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[2a01:cb08:8949:7e00:cb3:32f6:3428:a027]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3b79c453aeasm5481786f8f.40.2025.08.01.02.49.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 01 Aug 2025 02:49:17 -0700 (PDT) Date: Fri, 1 Aug 2025 11:49:15 +0200 From: Paul Chaignon To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Martin KaFai Lau , netfilter-devel@vger.kernel.org, Pablo Neira Ayuso , Jozsef Kadlecsik , Petar Penkov , Florian Westphal Subject: [PATCH bpf 3/4] bpf: Improve ctx access verifier error message Message-ID: References: Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: We've already had two "error during ctx access conversion" warnings triggered by syzkaller. Let's improve the error message by dumping the cnt variable so that we can more easily differentiate between the different error cases. Signed-off-by: Paul Chaignon --- kernel/bpf/verifier.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 399f03e62508..0806295945e4 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -21445,7 +21445,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) &target_size); if (cnt == 0 || cnt >= INSN_BUF_SIZE || (ctx_field_size && !target_size)) { - verifier_bug(env, "error during ctx access conversion"); + verifier_bug(env, "error during ctx access conversion (%d)", cnt); return -EFAULT; } -- 2.43.0