Re: [PATCH] tracing: probes: Fix to zero initialize a local variable
On Wed, 20 Mar 2024 09:27:49 -0400 Steven Rostedt wrote: > On Wed, 20 Mar 2024 17:10:38 +0900 > "Masami Hiramatsu (Google)" wrote: > > > From: Masami Hiramatsu (Google) > > > > 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. > > BTW, that loop should really have a comment stating that FETCH_OP_ARG is > expected to happen before FETCH_OP_ST_EDATA. Indeed, OK, let me add it. Thank you, > > -- Steve -- Masami Hiramatsu (Google)
Re: [PATCH] tracing: probes: Fix to zero initialize a local variable
On Wed, 20 Mar 2024 17:10:38 +0900 "Masami Hiramatsu (Google)" wrote: > From: Masami Hiramatsu (Google) > > 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. BTW, that loop should really have a comment stating that FETCH_OP_ARG is expected to happen before FETCH_OP_ST_EDATA. -- Steve
Re: [PATCH] tracing: probes: Fix to zero initialize a local variable
On Wed, 20 Mar 2024 17:10:38 +0900
"Masami Hiramatsu (Google)" wrote:
> From: Masami Hiramatsu (Google)
>
> 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
> 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)
> ---
Reviewed-by: Steven Rostedt (Google)
-- Steve
> 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)
[PATCH] tracing: probes: Fix to zero initialize a local variable
From: Masami Hiramatsu (Google)
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
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)
---
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)
