have used this */
- return true;
- if (rcur->type == NOT_INIT)
- return false;
+ if (rold->type == NOT_INIT) {
+ if (exact == NOT_EXACT || rcur->type == NOT_INIT)
+ /* explored state can't have used this */
+ return true;
+ }
/* Enforce that register types have to match exactly, including their
* modifiers (like PTR_MAYBE_NULL, MEM_RDONLY, etc), as a general
@@ -16436,7 +16544,7 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold,
return memcmp(rold, rcur, offsetof(struct bpf_reg_state, id)) == 0 &&
check_scalar_ids(rold->id, rcur->id, idmap);
}
- if (!rold->precise)
+ if (!rold->precise && exact == NOT_EXACT)
return true;
/* Why check_ids() for scalar registers?
*
@@ -16504,6 +16612,8 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold,
* the same stack frame, since fp-8 in foo != fp-8 in bar
*/
return regs_exact(rold, rcur, idmap) && rold->frameno == rcur->frameno;
+ case PTR_TO_ARENA:
+ return true;
default:
return regs_exact(rold, rcur, idmap);
}
@@ -16547,7 +16657,8 @@ static struct bpf_reg_state *scalar_reg_for_stack(struct bpf_verifier_env *env,
}
static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old,
- struct bpf_func_state *cur, struct bpf_idmap *idmap, bool exact)
+ struct bpf_func_state *cur, struct bpf_idmap *idmap,
+ enum exact_level exact)
{
int i, spi;
@@ -16560,12 +16671,13 @@ static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old,
spi = i / BPF_REG_SIZE;
- if (exact &&
+ if (exact != NOT_EXACT &&
old->stack[spi].slot_type[i % BPF_REG_SIZE] !=
cur->stack[spi].slot_type[i % BPF_REG_SIZE])
return false;
- if (!(old->stack[spi].spilled_ptr.live & REG_LIVE_READ) && !exact) {
+ if (!(old->stack[spi].spilled_ptr.live & REG_LIVE_READ)
+ && exact == NOT_EXACT) {
i += BPF_REG_SIZE - 1;
/* explored state didn't use this */
continue;
@@ -16711,7 +16823,7 @@ static bool refsafe(struct bpf_func_state *old, struct bpf_func_state *cur,
* the current state will reach 'bpf_exit' instruction safely
*/
static bool func_states_equal(struct bpf_verifier_env *env, struct bpf_func_state *old,
- struct bpf_func_state *cur, bool exact)
+ struct bpf_func_state *cur, enum exact_level exact)
{
int i;
@@ -16741,7 +16853,7 @@ static void reset_idmap_scratch(struct bpf_verifier_env *env)
static bool states_equal(struct bpf_verifier_env *env,
struct bpf_verifier_state *old,
struct bpf_verifier_state *cur,
- bool exact)
+ enum exact_level exact)
{
int i;
@@ -17115,7 +17227,7 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
* => unsafe memory access at 11 would not be caught.
*/
if (is_iter_next_insn(env, insn_idx)) {
- if (states_equal(env, &sl->state, cur, true)) {
+ if (states_equal(env, &sl->state, cur, RANGE_WITHIN)) {
struct bpf_func_state *cur_frame;
struct bpf_reg_state *iter_state, *iter_reg;
int spi;
@@ -17138,15 +17250,23 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
}
goto skip_inf_loop_check;
}
+ if (is_may_goto_insn_at(env, insn_idx)) {
+ if (states_equal(env, &sl->state, cur, RANGE_WITHIN)) {
+ update_loop_entry(cur, &sl->state);
+ goto hit;
+ }
+ goto skip_inf_loop_check;
+ }
if (calls_callback(env, insn_idx)) {
- if (states_equal(env, &sl->state, cur, true))
+ if (states_equal(env, &sl->state, cur, RANGE_WITHIN))
goto hit;
goto skip_inf_loop_check;
}
/* attempt to detect infinite loop to avoid unnecessary doomed work */
if (states_maybe_looping(&sl->state, cur) &&
- states_equal(env, &sl->state, cur, true) &&
+ states_equal(env, &sl->state, cur, EXACT) &&
!iter_active_depths_differ(&sl->state, cur) &&
+ sl->state.may_goto_depth == cur->may_goto_depth &&
sl->state.callback_unroll_depth == cur->callback_unroll_depth) {
verbose_linfo(env, insn_idx, "; ");
verbose(env, "infinite loop detected at insn %d\n", insn_idx);
@@ -17202,7 +17322,7 @@ skip_inf_loop_check:
*/
loop_entry = get_loop_entry(&sl->state);
