diff options
| author | Ilya Leoshkevich <iii@linux.ibm.com> | 2024-07-02 01:40:19 +0200 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2024-07-02 18:31:35 +0200 |
| commit | df34ec9db6f521118895f22795da49f2ec01f8cf (patch) | |
| tree | 5d37f1bd78b5e986b4e96a2e210622fa1d919267 /kernel | |
| parent | da5f8fd1f0d393d5eaaba9ad8c22d1c26bb2bf9b (diff) | |
bpf: Fix atomic probe zero-extension
Zero-extending results of atomic probe operations fails with:
verifier bug. zext_dst is set, but no reg is defined
The problem is that insn_def_regno() handles BPF_ATOMICs, but not
BPF_PROBE_ATOMICs. Fix by adding the missing condition.
Fixes: d503a04f8bc0 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240701234304.14336-2-iii@linux.ibm.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index d3927d819465..e25ad5fb9115 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3217,7 +3217,8 @@ static int insn_def_regno(const struct bpf_insn *insn) case BPF_ST: return -1; case BPF_STX: - if (BPF_MODE(insn->code) == BPF_ATOMIC && + if ((BPF_MODE(insn->code) == BPF_ATOMIC || + BPF_MODE(insn->code) == BPF_PROBE_ATOMIC) && (insn->imm & BPF_FETCH)) { if (insn->imm == BPF_CMPXCHG) return BPF_REG_0; |