Merge commit '993977032a0adb47eb70e7fef6ce0d5370027e83' into release/0.10

* commit '993977032a0adb47eb70e7fef6ce0d5370027e83':
  xan: Use bytestream2 to limit reading to within the buffer
  pcx: Consume the whole packet if giving up due to missing palette
  pngdec: Stop trying to decode once inflate returns Z_STREAM_END
  mov: Make sure the read sample count is nonnegative
  bfi: Add some very basic sanity checks for input packet sizes

Conflicts:
	libavformat/mov.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>

3 files changed, 15 insertions, 12 deletions

diff --git a/libavcodec/pcx.c b/libavcodec/pcx.c
index b23a0a8d51..7c98bfa4f9 100644
--- a/libavcodec/pcx.c
+++ b/libavcodec/pcx.c
@@ -195,6 +195,7 @@ static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
         }
         if (*buf++ != 12) {
             av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
+            ret = buf_size;
             goto end;
         }
 
diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 5a76918e29..1edef54035 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -378,6 +378,10 @@ static int png_decode_idat(PNGDecContext *s, int length)
             s->zstream.avail_out = s->crow_size;
             s->zstream.next_out = s->crow_buf;
         }
+        if (ret == Z_STREAM_END && s->zstream.avail_in > 0) {
+            av_log(NULL, AV_LOG_WARNING, "%d undecompressed bytes left in buffer\n", s->zstream.avail_in);
+            return 0;
+        }
     }
     return 0;
 }
diff --git a/libavcodec/xan.c b/libavcodec/xan.c
index 62bec83490..4afc087c32 100644
--- a/libavcodec/xan.c
+++ b/libavcodec/xan.c
@@ -285,8 +285,8 @@ static int xan_wc3_decode_frame(XanContext *s) {
 
     /* pointers to segments inside the compressed chunk */
     const unsigned char *huffman_segment;
-    const unsigned char *size_segment;
-    const unsigned char *vector_segment;
+    GetByteContext       size_segment;
+    GetByteContext       vector_segment;
     const unsigned char *imagedata_segment;
     int huffman_offset, size_offset, vector_offset, imagedata_offset,
         imagedata_size;
@@ -306,8 +306,8 @@ static int xan_wc3_decode_frame(XanContext *s) {
         return AVERROR_INVALIDDATA;
 
     huffman_segment   = s->buf + huffman_offset;
-    size_segment      = s->buf + size_offset;
-    vector_segment    = s->buf + vector_offset;
+    bytestream2_init(&size_segment,   s->buf + size_offset,   s->size - size_offset);
+    bytestream2_init(&vector_segment, s->buf + vector_offset, s->size - vector_offset);
     imagedata_segment = s->buf + imagedata_offset;
 
     if (xan_huffman_decode(opcode_buffer, opcode_buffer_size,
@@ -359,19 +359,17 @@ static int xan_wc3_decode_frame(XanContext *s) {
 
         case 9:
         case 19:
-            size = *size_segment++;
+            size = bytestream2_get_byte(&size_segment);
             break;
 
         case 10:
         case 20:
-            size = AV_RB16(&size_segment[0]);
-            size_segment += 2;
+            size = bytestream2_get_be16(&size_segment);
             break;
 
         case 11:
         case 21:
-            size = AV_RB24(size_segment);
-            size_segment += 3;
+            size = bytestream2_get_be24(&size_segment);
             break;
         }
 
@@ -393,9 +391,9 @@ static int xan_wc3_decode_frame(XanContext *s) {
             }
         } else {
             /* run-based motion compensation from last frame */
-            motion_x = sign_extend(*vector_segment >> 4,  4);
-            motion_y = sign_extend(*vector_segment & 0xF, 4);
-            vector_segment++;
+            uint8_t vector = bytestream2_get_byte(&vector_segment);
+            motion_x = sign_extend(vector >> 4,  4);
+            motion_y = sign_extend(vector & 0xF, 4);
 
             /* copy a run of pixels from the previous frame */
             xan_wc3_copy_pixel_run(s, x, y, size, motion_x, motion_y);