force_exact = loop_entry && loop_entry->branches > 0;
- if (states_equal(env, &sl->state, cur, force_exact)) {
+ if (states_equal(env, &sl->state, cur, force_exact ? RANGE_WITHIN : NOT_EXACT)) {
if (force_exact)
update_loop_entry(cur, loop_entry);
hit:
@@ -17372,6 +17492,7 @@ static bool reg_type_mismatch_ok(enum bpf_reg_type type)
case PTR_TO_TCP_SOCK:
case PTR_TO_XDP_SOCK:
case PTR_TO_BTF_ID:
+ case PTR_TO_ARENA:
return false;
default:
return true;
@@ -18019,7 +18140,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
return -EINVAL;
}
- if (prog->aux->sleepable)
+ if (prog->sleepable)
switch (map->map_type) {
case BPF_MAP_TYPE_HASH:
case BPF_MAP_TYPE_LRU_HASH:
@@ -18037,6 +18158,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
case BPF_MAP_TYPE_CGRP_STORAGE:
case BPF_MAP_TYPE_QUEUE:
case BPF_MAP_TYPE_STACK:
+ case BPF_MAP_TYPE_ARENA:
break;
default:
verbose(env,
@@ -18206,7 +18328,7 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env)
return -E2BIG;
}
- if (env->prog->aux->sleepable)
+ if (env->prog->sleepable)
atomic64_inc(&map->sleepable_refcnt);
/* hold the map. If the program is rejected by verifier,
* the map will be released by release_maps() or it
@@ -18224,6 +18346,31 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env)
fdput(f);
return -EBUSY;
}
+ if (map->map_type == BPF_MAP_TYPE_ARENA) {
+ if (env->prog->aux->arena) {
+ verbose(env, "Only one arena per program\n");
+ fdput(f);
+ return -EBUSY;
+ }
+ if (!env->allow_ptr_leaks || !env->bpf_capable) {
+ verbose(env, "CAP_BPF and CAP_PERFMON are required to use arena\n");
+ fdput(f);
+ return -EPERM;
+ }
+ if (!env->prog->jit_requested) {
+ verbose(env, "JIT is required to use arena\n");
+ return -EOPNOTSUPP;
+ }
+ if (!bpf_jit_supports_arena()) {
+ verbose(env, "JIT doesn't support arena\n");
+ return -EOPNOTSUPP;
+ }
+ env->prog->aux->arena = (void *)map;
+ if (!bpf_arena_get_user_vm_start(env->prog->aux->arena)) {
+ verbose(env, "arena's user address must be set via map_extra or mmap()\n");
+ return -EINVAL;
+ }
+ }
fdput(f);
next_insn:
@@ -18845,6 +18992,14 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
env->prog->aux->num_exentries++;
}
continue;
+ case PTR_TO_ARENA:
+ if (BPF_MODE(insn->code) == BPF_MEMSX) {
+ verbose(env, "sign extending loads from arena are not supported yet\n");
+ return -EOPNOTSUPP;
+ }
+ insn->code = BPF_CLASS(insn->code) | BPF_PROBE_MEM32 | BPF_SIZE(insn->code);
+ env->prog->aux->num_exentries++;
+ continue;
default:
continue;
}
@@ -19030,13 +19185,19 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->nr_linfo = prog->aux->nr_linfo;
func[i]->aux->jited_linfo = prog->aux->jited_linfo;
func[i]->aux->linfo_idx = env->subprog_info[i].linfo_idx;
+ func[i]->aux->arena = prog->aux->arena;
num_exentries = 0;
insn = func[i]->insnsi;
for (j = 0; j < func[i]->len; j++, insn++) {
if (BPF_CLASS(insn->code) == BPF_LDX &&
(BPF_MODE(insn->code) == BPF_PROBE_MEM ||
+ BPF_MODE(insn->code) == BPF_PROBE_MEM32 ||
BPF_MODE(insn->code) == BPF_PROBE_MEMSX))
num_exentries++;
+ if ((BPF_CLASS(insn->code) == BPF_STX ||
+ BPF_CLASS(insn->code) == BPF_ST) &&
+ BPF_MODE(insn->code) == BPF_PROBE_MEM32)
+ num_exentries++;
}
func[i]->aux->num_exentries = num_exentries;
func[i]->aux->tail_call_reachable = env->subprog_info[i].tail_call_reachable;
@@ -19411,7 +19572,10 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
struct bpf_insn insn_buf[16];
struct bpf_prog *new_prog;
struct bpf_map *map_ptr;
- int i, ret, cnt, delta = 0;
+ int i, ret, cnt, delta = 0, cur_subprog = 0;
+ struct bpf_subprog_info *subprogs = env->subprog_info;
+ u16 stack_depth = subprogs[cur_subprog].stack_depth;
+ u16 stack_depth_extra = 0;
if (env->seen_exception && !env->exception_callback_subprog) {
struct bpf_insn patch[] = {
@@ -19431,7 +19595,22 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
