| Message ID | CAC9dhghCr-cH2mANtjTcQz9DUDE8vWXnCSntoktZACZB3CoUVw@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel] Segfault calling av_interleaved_write_frame | expand |
| Context | Check | Description |
|---|---|---|
| andriy/ffmpeg-patchwork | fail | Failed to apply patch |
On Sat, Jan 18, 2020 at 10:40 PM Jonathan Noble <jonnobleuk@gmail.com> wrote: > Hello, > > I found I was getting sigsegv when calling av_interleaved_write_frame(). > > From a18f4cb5b86392c5c161878daea8e4b1204881eb Mon Sep 17 00:00:00 2001 > From: jon noble <jonnobleuk@gmail.com> > Date: Sat, 18 Jan 2020 21:33:11 +0000 > Subject: [PATCH] libavformat/mux: prevent segfault in > compute_muxer_pkt_fields() > > --- > libavformat/mux.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/libavformat/mux.c b/libavformat/mux.c > index 8ab5ea8c2b..ea79981fe8 100644 > --- a/libavformat/mux.c > +++ b/libavformat/mux.c > @@ -598,9 +598,11 @@ static int compute_muxer_pkt_fields(AVFormatContext > *s, AVStream *st, AVPacket * > av_log(s, AV_LOG_WARNING, "Encoder did not produce proper pts, > making some up.\n"); > warned = 1; > } > - pkt->dts = > -// pkt->pts= st->cur_dts; > - pkt->pts = st->internal->priv_pts->val; > + if (st->internal->priv_pts == NULL) { > + av_log(s, AV_LOG_WARNING, "Null private stream data.\n"); > + return AVERROR(EINVAL); > + } > + pkt->dts = pkt->pts = st->internal->priv_pts->val; > } > > //calculate dts from pts > -- > 2.25.0 > > Can you give us the command line together with the necessary sample files that allow to reproduce this segfault? - Andreas
Oh, it wasn't via ffmpeg. I was using the library. What is the correct dev mailing list? On Sat, 18 Jan 2020 at 21:45, Andreas Rheinhardt < andreas.rheinhardt@gmail.com> wrote: > On Sat, Jan 18, 2020 at 10:40 PM Jonathan Noble <jonnobleuk@gmail.com> > wrote: > > > Hello, > > > > I found I was getting sigsegv when calling av_interleaved_write_frame(). > > > > From a18f4cb5b86392c5c161878daea8e4b1204881eb Mon Sep 17 00:00:00 2001 > > From: jon noble <jonnobleuk@gmail.com> > > Date: Sat, 18 Jan 2020 21:33:11 +0000 > > Subject: [PATCH] libavformat/mux: prevent segfault in > > compute_muxer_pkt_fields() > > > > --- > > libavformat/mux.c | 8 +++++--- > > 1 file changed, 5 insertions(+), 3 deletions(-) > > > > diff --git a/libavformat/mux.c b/libavformat/mux.c > > index 8ab5ea8c2b..ea79981fe8 100644 > > --- a/libavformat/mux.c > > +++ b/libavformat/mux.c > > @@ -598,9 +598,11 @@ static int compute_muxer_pkt_fields(AVFormatContext > > *s, AVStream *st, AVPacket * > > av_log(s, AV_LOG_WARNING, "Encoder did not produce proper > pts, > > making some up.\n"); > > warned = 1; > > } > > - pkt->dts = > > -// pkt->pts= st->cur_dts; > > - pkt->pts = st->internal->priv_pts->val; > > + if (st->internal->priv_pts == NULL) { > > + av_log(s, AV_LOG_WARNING, "Null private stream data.\n"); > > + return AVERROR(EINVAL); > > + } > > + pkt->dts = pkt->pts = st->internal->priv_pts->val; > > } > > > > //calculate dts from pts > > -- > > 2.25.0 > > > > Can you give us the command line together with the necessary sample files > that allow to reproduce this segfault? > > - Andreas > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
Jonathan Noble (12020-01-18): > Oh, it wasn't via ffmpeg. I was using the library. What is the correct dev > mailing list? Probably. We would need to see the code with the sample, to be sure where the bug lies. > On Sat, 18 Jan 2020 at 21:45, Andreas Rheinhardt < > andreas.rheinhardt@gmail.com> wrote: Top-posting is not allowed on this mailing-list. If you do not know what it means, look it up. Regards,
On Sat, Jan 18, 2020 at 11:18 PM Jonathan Noble <jonnobleuk@gmail.com> wrote: > Oh, it wasn't via ffmpeg. I was using the library. What is the correct dev > mailing list? > > Your patch was for FFmpeg itself and so this is the right mailing list. But you should nevertheless give us enough information so that we can reproduce the problem. After all, the bug may be in a completely different part than the part where the segfault is triggered. (That being said, doing a separate allocation for priv_pts seems weird in general.) - Andreas PS: Please avoid top-posting on this list.
