From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Fri, 18 Apr 2025 12:40:51 +0000 (-0300)
Subject: locale: Fix UB in elem_hash
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8e44f1e0b6662e6c805945dcfcd3acbff5f0ba69;p=thirdparty%2Fglibc.git

locale: Fix UB in elem_hash

The ubsan triggers:

UBSAN: Undefined behaviour in ./elem-hash.h:27:14 left shift of 360447856 by 3 cannot be represented in type 'int'

Using unsigned shift here zero fill like signed.
---

diff --git a/locale/elem-hash.h b/locale/elem-hash.h
index 5d34ec43f3..8052b0fe6d 100644
--- a/locale/elem-hash.h
+++ b/locale/elem-hash.h
@@ -24,7 +24,7 @@ elem_hash (const char *str, int32_t n)
 
   while (n-- > 0)
     {
-      result <<= 3;
+      result = (uint32_t)result << 3;
       result += *str++;
     }