diff --git a/src/mux/muxread.c b/src/mux/muxread.c

index 0b55286..eb5070b 100644

--- a/src/mux/muxread.c

+++ b/src/mux/muxread.c

@@ -187,7 +187,7 @@

   size = bitstream->size;

   if (data == NULL) return NULL;

-  if (size < RIFF_HEADER_SIZE) return NULL;

+  if (size < RIFF_HEADER_SIZE + CHUNK_HEADER_SIZE) return NULL;

   if (GetLE32(data + 0) != MKFOURCC('R', 'I', 'F', 'F') ||

       GetLE32(data + CHUNK_HEADER_SIZE) != MKFOURCC('W', 'E', 'B', 'P')) {

     return NULL;

@@ -196,8 +196,6 @@

   mux = WebPMuxNew();

   if (mux == NULL) return NULL;

-  if (size < RIFF_HEADER_SIZE + TAG_SIZE) goto Err;

-

   tag = GetLE32(data + RIFF_HEADER_SIZE);

   if (tag != kChunks[IDX_VP8].tag &&

       tag != kChunks[IDX_VP8L].tag &&

@@ -206,12 +204,11 @@

   }

   riff_size = SizeWithPadding(GetLE32(data + TAG_SIZE));

-  if (riff_size > MAX_CHUNK_PAYLOAD || riff_size > size) {

-    goto Err;

-  } else {

-    if (riff_size < size) {  // Redundant data after last chunk.

-      size = riff_size;  // To make sure we don't read any data beyond mux_size.

-    }

+  if (riff_size < CHUNK_HEADER_SIZE) goto Err;

+  if (riff_size > MAX_CHUNK_PAYLOAD || riff_size > size) goto Err;

+  // There's no point in reading past the end of the RIFF chunk.

+  if (size > riff_size + CHUNK_HEADER_SIZE) {

+    size = riff_size + CHUNK_HEADER_SIZE;

   }

   end = data + size;