avformat/iff: Saturate avio_tell() + 12

Fixes: signed integer overflow: 9223372036854775796 + 12 cannot be represented in type 'long long'
Fixes: 51896/clusterfuzz-testcase-minimized-ffmpeg_dem_IFF_fuzzer-4898373660704768

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 b8e754525c)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2023-09-30 00:56:06 +02:00
parent 42f495fbe1
commit d30403b7a7
No known key found for this signature in database
GPG Key ID: B18E8928B3948D64
1 changed files with 2 additions and 2 deletions

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@ -217,7 +217,7 @@ static int parse_dsd_diin(AVFormatContext *s, AVStream *st, uint64_t eof)
{
AVIOContext *pb = s->pb;
while (avio_tell(pb) + 12 <= eof && !avio_feof(pb)) {
while (av_sat_add64(avio_tell(pb), 12) <= eof && !avio_feof(pb)) {
uint32_t tag = avio_rl32(pb);
uint64_t size = avio_rb64(pb);
uint64_t orig_pos = avio_tell(pb);
@ -254,7 +254,7 @@ static int parse_dsd_prop(AVFormatContext *s, AVStream *st, uint64_t eof)
int dsd_layout[6];
ID3v2ExtraMeta *id3v2_extra_meta;
while (avio_tell(pb) + 12 <= eof && !avio_feof(pb)) {
while (av_sat_add64(avio_tell(pb), 12) <= eof && !avio_feof(pb)) {
uint32_t tag = avio_rl32(pb);
uint64_t size = avio_rb64(pb);
uint64_t orig_pos = avio_tell(pb);