From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Subject: sh: use generic strncpy()
Current SH will get below warning at strncpy()
In file included from ${LINUX}/arch/sh/include/asm/string.h:3,
from ${LINUX}/include/linux/string.h:20,
from ${LINUX}/include/linux/bitmap.h:9,
from ${LINUX}/include/linux/nodemask.h:95,
from ${LINUX}/include/linux/mmzone.h:17,
from ${LINUX}/include/linux/gfp.h:6,
from ${LINUX}/innclude/linux/slab.h:15,
from ${LINUX}/linux/drivers/mmc/host/vub300.c:38:
${LINUX}/drivers/mmc/host/vub300.c: In function 'new_system_port_status':
${LINUX}/arch/sh/include/asm/string_32.h:51:42: warning: array subscript\
80 is above array bounds of 'char[26]' [-Warray-bounds]
: "0" (__dest), "1" (__src), "r" (__src+__n)
~~~~~^~~~
In general, strncpy() should behave like below.
char dest[10];
char *src = "12345";
strncpy(dest, src, 10);
// dest = {'1', '2', '3', '4', '5',
'\0','\0','\0','\0','\0'}
But, current SH strnpy() has 2 issues.
1st is it will access to out-of-memory (= src + 10).
2nd is it needs big fixup for it, and maintenance __asm__
code is difficult.
To solve these issues, this patch simply uses generic strncpy()
instead of architecture specific one.
Link: https://marc.info/?l=linux-renesas-soc&m=157664657013309
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Cc: Alan Modra <amodra@xxxxxxxxx>
Cc: Bin Meng <bin.meng@xxxxxxxxxxxxx>
Cc: Chen Zhou <chenzhou10@xxxxxxxxxx>
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Romain Naour <romain.naour@xxxxxxxxx>
Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/sh/include/asm/string_32.h | 26 --------------------------
1 file changed, 26 deletions(-)
--- a/arch/sh/include/asm/string_32.h~sh-use-generic-strncpy
+++ a/arch/sh/include/asm/string_32.h
@@ -28,32 +28,6 @@ static inline char *strcpy(char *__dest,
return __xdest;
}
-#define __HAVE_ARCH_STRNCPY
-static inline char *strncpy(char *__dest, const char *__src, size_t __n)
-{
- register char *__xdest = __dest;
- unsigned long __dummy;
-
- if (__n == 0)
- return __xdest;
-
- __asm__ __volatile__(
- "1:\n"
- "mov.b @%1+, %2\n\t"
- "mov.b %2, @%0\n\t"
- "cmp/eq #0, %2\n\t"
- "bt/s 2f\n\t"
- " cmp/eq %5,%1\n\t"
- "bf/s 1b\n\t"
- " add #1, %0\n"
- "2:"
- : "=r" (__dest), "=r" (__src), "=&z" (__dummy)
- : "0" (__dest), "1" (__src), "r" (__src+__n)
- : "memory", "t");
-
- return __xdest;
-}
-
#define __HAVE_ARCH_STRCMP
static inline int strcmp(const char *__cs, const char *__ct)
{
_
