avfilter/af_amerge: Fix segfault upon allocation failure

The amerge filter uses a variable number of inpads and allocates them
in its init function; if all goes well, the number of inpads coincides
with a number stored in the filter's private context. Yet if allocating a
subsequent inpad fails, the uninit function nevertheless uses the number
stored in the private context to determine the number of inpads to free
and not the AVFilterContext's nb_inputs. This will lead to an access
beyond the end of the allocated AVFilterContext.input_pads array and
an invalid free.

Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2020-08-24 05:46:08 +02:00
parent ae5369128a
commit 8f2c1f2cbe
1 changed files with 2 additions and 5 deletions

View File

@ -58,13 +58,10 @@ AVFILTER_DEFINE_CLASS(amerge);
static av_cold void uninit(AVFilterContext *ctx)
{
AMergeContext *s = ctx->priv;
int i;
for (i = 0; i < s->nb_inputs; i++) {
if (ctx->input_pads)
av_freep(&ctx->input_pads[i].name);
}
av_freep(&s->in);
for (unsigned i = 0; i < ctx->nb_inputs; i++)
av_freep(&ctx->input_pads[i].name);
}
static int query_formats(AVFilterContext *ctx)