mark_subprog_exc_cb(env, env->exception_callback_subprog);
}
- for (i = 0; i < insn_cnt; i++, insn++) {
+ for (i = 0; i < insn_cnt;) {
+ if (insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && insn->imm) {
+ if ((insn->off == BPF_ADDR_SPACE_CAST && insn->imm == 1) ||
+ (((struct bpf_map *)env->prog->aux->arena)->map_flags & BPF_F_NO_USER_CONV)) {
+ /* convert to 32-bit mov that clears upper 32-bit */
+ insn->code = BPF_ALU | BPF_MOV | BPF_X;
+ /* clear off, so it's a normal 'wX = wY' from JIT pov */
+ insn->off = 0;
+ } /* cast from as(0) to as(1) should be handled by JIT */
+ goto next_insn;
+ }
+
+ if (env->insn_aux_data[i + delta].needs_zext)
+ /* Convert BPF_CLASS(insn->code) == BPF_ALU64 to 32-bit ALU */
+ insn->code = BPF_ALU | BPF_OP(insn->code) | BPF_SRC(insn->code);
+
/* Make divide-by-zero exceptions impossible. */
if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) ||
insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
@@ -19470,7 +19649,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement LD_ABS and LD_IND with a rewrite, if supported by the program type. */
@@ -19490,7 +19669,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Rewrite pointer arithmetic to mitigate speculation attacks. */
@@ -19505,7 +19684,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
aux = &env->insn_aux_data[i + delta];
if (!aux->alu_state ||
aux->alu_state == BPF_ALU_NON_POINTER)
- continue;
+ goto next_insn;
isneg = aux->alu_state & BPF_ALU_NEG_VALUE;
issrc = (aux->alu_state & BPF_ALU_SANITIZE) ==
@@ -19543,19 +19722,39 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
+ }
+
+ if (is_may_goto_insn(insn)) {
+ int stack_off = -stack_depth - 8;
+
+ stack_depth_extra = 8;
+ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_AX, BPF_REG_10, stack_off);
+ insn_buf[1] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_AX, 0, insn->off + 2);
+ insn_buf[2] = BPF_ALU64_IMM(BPF_SUB, BPF_REG_AX, 1);
+ insn_buf[3] = BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_AX, stack_off);
+ cnt = 4;
+
+ new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
+ if (!new_prog)
+ return -ENOMEM;
+
+ delta += cnt - 1;
+ env->prog = prog = new_prog;
+ insn = new_prog->insnsi + i + delta;
+ goto next_insn;
}
if (insn->code != (BPF_JMP | BPF_CALL))
- continue;
+ goto next_insn;
if (insn->src_reg == BPF_PSEUDO_CALL)
- continue;
+ goto next_insn;
if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) {
ret = fixup_kfunc_call(env, insn, insn_buf, i + delta, &cnt);
if (ret)
return ret;
if (cnt == 0)
- continue;
+ goto next_insn;
new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
if (!new_prog)
@@ -19564,7 +19763,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
if (insn->imm == BPF_FUNC_get_route_realm)
@@ -19612,11 +19811,11 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
}
insn->imm = ret + 1;
- continue;
+ goto next_insn;
}
if (!bpf_map_ptr_unpriv(aux))
- continue;
+ goto next_insn;
/* instead of changing every JIT dealing with tail_call
* emit two extra insns:
@@ -19645,7 +19844,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
if (insn->imm == BPF_FUNC_timer_set_callback) {
@@ -19757,7 +19956,7 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
BUILD_BUG_ON(!__same_type(ops->map_lookup_elem,
@@ -19788,31 +19987,31 @@ patch_map_ops_generic:
switch (insn->imm) {
case BPF_FUNC_map_lookup_elem:
insn->imm = BPF_CALL_IMM(ops->map_lookup_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_map_update_elem:
insn->imm = BPF_CALL_IMM(ops->map_update_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_map_delete_elem:
insn->imm = BPF_CALL_IMM(ops->map_delete_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_map_push_elem:
insn->imm = BPF_CALL_IMM(ops->map_push_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_map_pop_elem:
