diff options
| author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-07-30 22:40:48 -0400 |
|---|---|---|
| committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-08-17 16:04:00 -0400 |
| commit | 8ab3e80ec46e8f811c5f880890488029261dea70 (patch) | |
| tree | 6673bbdfe9392b6000314e10fabd941db7e67005 | |
| parent | 18335e8e4d6ddb289b31d8a4a362f5e15c24ff0a (diff) | |
| download | opus-8ab3e80ec46e8f811c5f880890488029261dea70.tar.gz | |
Fixes an overflow in LPC_inverse_pred_gain_QA()
We now declare that anything that would overflow is not stable enough
| -rw-r--r-- | silk/LPC_inv_pred_gain.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/silk/LPC_inv_pred_gain.c b/silk/LPC_inv_pred_gain.c index 257b28fd..87d9a499 100644 --- a/silk/LPC_inv_pred_gain.c +++ b/silk/LPC_inv_pred_gain.c @@ -77,10 +77,21 @@ static opus_int32 LPC_inverse_pred_gain_QA( /* O Returns inver /* Update AR coefficient */ for( n = 0; n < (k + 1) >> 1; n++ ) { + opus_int64 tmp64; tmp1 = A_QA[ n ]; tmp2 = A_QA[ k - n - 1 ]; - A_QA[ n ] = MUL32_FRAC_Q( tmp1 - MUL32_FRAC_Q( tmp2, rc_Q31, 31 ), rc_mult2, mult2Q ); - A_QA[ k - n - 1 ] = MUL32_FRAC_Q( tmp2 - MUL32_FRAC_Q( tmp1, rc_Q31, 31 ), rc_mult2, mult2Q ); + tmp64 = silk_RSHIFT_ROUND64( silk_SMULL( silk_SUB_SAT32(tmp1, + MUL32_FRAC_Q( tmp2, rc_Q31, 31 ) ), rc_mult2 ), mult2Q); + if( tmp64 > silk_int32_MAX || tmp64 < silk_int32_MIN ) { + return 0; + } + A_QA[ n ] = ( opus_int32 )tmp64; + tmp64 = silk_RSHIFT_ROUND64( silk_SMULL( silk_SUB_SAT32(tmp2, + MUL32_FRAC_Q( tmp1, rc_Q31, 31 ) ), rc_mult2), mult2Q); + if( tmp64 > silk_int32_MAX || tmp64 < silk_int32_MIN ) { + return 0; + } + A_QA[ k - n - 1 ] = ( opus_int32 )tmp64; } } |