linux-hardening - [PATCH 6.0 0578/1073] fortify: Do not cast to "unsigned char"

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Wed, 28 Dec 2022 15:36:06 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     stable@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        patches@...ts.linux.dev,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        linux-hardening@...r.kernel.org, Kees Cook <keescook@...omium.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 6.0 0578/1073] fortify: Do not cast to "unsigned char"

From: Kees Cook <keescook@...omium.org>

[ Upstream commit e9a40e1585d792751d3a122392695e5a53032809 ]

Do not cast to "unsigned char", as this needlessly creates type problems
when attempting builds without -Wno-pointer-sign[1]. The intent of the
cast is to drop possible "const" types.

[1] https://lore.kernel.org/lkml/CAHk-=wgz3Uba8w7kdXhsqR1qvfemYL+OFQdefJnkeqXG8qZ_pA@mail.gmail.com/

Suggested-by: Linus Torvalds <torvalds@...ux-foundation.org>
Fixes: 3009f891bb9f ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")
Cc: linux-hardening@...r.kernel.org
Signed-off-by: Kees Cook <keescook@...omium.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 include/linux/fortify-string.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/fortify-string.h b/include/linux/fortify-string.h
index ae076aae9e66..c26160fe2e34 100644
--- a/include/linux/fortify-string.h
+++ b/include/linux/fortify-string.h
@@ -17,7 +17,7 @@ void __write_overflow_field(size_t avail, size_t wanted) __compiletime_warning("
 
 #define __compiletime_strlen(p)					\
 ({								\
-	unsigned char *__p = (unsigned char *)(p);		\
+	char *__p = (char *)(p);				\
 	size_t __ret = SIZE_MAX;				\
 	size_t __p_size = __builtin_object_size(p, 1);		\
 	if (__p_size != SIZE_MAX &&				\
-- 
2.35.1