diff options
| author | Alexei Starovoitov <ast@kernel.org> | 2023-03-13 13:20:58 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-03-13 13:21:22 -0700 |
| commit | a33a6eaa19d3af261e8708bfc8ba62020703117f (patch) | |
| tree | 9cabe0038dc0fe546b994a4c915612f204004067 /kernel | |
| parent | e8c8361cfdbf450f760e8a2bdbd4222d1947366b (diff) | |
| parent | bf9bec4cb3a401a14c24a7ef937d3c26aff9ad60 (diff) | |
Merge branch 'bpf: Allow reads from uninit stack'
Merge commit bf9bec4cb3a4 ("Merge branch 'bpf: Allow reads from uninit stack'")
from bpf-next to bpf tree to address verification issues in some programs
due to stack usage.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 272563a0b770..d517d13878cf 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3826,6 +3826,8 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, continue; if (type == STACK_MISC) continue; + if (type == STACK_INVALID && env->allow_uninit_stack) + continue; verbose(env, "invalid read from stack off %d+%d size %d\n", off, i, size); return -EACCES; @@ -3863,6 +3865,8 @@ static int check_stack_read_fixed_off(struct bpf_verifier_env *env, continue; if (type == STACK_ZERO) continue; + if (type == STACK_INVALID && env->allow_uninit_stack) + continue; verbose(env, "invalid read from stack off %d+%d size %d\n", off, i, size); return -EACCES; @@ -5754,7 +5758,8 @@ static int check_stack_range_initialized( stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE]; if (*stype == STACK_MISC) goto mark; - if (*stype == STACK_ZERO) { + if ((*stype == STACK_ZERO) || + (*stype == STACK_INVALID && env->allow_uninit_stack)) { if (clobber) { /* helper can write anything into the stack */ *stype = STACK_MISC; @@ -13936,6 +13941,10 @@ static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old, if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_INVALID) continue; + if (env->allow_uninit_stack && + old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_MISC) + continue; + /* explored stack has more populated slots than current stack * and these slots were used */ |