lzw: prevent buffer overreads.

[ffmpeg] / libavcodec / mpeg12.c

diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index da4dd2c1703e6e8f7c0ff023fb921e934a9161d3..c49343f4b2b166efcec413268aff276b82c7eca0 100644 (file)
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -1117,7 +1117,7 @@ static av_cold int mpeg_decode_init(AVCodecContext *avctx)
     for (i = 0; i < 64; i++)
        s2->dsp.idct_permutation[i]=i;
 
-    MPV_decode_defaults(s2);
+    ff_MPV_decode_defaults(s2);
 
     s->mpeg_enc_ctx.avctx  = avctx;
     s->mpeg_enc_ctx.flags  = avctx->flags;
@@ -1219,7 +1219,7 @@ static int mpeg_decode_postinit(AVCodecContext *avctx)
         if (s1->mpeg_enc_ctx_allocated) {
             ParseContext pc = s->parse_context;
             s->parse_context.buffer = 0;
-            MPV_common_end(s);
+            ff_MPV_common_end(s);
             s->parse_context = pc;
         }
 
@@ -1237,7 +1237,6 @@ static int mpeg_decode_postinit(AVCodecContext *avctx)
          * that behave like P-frames. */
         avctx->has_b_frames = !s->low_delay;
 
-        assert((avctx->sub_id == 1) == (avctx->codec_id == CODEC_ID_MPEG1VIDEO));
         if (avctx->codec_id == CODEC_ID_MPEG1VIDEO) {
             //MPEG-1 fps
             avctx->time_base.den = avpriv_frame_rate_tab[s->frame_rate_index].num;
@@ -1298,7 +1297,7 @@ static int mpeg_decode_postinit(AVCodecContext *avctx)
          * if DCT permutation is changed. */
         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
 
-        if (MPV_common_init(s) < 0)
+        if (ff_MPV_common_init(s) < 0)
             return -2;
 
         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
@@ -1382,7 +1381,6 @@ static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
 
     av_dlog(s->avctx, "sequence extension\n");
     s->codec_id      = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
-    s->avctx->sub_id = 2; /* indicates MPEG-2 found */
 
     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
@@ -1563,7 +1561,7 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
 
     /* start frame decoding */
     if (s->first_field || s->picture_structure == PICT_FRAME) {
-        if (MPV_frame_start(s, avctx) < 0)
+        if (ff_MPV_frame_start(s, avctx) < 0)
             return -1;
 
         ff_er_frame_start(s);
@@ -1753,13 +1751,13 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
 
-        MPV_decode_mb(s, s->block);
+        ff_MPV_decode_mb(s, s->block);
 
         if (++s->mb_x >= s->mb_width) {
             const int mb_size = 16 >> s->avctx->lowres;
 
             ff_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
-            MPV_report_decode_progress(s);
+            ff_MPV_report_decode_progress(s);
 
             s->mb_x = 0;
             s->mb_y += 1 << field_pic;
@@ -1912,10 +1910,10 @@ static int slice_end(AVCodecContext *avctx, AVFrame *pict)
 
         ff_er_frame_end(s);
 
-        MPV_frame_end(s);
+        ff_MPV_frame_end(s);
 
         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
-            *pict = *(AVFrame*)s->current_picture_ptr;
+            *pict = s->current_picture_ptr->f;
             ff_print_debug_info(s, pict);
         } else {
             if (avctx->active_thread_type & FF_THREAD_FRAME)
@@ -1923,7 +1921,7 @@ static int slice_end(AVCodecContext *avctx, AVFrame *pict)
             /* latency of 1 frame for I- and P-frames */
             /* XXX: use another variable than picture_number */
             if (s->last_picture_ptr != NULL) {
-                *pict = *(AVFrame*)s->last_picture_ptr;
+                *pict = s->last_picture_ptr->f;
                  ff_print_debug_info(s, pict);
             }
         }
@@ -2000,7 +1998,6 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
     s->frame_pred_frame_dct = 1;
     s->chroma_format        = 1;
     s->codec_id             = s->avctx->codec_id = CODEC_ID_MPEG1VIDEO;
-    avctx->sub_id           = 1; /* indicates MPEG-1 */
     s->out_format           = FMT_MPEG1;
     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
     if (s->flags & CODEC_FLAG_LOW_DELAY)
@@ -2022,7 +2019,7 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
     /* start new MPEG-1 context decoding */
     s->out_format = FMT_MPEG1;
     if (s1->mpeg_enc_ctx_allocated) {
-        MPV_common_end(s);
+        ff_MPV_common_end(s);
     }
     s->width  = avctx->coded_width;
     s->height = avctx->coded_height;
@@ -2037,7 +2034,7 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
         if (avctx->idct_algo == FF_IDCT_AUTO)
             avctx->idct_algo = FF_IDCT_SIMPLE;
 
-    if (MPV_common_init(s) < 0)
+    if (ff_MPV_common_init(s) < 0)
         return -1;
     exchange_uv(s); // common init reset pblocks, so we swap them here
     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
@@ -2060,7 +2057,6 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
     s->frame_pred_frame_dct  = 1;
     s->chroma_format         = 1;
     s->codec_id              = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
-    avctx->sub_id            = 2; /* indicates MPEG-2 */
     s1->save_width           = s->width;
     s1->save_height          = s->height;
     s1->save_progressive_seq = s->progressive_sequence;
@@ -2203,7 +2199,7 @@ static int mpeg_decode_frame(AVCodecContext *avctx,
     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
         /* special case for last picture */
         if (s2->low_delay == 0 && s2->next_picture_ptr) {
-            *picture = *(AVFrame*)s2->next_picture_ptr;
+            *picture = s2->next_picture_ptr->f;
             s2->next_picture_ptr = NULL;
 
             *data_size = sizeof(AVFrame);
@@ -2478,7 +2474,7 @@ static int mpeg_decode_end(AVCodecContext *avctx)
     Mpeg1Context *s = avctx->priv_data;
 
     if (s->mpeg_enc_ctx_allocated)
-        MPV_common_end(&s->mpeg_enc_ctx);
+        ff_MPV_common_end(&s->mpeg_enc_ctx);
     return 0;
 }