[FFmpeg-devel] [PATCH 4/8] avformat/mxfdec: Fix file position addition

[Michael Niedermayer]

Not sure this is the best solution, maybe a more general solution limiting the avio_tell() output to less than 63bit would be a better option
Fixes: signed integer overflow: 9223372036854775805 + 4 cannot be represented in type 'long'
Fixes: 29927/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer-5579985228267520

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/mxfdec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index afff20402d..97a1b749fe 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -2861,7 +2861,7 @@ static int mxf_read_local_tags(MXFContext *mxf, KLVPacket *klv, MXFMetadataReadF
         return AVERROR(ENOMEM);
     if (ctx_size)
         mxf_metadataset_init(ctx, type);
-    while (avio_tell(pb) + 4 < klv_end && !avio_feof(pb)) {
+    while (avio_tell(pb) + (uint64_t)4 < klv_end && !avio_feof(pb)) {
         int ret;
         int tag = avio_rb16(pb);
         int size = avio_rb16(pb); /* KLV specified by 0x53 */
-- 
2.17.1