From 24bc80887adb4d6fc0057d4f14fabeaa4502b2a0 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Thu, 6 Apr 2023 16:41:53 -0700 Subject: [PATCH] bpf: Ignore verifier log reset in BPF_LOG_KERNEL mode Verifier log position reset is meaningless in BPF_LOG_KERNEL mode, so just exit early in bpf_vlog_reset() if log->level is BPF_LOG_KERNEL. This avoid meaningless put_user() into NULL log->ubuf. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Lorenz Bauer Link: https://lore.kernel.org/bpf/20230406234205.323208-8-andrii@kernel.org --- kernel/bpf/log.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c index 92b1c8ad6601..d99a50f07187 100644 --- a/kernel/bpf/log.c +++ b/kernel/bpf/log.c @@ -106,7 +106,7 @@ void bpf_vlog_reset(struct bpf_verifier_log *log, u64 new_pos) if (WARN_ON_ONCE(new_pos > log->end_pos)) return; - if (!bpf_verifier_log_needed(log)) + if (!bpf_verifier_log_needed(log) || log->level == BPF_LOG_KERNEL) return; /* if position to which we reset is beyond current log window,