From ccf25a67c7e29cfa6815d193054789b45ef825ad Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Thu, 18 Sep 2025 19:18:41 -0700 Subject: bpf: signal error if old liveness is more conservative than new Unlike the new algorithm, register chain based liveness tracking is fully path sensitive, and thus should be strictly more accurate. Validate the new algorithm by signaling an error whenever it considers a stack slot dead while the old algorithm considers it alive. Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20250918-callchain-sensitive-liveness-v3-8-c3cd27bacc60@gmail.com Signed-off-by: Alexei Starovoitov --- include/linux/bpf_verifier.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 2e3bdd50e2ba..dec5da3a2e59 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -852,6 +852,7 @@ struct bpf_verifier_env { /* array of pointers to bpf_scc_info indexed by SCC id */ struct bpf_scc_info **scc_info; u32 scc_cnt; + bool internal_error; }; static inline struct bpf_func_info_aux *subprog_aux(struct bpf_verifier_env *env, int subprog) -- cgit