6.6-stable review patch. If anyone has any objections, please let me know.
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From: Leon Hwang hffilwlqm@gmail.com
[ Upstream commit 01793ed86b5d7df1e956520b5474940743eb7ed8 ]
It's confusing to inspect 'prog->aux->tail_call_reachable' with drgn[0], when bpf prog has tail call but 'tail_call_reachable' is false.
This patch corrects 'tail_call_reachable' when bpf prog has tail call.
Signed-off-by: Leon Hwang hffilwlqm@gmail.com Link: https://lore.kernel.org/r/20240610124224.34673-2-hffilwlqm@gmail.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/verifier.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3f1a9cd7fc9e..9d5699942273 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3064,8 +3064,10 @@ static int check_subprogs(struct bpf_verifier_env *env)
if (code == (BPF_JMP | BPF_CALL) && insn[i].src_reg == 0 && - insn[i].imm == BPF_FUNC_tail_call) + insn[i].imm == BPF_FUNC_tail_call) { subprog[cur_subprog].has_tail_call = true; + subprog[cur_subprog].tail_call_reachable = true; + } if (BPF_CLASS(code) == BPF_LD && (BPF_MODE(code) == BPF_ABS || BPF_MODE(code) == BPF_IND)) subprog[cur_subprog].has_ld_abs = true;