From 91344493b7da9487a8dbc1109d7486e51c8e5235 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 10 Sep 2016 16:44:03 -0400 Subject: arm: don't zero in __copy_from_user_inatomic()/__copy_from_user() adjust copy_from_user(), obviously Signed-off-by: Al Viro --- arch/arm/include/asm/uaccess.h | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index a93c0f99acf7..1f59ea051bab 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -533,11 +533,12 @@ __clear_user(void __user *addr, unsigned long n) static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) { - if (access_ok(VERIFY_READ, from, n)) - n = __copy_from_user(to, from, n); - else /* security hole - plug it */ - memset(to, 0, n); - return n; + unsigned long res = n; + if (likely(access_ok(VERIFY_READ, from, n))) + res = __copy_from_user(to, from, n); + if (unlikely(res)) + memset(to + (n - res), 0, res); + return res; } static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n) -- cgit v1.2.3-59-g8ed1b