[FFmpeg-cvslog] avcodec/h264_ps: Check offset_for_non_ref_pic, offset_for_top_to_bottom_field and offset_for_ref_frame

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat May 11 19:36:55 2019 +0200| [7c6f2bfdb25ccadf6ba82dc72eaad1b692122d9a] | committer: Michael Niedermayer

avcodec/h264_ps: Check offset_for_non_ref_pic, offset_for_top_to_bottom_field and offset_for_ref_frame

Fixes: signed integer overflow: -2147483648 + -1 cannot be represented in type 'int'
Fixes: 14444/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5675880333967360

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=7c6f2bfdb25ccadf6ba82dc72eaad1b692122d9a
---

 libavcodec/h264_ps.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/libavcodec/h264_ps.c b/libavcodec/h264_ps.c
index 7c92c68b38..e8738d8502 100644
--- a/libavcodec/h264_ps.c
+++ b/libavcodec/h264_ps.c
@@ -451,6 +451,15 @@ int ff_h264_decode_seq_parameter_set(GetBitContext *gb, AVCodecContext *avctx,
         sps->delta_pic_order_always_zero_flag = get_bits1(gb);
         sps->offset_for_non_ref_pic           = get_se_golomb_long(gb);
         sps->offset_for_top_to_bottom_field   = get_se_golomb_long(gb);
+
+        if (   sps->offset_for_non_ref_pic         == INT32_MIN
+            || sps->offset_for_top_to_bottom_field == INT32_MIN
+        ) {
+            av_log(avctx, AV_LOG_ERROR,
+                   "offset_for_non_ref_pic or offset_for_top_to_bottom_field is out of range\n");
+            goto fail;
+        }
+
         sps->poc_cycle_length                 = get_ue_golomb(gb);
 
         if ((unsigned)sps->poc_cycle_length >=
@@ -460,8 +469,14 @@ int ff_h264_decode_seq_parameter_set(GetBitContext *gb, AVCodecContext *avctx,
             goto fail;
         }
 
-        for (i = 0; i < sps->poc_cycle_length; i++)
+        for (i = 0; i < sps->poc_cycle_length; i++) {
             sps->offset_for_ref_frame[i] = get_se_golomb_long(gb);
+            if (sps->offset_for_ref_frame[i] == INT32_MIN) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "offset_for_ref_frame is out of range\n");
+                goto fail;
+            }
+        }
     } else if (sps->poc_type != 2) {
         av_log(avctx, AV_LOG_ERROR, "illegal POC type %d\n", sps->poc_type);
         goto fail;