From: Pietro Borrello Date: Sat, 28 Jan 2023 16:23:41 +0000 (+0000) Subject: tracing/probe: trace_probe_primary_from_call(): checked list_first_entry X-Git-Tag: v6.6.7~2731^2~1 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=81d0fa4cb4fc0e1a49c2b22f92c43d9fe972ebcf;p=platform%2Fkernel%2Flinux-starfive.git tracing/probe: trace_probe_primary_from_call(): checked list_first_entry All callers of trace_probe_primary_from_call() check the return value to be non NULL. However, the function returns list_first_entry(&tpe->probes, ...) which can never be NULL. Additionally, it does not check for the list being possibly empty, possibly causing a type confusion on empty lists. Use list_first_entry_or_null() which solves both problems. Link: https://lore.kernel.org/linux-trace-kernel/20230128-list-entry-null-check-v1-1-8bde6a3da2ef@diag.uniroma1.it/ Fixes: 60d53e2c3b75 ("tracing/probe: Split trace_event related data from trace_probe") Signed-off-by: Pietro Borrello Reviewed-by: Steven Rostedt (Google) Acked-by: Masami Hiramatsu (Google) Acked-by: Mukesh Ojha Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) --- diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index ef8ed3b..6a4ecfb 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -308,7 +308,7 @@ trace_probe_primary_from_call(struct trace_event_call *call) { struct trace_probe_event *tpe = trace_probe_event_from_call(call); - return list_first_entry(&tpe->probes, struct trace_probe, list); + return list_first_entry_or_null(&tpe->probes, struct trace_probe, list); } static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp)