ext4: add missing ext4_resize_end on error paths

Online resize ioctls 'EXT4_IOC_GROUP_EXTEND' and 'EXT4_IOC_GROUP_ADD'
call ext4_resize_begin() to check permissions and to set the
EXT4_RESIZING bit lock, they do their work and they must finish with
ext4_resize_end() which calls clear_bit_unlock() to unlock and to
avoid -EBUSY errors for the next resize operations.

This patch adds the missing ext4_resize_end() calls on error paths.

Patch tested.

Cc: stable@vger.kernel.org
Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index c1a9880..b81a5f1 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -184,19 +184,22 @@
 		if (err)
 			return err;
 
-		if (get_user(n_blocks_count, (__u32 __user *)arg))
-			return -EFAULT;
+		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
+			err = -EFAULT;
+			goto group_extend_out;
+		}
 
 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 			ext4_msg(sb, KERN_ERR,
 				 "Online resizing not supported with bigalloc");
-			return -EOPNOTSUPP;
+			err = -EOPNOTSUPP;
+			goto group_extend_out;
 		}
 
 		err = mnt_want_write(filp->f_path.mnt);
 		if (err)
-			return err;
+			goto group_extend_out;
 
 		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
 		if (EXT4_SB(sb)->s_journal) {
@@ -206,9 +209,10 @@
 		}
 		if (err == 0)
 			err = err2;
-		mnt_drop_write(filp->f_path.mnt);
-		ext4_resize_end(sb);
 
+		mnt_drop_write(filp->f_path.mnt);
+group_extend_out:
+		ext4_resize_end(sb);
 		return err;
 	}
 
@@ -267,19 +271,22 @@
 			return err;
 
 		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
-				sizeof(input)))
-			return -EFAULT;
+				sizeof(input))) {
+			err = -EFAULT;
+			goto group_add_out;
+		}
 
 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
 			ext4_msg(sb, KERN_ERR,
 				 "Online resizing not supported with bigalloc");
-			return -EOPNOTSUPP;
+			err = -EOPNOTSUPP;
+			goto group_add_out;
 		}
 
 		err = mnt_want_write(filp->f_path.mnt);
 		if (err)
-			return err;
+			goto group_add_out;
 
 		err = ext4_group_add(sb, &input);
 		if (EXT4_SB(sb)->s_journal) {
@@ -289,9 +296,10 @@
 		}
 		if (err == 0)
 			err = err2;
-		mnt_drop_write(filp->f_path.mnt);
-		ext4_resize_end(sb);
 
+		mnt_drop_write(filp->f_path.mnt);
+group_add_out:
+		ext4_resize_end(sb);
 		return err;
 	}