Merge commit '24a36256'

* commit '24a36256':
  buffer: fix av_buffer_realloc() when the data is offset wrt buffer start
Merged-by: Clément Bœsch <u@pkh.me>

libavutil/buffer.c

@@ -191,7 +191,7 @@ int av_buffer_realloc(AVBufferRef **pbuf, int size)
         return 0;
 
     if (!(buf->buffer->flags & BUFFER_FLAG_REALLOCATABLE) ||
-        !av_buffer_is_writable(buf)) {
+        !av_buffer_is_writable(buf) || buf->data != buf->buffer->data) {
         /* cannot realloc, allocate a new reallocable buffer and copy data */
         AVBufferRef *new = NULL;