Re: [PATCH] perf jevents: Fix segfault in perf_pmu__find_events_table

[Yang Jihong]

Hello,

On 2023/9/19 7:55, Namhyung Kim wrote:
> Hello,
>
> On Sun, Sep 17, 2023 at 8:05 PM Yang Jihong <yangjihong1@xxxxxxxxxx> wrote:
> > Before caching the JSON events table, perf_pmu__find_events_table() need
> > to check whether table is empty.
> >
> > For example, AuthenticAMD-15-6B-1 is used. The matching events table cannot
> > be found. As a result, a null pointer is accessed when caching JSON events
> > table, causing segfault.
> >
> > Before:
> >    # perf record -vv true
> >    DEBUGINFOD_URLS=
> >    Using CPUID AuthenticAMD-15-6B-1
> >    Segmentation fault (core dumped)
> >
> > After:
> >    # perf record -vv true
> >    DEBUGINFOD_URLS=
> >    Using CPUID AuthenticAMD-15-6B-1
> >    <SNIP>
> >    [ perf record: Woken up 1 times to write data ]
> >    [ perf record: Captured and wrote 0.005 MB perf.data ]
> >
> > Fixes: 7c52f10c0d4d ("perf pmu: Cache JSON events table")
> > Signed-off-by: Yang Jihong <yangjihong1@xxxxxxxxxx>
>
> Thanks for the fix but please see
>
> https://lore.kernel.org/all/20230913125157.2790375-1-tmricht@xxxxxxxxxxxxx/

Uh.. no notice that there is already a fix, please ignore it.

Thanks,
Yang