On Thu, Jun 27, 2024 at 08:40:00AM +0200, Paul B Mahol wrote: > On Thu, Jun 27, 2024 at 1:50 AM Michael Niedermayer > wrote: > > > On Tue, Jun 25, 2024 at 09:27:55PM +0200, Anton Khirnov wrote: > > > Quoting Michael Niedermayer (2024-06-25 21:25:46) > > > > On Thu, Mar 28, 2024 at 12:27:02AM +0100, Michael Niedermayer wrote: > > > > > On Wed, Mar 27, 2024 at 08:39:17AM +0100, Anton Khirnov wrote: > > > > > > Quoting Michael Niedermayer (2024-03-23 00:08:16) > > > > > > > Fixes: Timeout > > > > > > > Fixes: > > 67044/clusterfuzz-testcase-minimized-ffmpeg_dem_CAF_fuzzer-5791144363491328 > > > > > > > > > > > > > > Found-by: continuous fuzzing process > > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > > > > > > > Signed-off-by: Michael Niedermayer > > > > > > > --- > > > > > > > libavformat/cafdec.c | 5 +++++ > > > > > > > 1 file changed, 5 insertions(+) > > > > > > > > > > > > > > diff --git a/libavformat/cafdec.c b/libavformat/cafdec.c > > > > > > > index 426c56b9bd..334077efb5 100644 > > > > > > > --- a/libavformat/cafdec.c > > > > > > > +++ b/libavformat/cafdec.c > > > > > > > @@ -33,6 +33,7 @@ > > > > > > > #include "isom.h" > > > > > > > #include "mov_chan.h" > > > > > > > #include "libavcodec/flac.h" > > > > > > > +#include "libavcodec/internal.h" > > > > > > > #include "libavutil/intreadwrite.h" > > > > > > > #include "libavutil/intfloat.h" > > > > > > > #include "libavutil/dict.h" > > > > > > > @@ -87,6 +88,10 @@ static int read_desc_chunk(AVFormatContext *s) > > > > > > > st->codecpar->ch_layout.nb_channels = avio_rb32(pb); > > > > > > > st->codecpar->bits_per_coded_sample = avio_rb32(pb); > > > > > > > > > > > > > > + if (st->codecpar->ch_layout.nb_channels > > > FF_SANE_NB_CHANNELS || > > > > > > > > > > > > I dislike this. > > > > > > > > > > I dislike it too > > > > > > > > so what do we do about this ? > > > > > > About what? What is the actual problem that needs addressed? > > > > 67044/clusterfuzz-testcase-minimized-ffmpeg_dem_CAF_fuzzer-5791144363491328 > > > > > > > > > > > any objections to apply this ? > > > > > > yes, FF_SANE_NB_CHANNELS is a hack that should be removed, not spread > > > > a maximum number for each theoretically unlimited parameter is desirable > > This can be a user setable value or a compile time value when such is > > preferred. > > > > Cant you check if so many channels are actually available in stream? Iam not sure how. Maybe there is a way ... > Or there is some silly loop that goes unchecked up to INT32_MAX ? there are multiple loops one is in av_channel_layout_custom_init() another is in av_channel_layout_describe_bprint() thx [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Freedom in capitalist society always remains about the same as it was in ancient Greek republics: Freedom for slave owners. -- Vladimir Lenin