[FFmpeg-devel] [PATCH v1] avcodec/vp9_superframe_split_bsf: Fix for possible null pointer dereference

[Dawid Kozinski/Multimedia (PLT) /SRPOL/Staff Engineer/Samsung Electronics]

Oops, you're absolutely right. I can't believe I missed ff_bsf_get_packet_ref. 
My apologies for the false alarm. 
It's a lesson for me to be more attentive.

Dawid

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Andreas Rheinhardt
> Sent: piątek, 6 października 2023 15:11
> To: ffmpeg-devel at ffmpeg.org
> Subject: Re: [FFmpeg-devel] [PATCH v1] avcodec/vp9_superframe_split_bsf: Fix
> for possible null pointer dereference
> 
> Dawid Kozinski/Multimedia (PLT) /SRPOL/Staff Engineer/Samsung Electronics:
> >
> > Pointer  ctx->priv_data->buffer_pkt->data, that can have only NULL value
> (checked at vp9_superframe_split_bsf.c:48), is dereferenced at
> vp9_superframe_split_bsf.c:57.
> >
> 
> The rationale for a patch should be included in the commit message and not be
> sent as a reply to the actual patch.
> 
> The warning is nonsense and you are breaking the whole BSF with this patch. It is
> perfectly normal for buffer_pkt->data to be NULL at line 48 and to be != NULL at
> line 57: There is a ff_bsf_get_packet_ref() in between which fills the packet.
> 
> - Andreas
> 
> >
> >> -----Original Message-----
> >> From: Dawid Kozinski <d.kozinski at samsung.com>
> >> Sent: piątek, 6 października 2023 13:02
> >> To: d.frankiewic at samsung.com; ffmpeg-devel at ffmpeg.org
> >> Cc: Dawid Kozinski <d.kozinski at samsung.com>
> >> Subject: [PATCH v1] avcodec/vp9_superframe_split_bsf: Fix for
> >> possible null pointer dereference
> >>
> >> Signed-off-by: Dawid Kozinski <d.kozinski at samsung.com>
> >> ---
> >>  libavcodec/vp9_superframe_split_bsf.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/libavcodec/vp9_superframe_split_bsf.c
> >> b/libavcodec/vp9_superframe_split_bsf.c
> >> index cddd48119c..4f94afc6d9 100644
> >> --- a/libavcodec/vp9_superframe_split_bsf.c
> >> +++ b/libavcodec/vp9_superframe_split_bsf.c
> >> @@ -45,7 +45,7 @@ static int vp9_superframe_split_filter(AVBSFContext
> >> *ctx, AVPacket *out)
> >>      int i, j, ret, marker;
> >>      int is_superframe = !!s->buffer_pkt->data;
> >>
> >> -    if (!s->buffer_pkt->data) {
> >> +    if (s->buffer_pkt->data) {
> >>          ret = ff_bsf_get_packet_ref(ctx, s->buffer_pkt);
> >>          if (ret < 0)
> >>              return ret;
> >> --
> >> 2.25.1
> >
> >
> 
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://protect2.fireeye.com/v1/url?k=17d2741b-76af9c5c-17d3ff54-
> 74fe485fff30-c67cc2f5726cb1a6&q=1&e=84d99260-3508-4d83-bca4-
> 3e475cf427c4&u=https%3A%2F%2Fffmpeg.org%2Fmailman%2Flistinfo%2Fffmp
> eg-devel
> 
> To unsubscribe, visit link above, or email ffmpeg-devel-request at ffmpeg.org
> with subject "unsubscribe".