On Sat, 18 Jan 2020 at 22:20, Nicolas George <george@nsup.org> wrote: > Jonathan Noble (12020-01-18): > > Oh, it wasn't via ffmpeg. I was using the library. What is the correct > dev > > mailing list? > > Probably. We would need to see the code with the sample, to be sure > where the bug lies. > I'm writing a wrapper around libav. https://github.com/jonno85uk/mediahandling/tree/Issue4_encoding I know what was causing this condition, avformat_write_header() hadn't been called at that time. > > > On Sat, 18 Jan 2020 at 21:45, Andreas Rheinhardt < > > andreas.rheinhardt@gmail.com> wrote: > > Top-posting is not allowed on this mailing-list. If you do not know what > it means, look it up. > > Regards, > > -- > Nicolas George > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
Jonathan Noble (12020-01-19): > I'm writing a wrapper around libav. > https://github.com/jonno85uk/mediahandling/tree/Issue4_encoding > I know what was causing this condition, avformat_write_header() hadn't > been called at that time. Calling avformat_write_header() is not optional, writing frames before it is not supported. For questions about the proper usage of the API, see this mailing-list: https://ffmpeg.org/mailman/listinfo/libav-user Regards,
On Sun, 19 Jan 2020 at 11:52, Nicolas George <george@nsup.org> wrote: > Jonathan Noble (12020-01-19): > > I'm writing a wrapper around libav. > > https://github.com/jonno85uk/mediahandling/tree/Issue4_encoding > > I know what was causing this condition, avformat_write_header() hadn't > > been called at that time. > > Calling avformat_write_header() is not optional, writing frames before > it is not supported. I'd gathered that, but rather than bombing out shouldn't there be a AVERROR returned or something else to notify the user of their error, like so many other non-optional checks in ffmpeg? > > For questions about the proper usage of the API, see this mailing-list: > https://ffmpeg.org/mailman/listinfo/libav-user > > Regards, > > -- > Nicolas George > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
Jonathan Noble (12020-01-19): > I'd gathered that, but rather than bombing out shouldn't there be a AVERROR > returned or something else to notify the user of their error, like so many > other non-optional checks in ffmpeg? No. AVERROR codes are not for errors that can be detected statically; these need to be fixed, period. This is not specific to FFmpeg: what do you get for calling fprintf() on a NULL FILE pointer? Regards,
On Sun, 19 Jan 2020 at 22:54, Nicolas George <george@nsup.org> wrote: > Jonathan Noble (12020-01-19): > > I'd gathered that, but rather than bombing out shouldn't there be a > AVERROR > > returned or something else to notify the user of their error, like so > many > > other non-optional checks in ffmpeg? > > No. AVERROR codes are not for errors that can be detected statically; > these need to be fixed, period. > > This is not specific to FFmpeg: what do you get for calling fprintf() on > a NULL FILE pointer? > I wouldn't know. I try my best not to use C. > Regards, > > -- > Nicolas George > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
diff --git a/libavformat/mux.c b/libavformat/mux.c index 8ab5ea8c2b..ea79981fe8 100644 --- a/libavformat/mux.c +++ b/libavformat/mux.c @@ -598,9 +598,11 @@ static int compute_muxer_pkt_fields(AVFormatContext *s, AVStream *st, AVPacket * av_log(s, AV_LOG_WARNING, "Encoder did not produce proper pts, making some up.\n"); warned = 1; } - pkt->dts = -// pkt->pts= st->cur_dts; - pkt->pts = st->internal->priv_pts->val; + if (st->internal->priv_pts == NULL) { + av_log(s, AV_LOG_WARNING, "Null private stream data.\n"); + return AVERROR(EINVAL); + } + pkt->dts = pkt->pts = st->internal->priv_pts->val; }
Hello, I found I was getting sigsegv when calling av_interleaved_write_frame(). From a18f4cb5b86392c5c161878daea8e4b1204881eb Mon Sep 17 00:00:00 2001 From: jon noble <jonnobleuk@gmail.com> Date: Sat, 18 Jan 2020 21:33:11 +0000 Subject: [PATCH] libavformat/mux: prevent segfault in compute_muxer_pkt_fields() --- libavformat/mux.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) //calculate dts from pts