Re: [PATCH perf/core v5 04/15] perf probe: Add --cache option to cache the probe definitions

From: Masami Hiramatsu
Date: Thu Apr 28 2016 - 19:14:44 EST


On Thu, 28 Apr 2016 11:12:19 +0900
Namhyung Kim <namhyung@xxxxxxxxxx> wrote:

> On Thu, Apr 28, 2016 at 03:37:42AM +0900, Masami Hiramatsu wrote:
> > From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
> >
> > Add --cache option to cache the probe definitions. This
> > just saves the result of the dwarf analysis to probe cache.
> >
> > Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
> > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > ---
> > Changes in v5:
> > - Move probe_cache* definitions. (code cleanup)
> >
> > Changes in v4:
> > - Remove cache saving failure message.
> > ---
>
> [snip]
> > +static int probe_cache__load(struct probe_cache *pcache)
> > +{
> > + struct probe_cache_entry *entry = NULL;
> > + char buf[MAX_CMDLEN], *p;
> > + int ret = 0;
> > + FILE *fp;
> > +
> > + fp = fdopen(dup(pcache->fd), "r");
> > + while (!feof(fp)) {
> > + if (!fgets(buf, MAX_CMDLEN, fp))
> > + break;
> > + p = strchr(buf, '\n');
> > + if (p)
> > + *p = '\0';
> > + if (buf[0] == '#') { /* #perf_probe_event */
> > + entry = probe_cache_entry__new(NULL);
>
> The probe_cache_entry__new() can fail.

Good catch!

>
> Thanks,
> Namhyung
>
>
> > + entry->spev = strdup(buf + 1);

Moreover, if this strdup fail, this goes to return but retvalue is 0...

I'll fix this too.

Thank you!

--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>