1 files changed, 14 insertions, 48 deletions

diff --git a/arch/x86/include/asm/uaccess_32.h b/arch/x86/include/asm/uaccess_32.h
index f5dcb5204dcd..7d3bdd1ed697 100644
--- a/arch/x86/include/asm/uaccess_32.h
+++ b/arch/x86/include/asm/uaccess_32.h
@@ -33,38 +33,11 @@ unsigned long __must_check __copy_from_user_ll_nocache_nozero
  * the specified block with access_ok() before calling this function.
  * The caller should also make sure he pins the user space address
  * so that we don't result in page fault and sleep.
- *
- * Here we special-case 1, 2 and 4-byte copy_*_user invocations.  On a fault
- * we return the initial request size (1, 2 or 4), as copy_*_user should do.
- * If a store crosses a page boundary and gets a fault, the x86 will not write
- * anything, so this is accurate.
  */
-
 static __always_inline unsigned long __must_check
 __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
 {
-	if (__builtin_constant_p(n)) {
-		unsigned long ret;
-
-		switch (n) {
-		case 1:
-			__put_user_size(*(u8 *)from, (u8 __user *)to,
-					1, ret, 1);
-			return ret;
-		case 2:
-			__put_user_size(*(u16 *)from, (u16 __user *)to,
-					2, ret, 2);
-			return ret;
-		case 4:
-			__put_user_size(*(u32 *)from, (u32 __user *)to,
-					4, ret, 4);
-			return ret;
-		case 8:
-			__put_user_size(*(u64 *)from, (u64 __user *)to,
-					8, ret, 8);
-			return ret;
-		}
-	}
+	check_object_size(from, n, true);
 	return __copy_to_user_ll(to, from, n);
 }
 
@@ -93,26 +66,6 @@ __copy_to_user(void __user *to, const void *from, unsigned long n)
 static __always_inline unsigned long
 __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
 {
-	/* Avoid zeroing the tail if the copy fails..
-	 * If 'n' is constant and 1, 2, or 4, we do still zero on a failure,
-	 * but as the zeroing behaviour is only significant when n is not
-	 * constant, that shouldn't be a problem.
-	 */
-	if (__builtin_constant_p(n)) {
-		unsigned long ret;
-
-		switch (n) {
-		case 1:
-			__get_user_size(*(u8 *)to, from, 1, ret, 1);
-			return ret;
-		case 2:
-			__get_user_size(*(u16 *)to, from, 2, ret, 2);
-			return ret;
-		case 4:
-			__get_user_size(*(u32 *)to, from, 4, ret, 4);
-			return ret;
-		}
-	}
 	return __copy_from_user_ll_nozero(to, from, n);
 }
 
@@ -143,18 +96,25 @@ static __always_inline unsigned long
 __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
 	might_fault();
+	check_object_size(to, n, false);
 	if (__builtin_constant_p(n)) {
 		unsigned long ret;
 
 		switch (n) {
 		case 1:
+			__uaccess_begin();
 			__get_user_size(*(u8 *)to, from, 1, ret, 1);
+			__uaccess_end();
 			return ret;
 		case 2:
+			__uaccess_begin();
 			__get_user_size(*(u16 *)to, from, 2, ret, 2);
+			__uaccess_end();
 			return ret;
 		case 4:
+			__uaccess_begin();
 			__get_user_size(*(u32 *)to, from, 4, ret, 4);
+			__uaccess_end();
 			return ret;
 		}
 	}
@@ -170,13 +130,19 @@ static __always_inline unsigned long __copy_from_user_nocache(void *to,
 
 		switch (n) {
 		case 1:
+			__uaccess_begin();
 			__get_user_size(*(u8 *)to, from, 1, ret, 1);
+			__uaccess_end();
 			return ret;
 		case 2:
+			__uaccess_begin();
 			__get_user_size(*(u16 *)to, from, 2, ret, 2);
+			__uaccess_end();
 			return ret;
 		case 4:
+			__uaccess_begin();
 			__get_user_size(*(u32 *)to, from, 4, ret, 4);
+			__uaccess_end();
 			return ret;
 		}
 	}