From 42641042c10c757fe10cc09088cf3f436cec5007 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Mon, 27 Sep 2021 14:13:57 +0200
Subject: [PATCH] cb710: avoid NULL pointer subtraction
Git-commit: 42641042c10c757fe10cc09088cf3f436cec5007
Patch-mainline: v5.15-rc6
References: git-fixes stable-5.14.14
clang-14 complains about an unusual way of converting a pointer to
an integer:
drivers/misc/cb710/sgbuf2.c:50:15: error: performing pointer subtraction with a null pointer has undefined behavior [-Werror,-Wnull-pointer-subtraction]
return ((ptr - NULL) & 3) != 0;
Replace this with a normal cast to uintptr_t.
Fixes: 5f5bac8272be ("mmc: Driver for CB710/720 memory card reader (MMC part)")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210927121408.939246-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/misc/cb710/sgbuf2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/misc/cb710/sgbuf2.c b/drivers/misc/cb710/sgbuf2.c
index e5a4ed3701eb..a798fad5f03c 100644
--- a/drivers/misc/cb710/sgbuf2.c
+++ b/drivers/misc/cb710/sgbuf2.c
@@ -47,7 +47,7 @@ static inline bool needs_unaligned_copy(const void *ptr)
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
return false;
#else
- return ((ptr - NULL) & 3) != 0;
+ return ((uintptr_t)ptr & 3) != 0;
#endif
}
--
2.26.2