avcodec/siren: Check several indexes

Fixes: Multiple out of array accesses
Fixes: 20817/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SIREN_fuzzer-5754041227542528.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-03-01 00:00:25 +01:00
parent 60b1f85b67
commit 12ec8ad24b

View File

@ -428,6 +428,7 @@ static int decode_envelope(SirenContext *s, GetBitContext *gb,
int *absolute_region_power_index, int esf_adjustment)
{
absolute_region_power_index[0] = (int)get_bits(gb, 5) - esf_adjustment;
absolute_region_power_index[0] = av_clip(absolute_region_power_index[0], -24, 39);
decoder_standard_deviation[0] = s->standard_deviation[absolute_region_power_index[0] + 24];
for (int i = 1; i < number_of_regions; i++) {
@ -437,7 +438,7 @@ static int decode_envelope(SirenContext *s, GetBitContext *gb,
index = differential_decoder_tree[i - 1][index][get_bits1(gb)];
} while (index > 0);
absolute_region_power_index[i] = absolute_region_power_index[i - 1] - index - 12;
absolute_region_power_index[i] = av_clip(absolute_region_power_index[i - 1] - index - 12, -24, 39);
decoder_standard_deviation[i] = s->standard_deviation[absolute_region_power_index[i] + 24];
}
@ -500,6 +501,8 @@ static int categorize_regions(int number_of_regions, int number_of_available_bit
}
}
}
if (raw_value == -99)
return AVERROR_INVALIDDATA;
*min_rate_ptr++ = raw_min_idx;
min +=
expected_bits_table[min_rate_categories[raw_min_idx] + 1] -
@ -518,6 +521,8 @@ static int categorize_regions(int number_of_regions, int number_of_available_bit
}
}
}
if (raw_value == 99)
return AVERROR_INVALIDDATA;
*--max_rate_ptr = raw_max_idx;
max += expected_bits_table[max_rate_categories[raw_max_idx] - 1] -
@ -684,9 +689,11 @@ static int siren_decode(AVCodecContext *avctx, void *data,
rate_control = get_bits(gb, 4);
categorize_regions(s->number_of_regions, get_bits_left(gb),
s->absolute_region_power_index, s->power_categories,
s->category_balance);
ret = categorize_regions(s->number_of_regions, get_bits_left(gb),
s->absolute_region_power_index, s->power_categories,
s->category_balance);
if (ret < 0)
return ret;
for (int i = 0; i < rate_control; i++)
s->power_categories[s->category_balance[i]]++;