[FFmpeg-devel] [PATCH 1/5] avformat/hls: Check target_duration

Michael Niedermayer michael at niedermayer.cc
Mon Mar 21 01:30:52 EET 2022


Fixes: signed integer overflow: 77777777777777 * 1000000 cannot be represented in type 'long long'
Fixes: 45545/clusterfuzz-testcase-minimized-ffmpeg_dem_HLS_fuzzer-6438101247983616

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavformat/hls.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libavformat/hls.c b/libavformat/hls.c
index cf6ef9dfb6..a58c558ffe 100644
--- a/libavformat/hls.c
+++ b/libavformat/hls.c
@@ -819,10 +819,16 @@ static int parse_playlist(HLSContext *c, const char *url,
                                &info);
             new_rendition(c, &info, url);
         } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {
+            int64_t t;
             ret = ensure_playlist(c, &pls, url);
             if (ret < 0)
                 goto fail;
-            pls->target_duration = strtoll(ptr, NULL, 10) * AV_TIME_BASE;
+            t = strtoll(ptr, NULL, 10);
+            if (t < 0 || t >= INT64_MAX / AV_TIME_BASE) {
+                ret = AVERROR_INVALIDDATA;
+                goto fail;
+            }
+            pls->target_duration = t * AV_TIME_BASE;
         } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {
             uint64_t seq_no;
             ret = ensure_playlist(c, &pls, url);
-- 
2.17.1



More information about the ffmpeg-devel mailing list