Re: [PATCH] perf tools: Check for null when copying nsinfo.

From: Namhyung Kim
Date: Fri Aug 10 2018 - 00:55:42 EST


Hello,

On Thu, Aug 09, 2018 at 11:53:48PM +0200, Benno Evers wrote:
> The argument to nsinfo__copy() was assumed to be valid, but some code paths
> exist that will lead to NULL being passed.
>
> In particular, running 'perf script -D' on a perf.data file containing an
> PERF_RECORD_MMAP event associating the '[vdso]' dso with pid 0 earlier in
> the event stream will lead to a segfault.
>
> Since all calling code is already checking for a non-null return value,
> just return NULL for this case as well.

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

It seems you missed the Signed-off-by though.

Thanks,
Namhyung


> ---
> tools/perf/util/namespaces.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/perf/util/namespaces.c b/tools/perf/util/namespaces.c
> index 5be021701f34..cf8bd123cf73 100644
> --- a/tools/perf/util/namespaces.c
> +++ b/tools/perf/util/namespaces.c
> @@ -139,6 +139,9 @@ struct nsinfo *nsinfo__copy(struct nsinfo *nsi)
> {
> struct nsinfo *nnsi;
>
> + if (nsi == NULL)
> + return NULL;
> +
> nnsi = calloc(1, sizeof(*nnsi));
> if (nnsi != NULL) {
> nnsi->pid = nsi->pid;
> --
> 2.17.1
>