1 files changed, 34 insertions, 36 deletions

diff --git a/fs/udf/file.c b/fs/udf/file.c
index dbcb3a4a0cb9..356c2bf148a5 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -43,13 +43,18 @@ static void __udf_adinicb_readpage(struct page *page)
 	struct inode *inode = page->mapping->host;
 	char *kaddr;
 	struct udf_inode_info *iinfo = UDF_I(inode);
-
-	kaddr = kmap(page);
-	memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, inode->i_size);
-	memset(kaddr + inode->i_size, 0, PAGE_SIZE - inode->i_size);
+	loff_t isize = i_size_read(inode);
+
+	/*
+	 * We have to be careful here as truncate can change i_size under us.
+	 * So just sample it once and use the same value everywhere.
+	 */
+	kaddr = kmap_atomic(page);
+	memcpy(kaddr, iinfo->i_ext.i_data + iinfo->i_lenEAttr, isize);
+	memset(kaddr + isize, 0, PAGE_SIZE - isize);
 	flush_dcache_page(page);
 	SetPageUptodate(page);
-	kunmap(page);
+	kunmap_atomic(kaddr);
 }
 
 static int udf_adinicb_readpage(struct file *file, struct page *page)
@@ -70,11 +75,12 @@ static int udf_adinicb_writepage(struct page *page,
 
 	BUG_ON(!PageLocked(page));
 
-	kaddr = kmap(page);
-	memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr, inode->i_size);
-	mark_inode_dirty(inode);
+	kaddr = kmap_atomic(page);
+	memcpy(iinfo->i_ext.i_data + iinfo->i_lenEAttr, kaddr,
+		i_size_read(inode));
 	SetPageUptodate(page);
-	kunmap(page);
+	kunmap_atomic(kaddr);
+	mark_inode_dirty(inode);
 	unlock_page(page);
 
 	return 0;
@@ -176,54 +182,46 @@ long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct inode *inode = file_inode(filp);
 	long old_block, new_block;
-	int result = -EINVAL;
+	int result;
 
 	if (inode_permission(inode, MAY_READ) != 0) {
 		udf_debug("no permission to access inode %lu\n", inode->i_ino);
-		result = -EPERM;
-		goto out;
+		return -EPERM;
 	}
 
-	if (!arg) {
+	if (!arg && ((cmd == UDF_GETVOLIDENT) || (cmd == UDF_GETEASIZE) ||
+		     (cmd == UDF_RELOCATE_BLOCKS) || (cmd == UDF_GETEABLOCK))) {
 		udf_debug("invalid argument to udf_ioctl\n");
-		result = -EINVAL;
-		goto out;
+		return -EINVAL;
 	}
 
 	switch (cmd) {
 	case UDF_GETVOLIDENT:
 		if (copy_to_user((char __user *)arg,
 				 UDF_SB(inode->i_sb)->s_volume_ident, 32))
-			result = -EFAULT;
-		else
-			result = 0;
-		goto out;
+			return -EFAULT;
+		return 0;
 	case UDF_RELOCATE_BLOCKS:
-		if (!capable(CAP_SYS_ADMIN)) {
-			result = -EPERM;
-			goto out;
-		}
-		if (get_user(old_block, (long __user *)arg)) {
-			result = -EFAULT;
-			goto out;
-		}
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		if (get_user(old_block, (long __user *)arg))
+			return -EFAULT;
 		result = udf_relocate_blocks(inode->i_sb,
 						old_block, &new_block);
 		if (result == 0)
 			result = put_user(new_block, (long __user *)arg);
-		goto out;
+		return result;
 	case UDF_GETEASIZE:
-		result = put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
-		goto out;
+		return put_user(UDF_I(inode)->i_lenEAttr, (int __user *)arg);
 	case UDF_GETEABLOCK:
-		result = copy_to_user((char __user *)arg,
-				      UDF_I(inode)->i_ext.i_data,
-				      UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
-		goto out;
+		return copy_to_user((char __user *)arg,
+				    UDF_I(inode)->i_ext.i_data,
+				    UDF_I(inode)->i_lenEAttr) ? -EFAULT : 0;
+	default:
+		return -ENOIOCTLCMD;
 	}
 
-out:
-	return result;
+	return 0;
 }
 
 static int udf_release_file(struct inode *inode, struct file *filp)