libavcodec/webp.c:534: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `decode_entropy_coded_image`.

libavcodec/webp.c:523:18: Call
521.     uint8_t *ct;
522. 
523.     index_size = bitstream_read(&s->bc, 8) + 1;
                      ^
524. 
525.     if (index_size <= 2)

libavcodec/bitstream.h:183:1: Parameter `bc->bits_left`
  181. 
  182. /* Return n bits from the buffer. n has to be in the 0-32 range. */
  183. static inline uint32_t bitstream_read(BitstreamContext *bc, unsigned n)
       ^
  184. {
  185.     if (!n)

libavcodec/webp.c:534:11: Call
532.         width_bits = 0;
533. 
534.     ret = decode_entropy_coded_image(s, IMAGE_ROLE_COLOR_INDEXING,
               ^
535.                                      index_size, 1);
536.     if (ret < 0)

libavcodec/webp.c:575:1: Parameter `s->bc.bits_left`
  573. }
  574. 
  575. static int decode_entropy_coded_image(WebPContext *s, enum ImageRole role,
       ^
  576.                                       int w, int h)
  577. {

libavcodec/webp.c:603:9: Call
  601.         return ret;
  602. 
  603.     if (bitstream_read_bit(&s->bc)) {
               ^
  604.         img->color_cache_bits = bitstream_read(&s->bc, 4);
  605.         if (img->color_cache_bits < 1 || img->color_cache_bits > 11) {

libavcodec/bitstream.h:145:1: Parameter `bc->bits_left`
    143. 
    144. /* Return one bit from the buffer. */
    145. static inline unsigned bitstream_read_bit(BitstreamContext *bc)
         ^
    146. {
    147.     if (!bc->bits_left)

libavcodec/bitstream.h:150:12: Call
    148.         refill_64(bc);
    149. 
    150.     return get_val(bc, 1);
                    ^
    151. }
    152. 

libavcodec/bitstream.h:130:1: <LHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `bc->bits_left`
      128. }
      129. 
      130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
           ^
      131. {
      132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: <RHS trace>
128. }
129. 
130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
     ^
131. {
132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:130:1: Parameter `n`
      128. }
      129. 
      130. static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
           ^
      131. {
      132. #ifdef BITSTREAM_READER_LE

libavcodec/bitstream.h:139:5: Binary operation: ([0, +oo] - 1):unsigned32 by call to `decode_entropy_coded_image` 
      137.     bc->bits <<= n;
      138. #endif
      139.     bc->bits_left -= n;
               ^
      140. 
      141.     return ret;