insn->imm = BPF_CALL_IMM(ops->map_pop_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_map_peek_elem:
insn->imm = BPF_CALL_IMM(ops->map_peek_elem);
- continue;
+ goto next_insn;
case BPF_FUNC_redirect_map:
insn->imm = BPF_CALL_IMM(ops->map_redirect);
- continue;
+ goto next_insn;
case BPF_FUNC_for_each_map_elem:
insn->imm = BPF_CALL_IMM(ops->map_for_each_callback);
- continue;
+ goto next_insn;
case BPF_FUNC_map_lookup_percpu_elem:
insn->imm = BPF_CALL_IMM(ops->map_lookup_percpu_elem);
- continue;
+ goto next_insn;
}
goto patch_call_imm;
@@ -19840,7 +20039,7 @@ patch_map_ops_generic:
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement bpf_get_func_arg inline. */
@@ -19865,7 +20064,7 @@ patch_map_ops_generic:
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement bpf_get_func_ret inline. */
@@ -19893,7 +20092,7 @@ patch_map_ops_generic:
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement get_func_arg_cnt inline. */
@@ -19908,7 +20107,7 @@ patch_map_ops_generic:
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement bpf_get_func_ip inline. */
@@ -19923,7 +20122,7 @@ patch_map_ops_generic:
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
/* Implement bpf_kptr_xchg inline */
@@ -19941,7 +20140,7 @@ patch_map_ops_generic:
delta += cnt - 1;
env->prog = prog = new_prog;
insn = new_prog->insnsi + i + delta;
- continue;
+ goto next_insn;
}
patch_call_imm:
fn = env->ops->get_func_proto(insn->imm, env->prog);
@@ -19955,6 +20154,40 @@ patch_call_imm:
return -EFAULT;
}
insn->imm = fn->func - __bpf_call_base;
+next_insn:
+ if (subprogs[cur_subprog + 1].start == i + delta + 1) {
+ subprogs[cur_subprog].stack_depth += stack_depth_extra;
+ subprogs[cur_subprog].stack_extra = stack_depth_extra;
+ cur_subprog++;
+ stack_depth = subprogs[cur_subprog].stack_depth;
+ stack_depth_extra = 0;
+ }
+ i++;
+ insn++;
+ }
+
+ env->prog->aux->stack_depth = subprogs[0].stack_depth;
+ for (i = 0; i < env->subprog_cnt; i++) {
+ int subprog_start = subprogs[i].start;
+ int stack_slots = subprogs[i].stack_extra / 8;
+
+ if (!stack_slots)
+ continue;
+ if (stack_slots > 1) {
+ verbose(env, "verifier bug: stack_slots supports may_goto only\n");
+ return -EFAULT;
+ }
+
+ /* Add ST insn to subprog prologue to init extra stack */
+ insn_buf[0] = BPF_ST_MEM(BPF_DW, BPF_REG_FP,
+ -subprogs[i].stack_depth, BPF_MAX_LOOPS);
+ /* Copy first actual insn to preserve it */
+ insn_buf[1] = env->prog->insnsi[subprog_start];
+
+ new_prog = bpf_patch_insn_data(env, subprog_start, insn_buf, 2);
+ if (!new_prog)
+ return -ENOMEM;
+ env->prog = prog = new_prog;
}
/* Since poke tab is now finalized, publish aux to tracker. */
@@ -20230,6 +20463,9 @@ static int do_check_common(struct bpf_verifier_env *env, int subprog)
reg->btf = bpf_get_btf_vmlinux(); /* can't fail at this point */
reg->btf_id = arg->btf_id;
reg->id = ++env->id_gen;
+ } else if (base_type(arg->arg_type) == ARG_PTR_TO_ARENA) {
+ /* caller can pass either PTR_TO_ARENA or SCALAR */
+ mark_reg_unknown(env, regs, i);
} else {
WARN_ONCE(1, "BUG: unhandled arg#%d type %d\n",
i - BPF_REG_1, arg->arg_type);
@@ -20705,7 +20941,7 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
}
}
- if (prog->aux->sleepable) {
+ if (prog->sleepable) {
ret = -EINVAL;
switch (prog->type) {
case BPF_PROG_TYPE_TRACING:
@@ -20816,14 +21052,14 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
u64 key;
if (prog->type == BPF_PROG_TYPE_SYSCALL) {
- if (prog->aux->sleepable)
+ if (prog->sleepable)
/* attach_btf_id checked to be zero already */
return 0;
verbose(env, "Syscall programs can only be sleepable\n");
return -EINVAL;
}
- if (prog->aux->sleepable && !can_be_sleepable(prog)) {
+ if (prog->sleepable && !can_be_sleepable(prog)) {
verbose(env, "Only fentry/fexit/fmod_ret, lsm, iter, uprobe, and struct_ops programs can be sleepable\n");
return -EINVAL;
}