diff options
| -rw-r--r-- | kernel/bpf/verifier.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 303368460ec1..fde5d046b6e3 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -17052,6 +17052,15 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, type_may_be_null(dst_reg->type) && ((BPF_SRC(insn->code) == BPF_K && insn->imm == 0) || (BPF_SRC(insn->code) == BPF_X && bpf_register_is_null(src_reg)))) { + /* + * For BPF_X the zero is a property of this execution path, + * hence src_reg has to be precise. + */ + if (BPF_SRC(insn->code) == BPF_X) { + err = mark_chain_precision(env, insn->src_reg); + if (err) + return err; + } /* Mark all identical registers in each branch as either * safe or unknown depending R == 0 or R != 0 conditional. */ |