RepoMirrors/ffmpeg
1
0
Fork 0
mirror of https://git.ffmpeg.org/ffmpeg.git synced 2024-12-15 19:55:08 +00:00
Code Issues Projects Releases Wiki Activity

avformat/mov: fix integer overflow

Browse Source 
Partially fixes Ticket 4727.

-duration is not a safe expression, since duration can be INT_MIN.
One might ask how it can become INT_MIN.
Although it is true that line 2574 is no longer reached with INT_MIN due
to commit 053e80f6ea (which fixed another
integer overflow issue), mov_update_dts_shift is called on line 3549 as
well, right after a read of untrusted data.
One can do the fix locally there, but that function is already a huge
mess. Changing mov_update_dts_shift is likely better.

This changes duration to INT_MIN + 1 in such cases. This should not make any
practical difference since such streams are anyway fuzzer files.

Tested with FATE.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This commit is contained in:
Ganesh Ajjanagadde 2015-10-10 13:39:28 -04:00
parent 4c8ca76965
commit d59bfcd112
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
libavformat/mov.c
View File

@ -2521,6 +2521,10 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
static void mov_update_dts_shift(MOVStreamContext *sc, int duration)
{
if (duration < 0) {
if (duration == INT_MIN) {
av_log(NULL, AV_LOG_WARNING, "mov_update_dts_shift(): dts_shift set to %d\n", INT_MAX);
duration++;
}
sc->dts_shift = FFMAX(sc->dts_shift, -duration);
}
}