From 536e7d5ea02825c12e64356149a1f4c6691efd7b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 17 Aug 2016 16:02:32 -0400 Subject: [PATCH] alpha: fix copy_from_user() commit 2561d309dfd1555e781484af757ed0115035ddb3 upstream. it should clear the destination even when access_ok() fails. Signed-off-by: Al Viro [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- arch/alpha/include/asm/uaccess.h | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/arch/alpha/include/asm/uaccess.h b/arch/alpha/include/asm/uaccess.h index b49ec2f8d6e3..3cd61320e024 100644 --- a/arch/alpha/include/asm/uaccess.h +++ b/arch/alpha/include/asm/uaccess.h @@ -371,14 +371,6 @@ __copy_tofrom_user_nocheck(void *to, const void *from, long len) return __cu_len; } -extern inline long -__copy_tofrom_user(void *to, const void *from, long len, const void __user *validate) -{ - if (__access_ok((unsigned long)validate, len, get_fs())) - len = __copy_tofrom_user_nocheck(to, from, len); - return len; -} - #define __copy_to_user(to,from,n) \ ({ \ __chk_user_ptr(to); \ @@ -393,17 +385,22 @@ __copy_tofrom_user(void *to, const void *from, long len, const void __user *vali #define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user - extern inline long copy_to_user(void __user *to, const void *from, long n) { - return __copy_tofrom_user((__force void *)to, from, n, to); + if (likely(__access_ok((unsigned long)to, n, get_fs()))) + n = __copy_tofrom_user_nocheck((__force void *)to, from, n); + return n; } extern inline long copy_from_user(void *to, const void __user *from, long n) { - return __copy_tofrom_user(to, (__force void *)from, n, from); + if (likely(__access_ok((unsigned long)from, n, get_fs()))) + n = __copy_tofrom_user_nocheck(to, (__force void *)from, n); + else + memset(to, 0, n); + return n; } extern void __do_clear_user(void); -- 2.30.2