[PATCH 3.12 105/119] score: fix copy_from_user() and friends
From: Jiri Slaby <hidden>
Date: 2016-09-29 10:33:59
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Al Viro <viro@zeniv.linux.org.uk> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit b615e3c74621e06cd97f86373ca90d43d6d998aa upstream. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jiri Slaby <redacted> --- arch/score/include/asm/uaccess.h | 41 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 21 deletions(-)
diff --git a/arch/score/include/asm/uaccess.h b/arch/score/include/asm/uaccess.h
index c882d961e5b8..69326dfb894d 100644
--- a/arch/score/include/asm/uaccess.h
+++ b/arch/score/include/asm/uaccess.h@@ -296,35 +296,34 @@ extern int __copy_tofrom_user(void *to, const void *from, unsigned long len); static inline unsigned long copy_from_user(void *to, const void *from, unsigned long len) { - unsigned long over; + unsigned long res = len; - if (access_ok(VERIFY_READ, from, len)) - return __copy_tofrom_user(to, from, len); + if (likely(access_ok(VERIFY_READ, from, len))) + res = __copy_tofrom_user(to, from, len); - if ((unsigned long)from < TASK_SIZE) { - over = (unsigned long)from + len - TASK_SIZE; - return __copy_tofrom_user(to, from, len - over) + over; - } - return len; + if (unlikely(res)) + memset(to + (len - res), 0, res); + + return res; } static inline unsigned long copy_to_user(void *to, const void *from, unsigned long len) { - unsigned long over; - - if (access_ok(VERIFY_WRITE, to, len)) - return __copy_tofrom_user(to, from, len); + if (likely(access_ok(VERIFY_WRITE, to, len))) + len = __copy_tofrom_user(to, from, len); - if ((unsigned long)to < TASK_SIZE) { - over = (unsigned long)to + len - TASK_SIZE; - return __copy_tofrom_user(to, from, len - over) + over; - } return len; } -#define __copy_from_user(to, from, len) \ - __copy_tofrom_user((to), (from), (len)) +static inline unsigned long +__copy_from_user(void *to, const void *from, unsigned long len) +{ + unsigned long left = __copy_tofrom_user(to, from, len); + if (unlikely(left)) + memset(to + (len - left), 0, left); + return left; +} #define __copy_to_user(to, from, len) \ __copy_tofrom_user((to), (from), (len))
@@ -338,17 +337,17 @@ __copy_to_user_inatomic(void *to, const void *from, unsigned long len) static inline unsigned long __copy_from_user_inatomic(void *to, const void *from, unsigned long len) { - return __copy_from_user(to, from, len); + return __copy_tofrom_user(to, from, len); } -#define __copy_in_user(to, from, len) __copy_from_user(to, from, len) +#define __copy_in_user(to, from, len) __copy_tofrom_user(to, from, len) static inline unsigned long copy_in_user(void *to, const void *from, unsigned long len) { if (access_ok(VERIFY_READ, from, len) && access_ok(VERFITY_WRITE, to, len)) - return copy_from_user(to, from, len); + return __copy_tofrom_user(to, from, len); } /*
--
2.10.0