RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

avformat/matroskadec: Check desc_bytes 

Fixes: Division by 0
Fixes: 44035/clusterfuzz-testcase-minimized-ffmpeg_dem_WEBM_DASH_MANIFEST_fuzzer-4826721386364928

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 5038933977)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2022-02-05 20:37:22 +01:00
parent 2edb753825
commit 7eebf00ff0
1 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
libavformat/matroskadec.c
View File

@ -3850,12 +3850,16 @@ static int64_t webm_dash_manifest_compute_bandwidth(AVFormatContext *s, int64_t
do { do {
int64_t desc_bytes = desc_end.end_offset - desc_beg.start_offset; int64_t desc_bytes = desc_end.end_offset - desc_beg.start_offset;
int64_t desc_ns = desc_end.end_time_ns - desc_beg.start_time_ns; int64_t desc_ns = desc_end.end_time_ns - desc_beg.start_time_ns;
double desc_sec = desc_ns / nano_seconds_per_second; double desc_sec, calc_bits_per_second, percent, mod_bits_per_second;
double calc_bits_per_second = (desc_bytes * 8) / desc_sec; if (desc_bytes <= 0)
return -1;
desc_sec = desc_ns / nano_seconds_per_second;
calc_bits_per_second = (desc_bytes * 8) / desc_sec;
// Drop the bps by the percentage of bytes buffered. // Drop the bps by the percentage of bytes buffered.
double percent = (desc_bytes - prebuffer_bytes) / desc_bytes; percent = (desc_bytes - prebuffer_bytes) / desc_bytes;
double mod_bits_per_second = calc_bits_per_second * percent; mod_bits_per_second = calc_bits_per_second * percent;
if (prebuffer < desc_sec) { if (prebuffer < desc_sec) {
double search_sec = double search_sec =