From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue, 22 Apr 2025 17:28:35 +0000 (-0300)
Subject: string: Fix UB on gneric stpcpy
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=925d03df27356314d53db76709a1c3435c57598e;p=thirdparty%2Fglibc.git

string: Fix UB on gneric stpcpy

Building with ubsan it trigger:

UBSAN: Undefined behaviour in ../string/stpcpy.c:91:12 shift exponent 56 is too large for 32-bit type 'int'

Use an unsigned constant literal for MERGE, since op_t is defined
as unsigned.
---

diff --git a/string/stpcpy.c b/string/stpcpy.c
index 214802266c..0fe1b99192 100644
--- a/string/stpcpy.c
+++ b/string/stpcpy.c
@@ -88,7 +88,7 @@ stpcpy_unaligned_loop (op_t *restrict dst, const op_t *restrict src,
 	}
 
       /* Align the final partial of P2.  */
-      w2 = MERGE (w2b, sh_1, 0, sh_2);
+      w2 = MERGE (w2b, sh_1, 0UL, sh_2);
     }
 
 out: