From 35fdfe62a4ff471074ca53b7626ec80e83d244bd Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Fri, 20 Jan 2023 11:37:39 +0100 Subject: math: fix undefined shift in logf A signed int shift overflowed when computing a constant mask, use hex literal instead. This is unlikely to cause actual issues unless the code was compiled with ubsan or similar instrumentation specifically to catch this. The stripped libc.so is unchanged on x86_64. Reported by q66 on irc. --- src/math/logf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src') diff --git a/src/math/logf.c b/src/math/logf.c index 7ee5d7fe..e4c2237c 100644 --- a/src/math/logf.c +++ b/src/math/logf.c @@ -53,7 +53,7 @@ float logf(float x) tmp = ix - OFF; i = (tmp >> (23 - LOGF_TABLE_BITS)) % N; k = (int32_t)tmp >> 23; /* arithmetic shift */ - iz = ix - (tmp & 0x1ff << 23); + iz = ix - (tmp & 0xff800000); invc = T[i].invc; logc = T[i].logc; z = (double_t)asfloat(iz); -- cgit v1.2.1