From 2fac6f3fec2303649e9cd572255776cb93d3f888 Mon Sep 17 00:00:00 2001 From: Deepak Saxena Date: Mon, 25 Apr 2005 23:40:05 +0100 Subject: [PATCH] ARM: 2653/1: Fix memset and memzero macro double-reference of parameters Patch from Deepak Saxena The current memset() and memzero() macros on ARM reference the incoming parameters more than once and this can cause uninted side-effects. The issue was found while debugging SCTP protocol and with the specific usage of memzero(skb_put(skb,size),size). This call would call skb_put(skb,size) twice leading to badness. The fixed version copies the incoming parameters into local variables and uses those instead. Signed-off-by: Deepak Saxena Signed-off-by: Russell King --- include/asm-arm/string.h | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'include/asm-arm/string.h') diff --git a/include/asm-arm/string.h b/include/asm-arm/string.h index 2a8ab162412f..e50c4a39b699 100644 --- a/include/asm-arm/string.h +++ b/include/asm-arm/string.h @@ -29,15 +29,22 @@ extern void __memzero(void *ptr, __kernel_size_t n); #define memset(p,v,n) \ ({ \ - if ((n) != 0) { \ + void *__p = (p); size_t __n = n; \ + if ((__n) != 0) { \ if (__builtin_constant_p((v)) && (v) == 0) \ - __memzero((p),(n)); \ + __memzero((__p),(__n)); \ else \ - memset((p),(v),(n)); \ + memset((__p),(v),(__n)); \ } \ - (p); \ + (__p); \ }) -#define memzero(p,n) ({ if ((n) != 0) __memzero((p),(n)); (p); }) +#define memzero(p,n) \ + ({ \ + void *__p = (p); size_t __n = n; \ + if ((__n) != 0) \ + __memzero((__p),(__n)); \ + (__p); \ + }) #endif -- cgit v1.2.3-59-g8ed1b