From: Michael Niedermayer <[email protected]>

And use init_get_bits8 to check for integer overflows while at it.

CC: [email protected]
Signed-off-by: Luca Barbato <[email protected]>
---
 libavcodec/h263dec.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index 6245068..1ac972c 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -401,12 +401,15 @@ int ff_h263_decode_frame(AVCodecContext *avctx, void 
*data, int *got_frame,
     }
 
     if (s->bitstream_buffer_size && (s->divx_packed || buf_size < 20)) // divx 
5.01+/xvid frame reorder
-        init_get_bits(&s->gb, s->bitstream_buffer,
-                      s->bitstream_buffer_size * 8);
+        ret = init_get_bits8(&s->gb, s->bitstream_buffer,
+                             s->bitstream_buffer_size);
     else
-        init_get_bits(&s->gb, buf, buf_size * 8);
+        ret = init_get_bits8(&s->gb, buf, buf_size);
     s->bitstream_buffer_size = 0;
 
+    if (ret < 0)
+        return ret;
+
     if (!s->context_initialized)
         if (ff_MPV_common_init(s) < 0) // we need the idct permutaton for 
reading a custom matrix
             return -1;
@@ -429,9 +432,10 @@ int ff_h263_decode_frame(AVCodecContext *avctx, void 
*data, int *got_frame,
         if (s->avctx->extradata_size && s->picture_number == 0) {
             GetBitContext gb;
 
-            init_get_bits(&gb, s->avctx->extradata,
-                          s->avctx->extradata_size * 8);
-            ret = ff_mpeg4_decode_picture_header(s, &gb);
+            ret = init_get_bits8(&gb, s->avctx->extradata,
+                                 s->avctx->extradata_size);
+            if (ret >= 0)
+                ret = ff_mpeg4_decode_picture_header(s, &gb);
         }
         ret = ff_mpeg4_decode_picture_header(s, &s->gb);
     } else if (CONFIG_H263I_DECODER && s->codec_id == AV_CODEC_ID_H263I) {
-- 
1.8.3.2

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