[FFmpeg-devel] [PATCH] aac_fixed: fix overflow in sbr_sum_square_c

[Andreas Cadhalpun]

On 02.12.2015 20:58, Andreas Cadhalpun wrote:
> On 19.11.2015 01:01, Andreas Cadhalpun wrote:
>> Subject: [PATCH] sbrdsp_fixed: assert that input values for sbr_sum_square_c
>>  are valid
>>
>> Larger values can cause overflows, leading to this function returning a
>> negative value.
>>
>> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
>> ---
>>  libavcodec/sbrdsp_fixed.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/libavcodec/sbrdsp_fixed.c b/libavcodec/sbrdsp_fixed.c
>> index 5b7b7a6..f4e3de0 100644
>> --- a/libavcodec/sbrdsp_fixed.c
>> +++ b/libavcodec/sbrdsp_fixed.c
>> @@ -38,9 +38,14 @@ static SoftFloat sbr_sum_square_c(int (*x)[2], int n)
>>      int i, nz, round;
>>  
>>      for (i = 0; i < n; i += 2) {
>> +        // Larger values are inavlid and could cause overflows of accu.
>> +        av_assert2(FFABS(x[i + 0][0]) >> 29 == 0);
>>          accu += (int64_t)x[i + 0][0] * x[i + 0][0];
>> +        av_assert2(FFABS(x[i + 0][1]) >> 29 == 0);
>>          accu += (int64_t)x[i + 0][1] * x[i + 0][1];
>> +        av_assert2(FFABS(x[i + 1][0]) >> 29 == 0);
>>          accu += (int64_t)x[i + 1][0] * x[i + 1][0];
>> +        av_assert2(FFABS(x[i + 1][1]) >> 29 == 0);
>>          accu += (int64_t)x[i + 1][1] * x[i + 1][1];
>>      }
>>  
> 
> Ping.

I pushed this now.

Best regards,
Andreas