Subject: Re: [PATCH v2] tracing: check the return value of kstrdup()

From: Masami Hiramatsu <[email-masked]>
Date: Thu, 6 Jan 2022 07:35:54 +0900

On Wed, 5 Jan 2022 17:10:49 -0500
Steven Rostedt <[email-masked]> wrote:

> Masami, can you ack this ?

Yes, this is actual bug. Thanks for fixing!

Acked-by: Masami Hiramatsu <[email-masked]>
Fixes: 33ea4b24277b ("perf/core: Implement the 'perf_uprobe' PMU")

> 
> -- Steve
> 
> 
> On Tue, 14 Dec 2021 09:28:02 +0800
> [email-masked] wrote:
> 
> > From: Xiaoke Wang <[email-masked]>
> > 
> > kstrdup() returns NULL when some internal memory errors happen, it is
> > better to check the return value of it so to catch the memory error in
> > time.
> > 
> > Signed-off-by: Xiaoke Wang <[email-masked]>
> > ---
> > Changelogs:
> > Compare with the last email, this one is using my full name.
> > And I am sorry that I did not notice the bugs in trace_boot.c had been
> > already patched. So I removed the content about trace_boot.c.
> > ---
> >  kernel/trace/trace_uprobe.c | 5 +++++
> >  1 files changed, 5 insertions(+)
> > 
> > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
> > index 225ce56..173ff0f 100644
> > --- a/kernel/trace/trace_uprobe.c
> > +++ b/kernel/trace/trace_uprobe.c
> > @@ -1618,6 +1618,11 @@ create_local_trace_uprobe(char *name, unsigned long offs,
> >  	tu->path = path;
> >  	tu->ref_ctr_offset = ref_ctr_offset;
> >  	tu->filename = kstrdup(name, GFP_KERNEL);
> > +	if (!tu->filename) {
> > +		ret = -ENOMEM;
> > +		goto error;
> > +	}
> > +
> >  	init_trace_event_call(tu);
> >  
> >  	ptype = is_ret_probe(tu) ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
> 

-- 
Masami Hiramatsu <[email-masked]>