[FFmpeg-cvslog] avcodec/dnxhd_parser: Fix parser when input does not have nicely sized packets

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Jul  6 11:51:09 2019 +0200| [2d900d8fe0aaf9c984e024956eb537ecdfe2c949] | committer: Michael Niedermayer

avcodec/dnxhd_parser: Fix parser when input does not have nicely sized packets

Fixes: out of array access
Fixes: 15522/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DNXHD_fuzzer-5747756078989312

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=2d900d8fe0aaf9c984e024956eb537ecdfe2c949
---

 libavcodec/dnxhd_parser.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavcodec/dnxhd_parser.c b/libavcodec/dnxhd_parser.c
index 31a3158fea..63b4ff89e1 100644
--- a/libavcodec/dnxhd_parser.c
+++ b/libavcodec/dnxhd_parser.c
@@ -79,8 +79,9 @@ static int dnxhd_find_frame_end(DNXHDParserContext *dctx,
                     if (remaining <= 0)
                         continue;
                 }
+                remaining += i - 47;
                 dctx->remaining = remaining;
-                if (buf_size - i + 47 >= dctx->remaining) {
+                if (buf_size >= dctx->remaining) {
                     pc->frame_start_found = 0;
                     pc->state64 = -1;
                     dctx->cur_byte = 0;