[PATCH] tracing: probes: Fix to zero initialize a local variable

From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>,
	mhiramat@kernel.org, linux-trace-kernel@vger.kernel.org
Subject: [PATCH] tracing: probes: Fix to zero initialize a local variable
Date: Wed, 20 Mar 2024 17:10:38 +0900	[thread overview]
Message-ID: <171092223833.237219.17304490075697026697.stgit@devnote2> (raw)
In-Reply-To: <b010488e-68aa-407c-add0-3e059254aaa0@moroto.mountain>

From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Fix to initialize 'val' local variable with zero.
Dan reported that Smatch static code checker reports an error that a local
'val' variable needs to be initialized. Actually, the 'val' is expected to
be initialized by FETCH_OP_ARG in the same loop, but it is not obvious. So
initialize it with zero.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/b010488e-68aa-407c-add0-3e059254aaa0@moroto.mountain/
Fixes: 25f00e40ce79 ("tracing/probes: Support $argN in return probe (kprobe and fprobe)")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
 kernel/trace/trace_probe.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 217169de0920..dfe3ee6035ec 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -839,7 +839,7 @@ int traceprobe_get_entry_data_size(struct trace_probe *tp)
 void store_trace_entry_data(void *edata, struct trace_probe *tp, struct pt_regs *regs)
 {
 	struct probe_entry_arg *earg = tp->entry_arg;
-	unsigned long val;
+	unsigned long val = 0;
 	int i;
 
 	if (!earg)

