From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Thu, 8 May 2025 12:21:55 +0000 (+0000)
Subject: math: Fix UB in ldbl-128ibm setpayload
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fheads%2Fazanella%2Fubsan-undef;p=thirdparty%2Fglibc.git

math: Fix UB in ldbl-128ibm setpayload
---

diff --git a/sysdeps/ieee754/ldbl-128ibm/s_setpayloadl_main.c b/sysdeps/ieee754/ldbl-128ibm/s_setpayloadl_main.c
index bff6c34625..eab69228d1 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_setpayloadl_main.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_setpayloadl_main.c
@@ -42,7 +42,8 @@ FUNC (long double *x, long double payload)
   if ((lx & 0x7fffffffffffffffULL) != 0
       || exponent >= BIAS + PAYLOAD_DIG
       || (exponent < BIAS && !(SET_HIGH_BIT && hx == 0))
-      || (hx & ((1ULL << (BIAS + EXPLICIT_MANT_DIG - exponent)) - 1)) != 0)
+      || ((BIAS + EXPLICIT_MANT_DIG - exponent <= 64)
+	  && ((hx & ((1ULL << (BIAS + EXPLICIT_MANT_DIG - exponent)) - 1)) != 0)))
     {
       *x = 0.0L;
       return 1;