Fix issue #25 (Undefined behavior / Arithmetic overflow in bits.c)

Dutchman101 · tmatth · commit aca6801183ba · 2024-10-04T09:28:21.000-04:00
Signed-off-by: Tristan Matthews &lt;tmatth@videolan.org&gt;
diff --git a/libspeex/bits.c b/libspeex/bits.c
@@ -275,7 +275,7 @@ EXPORT int speex_bits_unpack_signed(SpeexBits *bits, int nbBits)
    /* If number is negative */
    if (d>>(nbBits-1))
    {
-      d |= (-1)<<nbBits;
+      d |= (~0u)<<nbBits;
    }
    return d;
 }

Original file line number	Diff line number	Diff line change
`@@ -275,7 +275,7 @@ EXPORT int speex_bits_unpack_signed(SpeexBits *bits, int nbBits)`
`275`	`275`	`/* If number is negative */`
`276`	`276`	`if (d>>(nbBits-1))`
`277`	`277`	`{`
`278`		`- d \|= (-1)<<nbBits;`
	`278`	`+ d \|= (~0u)<<nbBits;`
`279`	`279`	`}`
`280`	`280`	`return d;`
`281`	`281`	`}`