1 files changed, 15 insertions, 78 deletions

diff --git a/arch/powerpc/lib/checksum_wrappers.c b/arch/powerpc/lib/checksum_wrappers.c
index a0cb63fb76a1..1a14c8780278 100644
--- a/arch/powerpc/lib/checksum_wrappers.c
+++ b/arch/powerpc/lib/checksum_wrappers.c
@@ -1,17 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  *
  * Copyright (C) IBM Corporation, 2010
  *
@@ -24,79 +12,28 @@
 #include <linux/uaccess.h>
 
 __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-			       int len, __wsum sum, int *err_ptr)
+			       int len)
 {
-	unsigned int csum;
-
-	might_sleep();
-
-	*err_ptr = 0;
-
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
-
-	if (unlikely((len < 0) || !access_ok(VERIFY_READ, src, len))) {
-		*err_ptr = -EFAULT;
-		csum = (__force unsigned int)sum;
-		goto out;
-	}
-
-	csum = csum_partial_copy_generic((void __force *)src, dst,
-					 len, sum, err_ptr, NULL);
+	__wsum csum;
 
-	if (unlikely(*err_ptr)) {
-		int missing = __copy_from_user(dst, src, len);
+	if (unlikely(!user_read_access_begin(src, len)))
+		return 0;
 
-		if (missing) {
-			memset(dst + len - missing, 0, missing);
-			*err_ptr = -EFAULT;
-		} else {
-			*err_ptr = 0;
-		}
+	csum = csum_partial_copy_generic((void __force *)src, dst, len);
 
-		csum = csum_partial(dst, len, sum);
-	}
-
-out:
-	return (__force __wsum)csum;
+	user_read_access_end();
+	return csum;
 }
-EXPORT_SYMBOL(csum_and_copy_from_user);
 
-__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
-			     __wsum sum, int *err_ptr)
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
 {
-	unsigned int csum;
-
-	might_sleep();
-
-	*err_ptr = 0;
-
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
-
-	if (unlikely((len < 0) || !access_ok(VERIFY_WRITE, dst, len))) {
-		*err_ptr = -EFAULT;
-		csum = -1; /* invalid checksum */
-		goto out;
-	}
-
-	csum = csum_partial_copy_generic(src, (void __force *)dst,
-					 len, sum, NULL, err_ptr);
+	__wsum csum;
 
-	if (unlikely(*err_ptr)) {
-		csum = csum_partial(src, len, sum);
+	if (unlikely(!user_write_access_begin(dst, len)))
+		return 0;
 
-		if (copy_to_user(dst, src, len)) {
-			*err_ptr = -EFAULT;
-			csum = -1; /* invalid checksum */
-		}
-	}
+	csum = csum_partial_copy_generic(src, (void __force *)dst, len);
 
-out:
-	return (__force __wsum)csum;
+	user_write_access_end();
+	return csum;
 }
-EXPORT_SYMBOL(csum_and_copy_to_user);