From d0cf385160c12abd109746cad1f13e3b3e8b50b8 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 9 Sep 2016 19:22:34 -0400 Subject: [PATCH] microblaze: fix copy_from_user() Cc: stable@vger.kernel.org Signed-off-by: Al Viro --- arch/microblaze/include/asm/uaccess.h | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 331b0d35f89c..3a486d3b6f52 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -373,10 +373,13 @@ extern long __user_bad(void); static inline long copy_from_user(void *to, const void __user *from, unsigned long n) { + unsigned long res = n; might_fault(); - if (access_ok(VERIFY_READ, from, n)) - return __copy_from_user(to, from, n); - return 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; } #define __copy_to_user(to, from, n) \ -- 2.20.1