res/res_rtp_asterisk.c: Fixing possible divide by zero

Currently, when the Asterisk calculates rtp statistics, it uses
sample_count as a unsigned integer parameter. This would be fine
for most of cases, but in case of large enough number of sample_count,
this might be causing the divide by zero error.

ASTERISK-28321

Change-Id: If7e0629abaceddd2166eb012456c53033ea26249
This commit is contained in:
sungtae kim
2019-03-03 16:20:24 +01:00
committed by Joshua C. Colp
parent 255e374254
commit ca8f254f0f

View File

@@ -3075,6 +3075,14 @@ static double normdev_compute(double normdev, double sample, unsigned int sample
normdev = normdev * sample_count + sample;
sample_count++;
/*
It's possible the sample_count hits the maximum value and back to 0.
Set to 1 to prevent the divide by zero crash if the sample_count is 0.
*/
if (sample_count == 0) {
sample_count = 1;
}
return normdev / sample_count;
}
@@ -3091,6 +3099,14 @@ static double stddev_compute(double stddev, double sample, double normdev, doubl
stddev = sample_count * stddev;
sample_count++;
/*
It's possible the sample_count hits the maximum value and back to 0.
Set to 1 to prevent the divide by zero crash if the sample_count is 0.
*/
if (sample_count == 0) {
sample_count = 1;
}
return stddev +
( sample_count * SQUARE( (sample - normdev) / sample_count ) ) +
( SQUARE(sample - normdev_curent) / sample_count );