shithub: libsamplerate

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Improve checking for possible overflow in fixed point counters.

--- a/src/src_sinc.c

+++ b/src/src_sinc.c

@@ -148,7 +148,7 @@

 int

 sinc_set_converter (SRC_PRIVATE *psrc, int src_enum)

 {	SINC_FILTER *filter, temp_filter ;

-	int count ;

+	int count, bits ;

 	/* Quick sanity check. */

 	if (SHIFT_BITS >= sizeof (increment_t) * 8 - 1)

@@ -217,9 +217,11 @@

 	sinc_reset (psrc) ;

-	count = lrint ((filter->coeff_half_len * INT_TO_FP (1)) / FP_ONE) ;

+	count = filter->coeff_half_len ;

+	for (bits = 0 ; (1 << bits) < count ; bits++)

+		count |= (1 << bits) ;

-	if (abs (count - filter->coeff_half_len) >= 1)

+	if (bits + SHIFT_BITS - 1 >= (int) (sizeof (increment_t) * 8))

 		return SRC_ERR_FILTER_LEN ;

 	return SRC_ERR_NO_ERROR ;