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asm-generic: {get,put}_user ptr argument evaluate only 1 time

Current implemantation ptr argument evaluate 2 times.
It'll be an unexpected result.

Changes v5:
Remove unnecessary const.
Changes v4:
Temporary pointer type change to const void*
Changes v3:
Some build error fix.
Changes v2:
Argument x protect.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
steinar/wifi_calib_4_9_kernel
Yoshinori Sato 2015-07-16 13:56:06 +09:00
parent a795239b69
commit a02613a4ba
1 changed files with 6 additions and 4 deletions

View File

@ -163,9 +163,10 @@ static inline __must_check long __copy_to_user(void __user *to,
#define put_user(x, ptr) \
({ \
void *__p = (ptr); \
might_fault(); \
access_ok(VERIFY_WRITE, ptr, sizeof(*ptr)) ? \
__put_user(x, ptr) : \
access_ok(VERIFY_WRITE, __p, sizeof(*ptr)) ? \
__put_user((x), ((__typeof__(*(ptr)) *)__p)) : \
-EFAULT; \
})
@ -225,9 +226,10 @@ extern int __put_user_bad(void) __attribute__((noreturn));
#define get_user(x, ptr) \
({ \
const void *__p = (ptr); \
might_fault(); \
access_ok(VERIFY_READ, ptr, sizeof(*ptr)) ? \
__get_user(x, ptr) : \
access_ok(VERIFY_READ, __p, sizeof(*ptr)) ? \
__get_user((x), (__typeof__(*(ptr)) *)__p) : \
-EFAULT; \
})