avcodec/mv30: Fix multiple integer overflows

Fixes: signed integer overflow: -895002 * 2400 cannot be represented in type 'int'
Fixes: 26052/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MV30_fuzzer-5431812577558528

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-10-04 19:28:47 +02:00
parent 42ded4d1e6
commit 77cdc68479

View File

@ -198,12 +198,12 @@ static void idct_add(uint8_t *dst, int stride,
static inline void idct2_1d(int *blk, int step)
{
const int t0 = blk[0 * step];
const int t1 = blk[1 * step];
const int t2 = (int)(t1 * 473U) >> 8;
const int t3 = t2 - t1;
const int t4 = ((int)(t1 * 362U) >> 8) - t3;
const int t5 = (((int)(t1 * 277U) >> 8) - t2) + t4;
const unsigned int t0 = blk[0 * step];
const unsigned int t1 = blk[1 * step];
const unsigned int t2 = (int)(t1 * 473U) >> 8;
const unsigned int t3 = t2 - t1;
const unsigned int t4 = ((int)(t1 * 362U) >> 8) - t3;
const unsigned int t5 = (((int)(t1 * 277U) >> 8) - t2) + t4;
blk[0 * step] = t1 + t0;
blk[1 * step] = t0 + t3;
@ -305,14 +305,14 @@ static int decode_intra_block(AVCodecContext *avctx, int mode,
case 1:
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = ((pfill[0] * qtab[0]) >> 5) + 128;
block[0] = ((int)((unsigned)pfill[0] * qtab[0]) >> 5) + 128;
s->bdsp.fill_block_tab[1](dst, block[0], linesize, 8);
break;
case 2:
memset(block, 0, sizeof(*block) * 64);
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = pfill[0] * qtab[0];
block[0] = (unsigned)pfill[0] * qtab[0];
block[1] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[1];
block[8] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[8];
block[9] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[9];
@ -321,7 +321,7 @@ static int decode_intra_block(AVCodecContext *avctx, int mode,
case 3:
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = pfill[0] * qtab[0];
block[0] = (unsigned)pfill[0] * qtab[0];
for (int i = 1; i < 64; i++)
block[zigzag[i]] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[zigzag[i]];
idct_put(dst, linesize, block);
@ -346,14 +346,14 @@ static int decode_inter_block(AVCodecContext *avctx, int mode,
case 1:
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = (pfill[0] * qtab[0]) >> 5;
block[0] = (int)((unsigned)pfill[0] * qtab[0]) >> 5;
update_inter_block(dst, linesize, src, in_linesize, block[0]);
break;
case 2:
memset(block, 0, sizeof(*block) * 64);
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = pfill[0] * qtab[0];
block[0] = (unsigned)pfill[0] * qtab[0];
block[1] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[1];
block[8] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[8];
block[9] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[9];
@ -362,7 +362,7 @@ static int decode_inter_block(AVCodecContext *avctx, int mode,
case 3:
fill = sign_extend(bytestream2_get_ne16(gbyte), 16);
pfill[0] += fill;
block[0] = pfill[0] * qtab[0];
block[0] = (unsigned)pfill[0] * qtab[0];
for (int i = 1; i < 64; i++)
block[zigzag[i]] = sign_extend(bytestream2_get_ne16(gbyte), 16) * qtab[zigzag[i]];
idct_add(dst, linesize, src, in_linesize, block);