Hi Ronald, On Sun, Oct 15, 2017 at 12:21 AM, Ronald S. Bultje <rsbul...@gmail.com> wrote: > Hi Umair, > > On Sat, Oct 14, 2017 at 1:43 PM, Umair Khan <omerj...@gmail.com> wrote: > >> On Sat, Oct 14, 2017 at 8:02 PM, Ronald S. Bultje <rsbul...@gmail.com> >> wrote: >> > Hi Umair, >> > >> > On Sat, Oct 14, 2017 at 9:59 AM, Umair Khan <omerj...@gmail.com> wrote: >> > >> >> I tested the file which Michael sent. The thing is that I'm getting >> >> error in decoding that file in both the cases, with or without the >> >> patch. I will begin debugging this issue, however I think the file >> >> which Michael sent has got nothing to do with the patch in this >> >> thread. >> >> >> > >> > I don't think the file is meant to be decoded correctly, it's a specially >> > crafted file to demonstrate that certain codepaths (triggered by files >> such >> > as this) can be used to trigger unwanted behaviour (overreads, >> overwrites, >> > etc.). Eventually, combinations of such files can be used to break into >> > your system with specially crafted media files (yes, really). >> > >> > Your patch introduces such a security issue (since it's triggered by the >> > file after, but not before the patch). This must be fixed before the >> patch >> > can be committed. >> >> Okay. You mean the file isn't supposed to be decoded and that the als >> decoder should output the proper error message instead of breaking at >> a random point. Am I getting it correct? >> > > More specifically: after your patch, you'll notice that address sanitizer > (clang -fsanitize=address) or valgrind output warnings when decoding this > file. These warnings should be tracked down and fixed.
I tried decoding the file in both the cases and I don't see any address related error in the console while decoding. Following is the output after I apply the patch :- ➜ FFmpeg git:(master) ✗ ffmpeg -i ~/Downloads/abd3c041acbcb816be113455d138166b-asan_heap-oob_b11634_3707_cov_1707137151_als_05_2ch48k16b.mp4 out.mp4 ffmpeg version N-87928-g247281e805 Copyright (c) 2000-2017 the FFmpeg developers built with Apple LLVM version 9.0.0 (clang-900.0.38) configuration: --prefix=/usr/local --enable-gpl --enable-nonfree --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libopus --enable-libxvid libavutil 55. 79.100 / 55. 79.100 libavcodec 57.108.101 / 57.108.101 libavformat 57. 84.101 / 57. 84.101 libavdevice 57. 11.100 / 57. 11.100 libavfilter 6.108.100 / 6.108.100 libswscale 4. 9.100 / 4. 9.100 libswresample 2. 10.100 / 2. 10.100 libpostproc 54. 8.100 / 54. 8.100 Guessed Channel Layout for Input Stream #0.0 : stereo Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/Users/mohammadumair/Downloads/abd3c041acbcb816be113455d138166b-asan_heap-oob_b11634_3707_cov_1707137151_als_05_2ch48k16b.mp4': Metadata: major_brand : mt42 minor_version : 0 compatible_brands: mp42i{om creation_time : 2008-01-21T14:37:08.000000Z Duration: 00:00:14.81, start: 0.000000, bitrate: 436 kb/s Stream #0:0(und): Audio: mp4als (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 435 kb/s (default) Metadata: creation_time : 2008-01-24T15:26:12.000000Z File 'out.mp4' already exists. Overwrite ? [y/N] y Stream mapping: Stream #0:0 -> #0:0 (mp4als (als) -> aac (native)) Press [q] to stop, [?] for help [als @ 0x7fc2df001200] r overflow [als @ 0x7fc2df001200] Reading frame data failed. Skipping RA unit. Output #0, mp4, to 'out.mp4': Metadata: major_brand : mt42 minor_version : 0 compatible_brands: mp42i{om encoder : Lavf57.84.101 Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp (16 bit), 128 kb/s (default) Metadata: creation_time : 2008-01-24T15:26:12.000000Z encoder : Lavc57.108.101 aac size= 2kB time=00:00:00.06 bitrate= 217.0kbits/s speed=7.48x video:0kB audio:1kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 90.142387% [aac @ 0x7fc2df002a00] Qavg: 16482.379 Is there something which I'm missing? -Umair _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel