diff options
| author | Ilya Leoshkevich <iii@linux.ibm.com> | 2023-02-20 19:37:56 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-02-23 00:08:52 +0300 |
| commit | df2ccc180a2e6f6e4343ebee99dcfab4f8af2816 (patch) | |
| tree | 322f1895b986f7b8d04bc9126c36a678727c2c49 | |
| parent | bb035ef0cc91e115faa80187ac8886a7f1914d06 (diff) | |
| download | linux-df2ccc180a2e6f6e4343ebee99dcfab4f8af2816.tar.xz | |
bpf: Check for helper calls in check_subprogs()
The condition src_reg != BPF_PSEUDO_CALL && imm == BPF_FUNC_tail_call
may be satisfied by a kfunc call. This would lead to unnecessarily
setting has_tail_call. Use src_reg == 0 instead.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230220163756.753713-1-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | kernel/bpf/verifier.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 741cb5107536..5cb8b623f639 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2479,8 +2479,8 @@ static int check_subprogs(struct bpf_verifier_env *env) u8 code = insn[i].code; if (code == (BPF_JMP | BPF_CALL) && - insn[i].imm == BPF_FUNC_tail_call && - insn[i].src_reg != BPF_PSEUDO_CALL) + insn[i].src_reg == 0 && + insn[i].imm == BPF_FUNC_tail_call) subprog[cur_subprog].has_tail_call = true; if (BPF_CLASS(code) == BPF_LD && (BPF_MODE(code) == BPF_ABS || BPF_MODE(code) == BPF_IND)) |