vfs: create a generic checking function for FS_IOC_FSSETXATTR

Create a generic checking function for the incoming FS_IOC_FSSETXATTR
fsxattr values so that we can standardize some of the implementation
behaviors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>

1 files changed, 17 insertions, 8 deletions

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 272b6e44191b..1974cb755d09 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -721,6 +721,17 @@ static int ext4_ioctl_check_project(struct inode *inode, struct fsxattr *fa)
 	return 0;
 }
 
+static void ext4_fill_fsxattr(struct inode *inode, struct fsxattr *fa)
+{
+	struct ext4_inode_info *ei = EXT4_I(inode);
+
+	simple_fill_fsxattr(fa, ext4_iflags_to_xflags(ei->i_flags &
+						      EXT4_FL_USER_VISIBLE));
+
+	if (ext4_has_feature_project(inode->i_sb))
+		fa->fsx_projid = from_kprojid(&init_user_ns, ei->i_projid);
+}
+
 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct inode *inode = file_inode(filp);
@@ -1089,13 +1100,7 @@ resizefs_out:
 	{
 		struct fsxattr fa;
 
-		memset(&fa, 0, sizeof(struct fsxattr));
-		fa.fsx_xflags = ext4_iflags_to_xflags(ei->i_flags & EXT4_FL_USER_VISIBLE);
-
-		if (ext4_has_feature_project(inode->i_sb)) {
-			fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,
-				EXT4_I(inode)->i_projid);
-		}
+		ext4_fill_fsxattr(inode, &fa);
 
 		if (copy_to_user((struct fsxattr __user *)arg,
 				 &fa, sizeof(fa)))
@@ -1104,7 +1109,7 @@ resizefs_out:
 	}
 	case EXT4_IOC_FSSETXATTR:
 	{
-		struct fsxattr fa;
+		struct fsxattr fa, old_fa;
 		int err;
 
 		if (copy_from_user(&fa, (struct fsxattr __user *)arg,
@@ -1127,9 +1132,13 @@ resizefs_out:
 			return err;
 
 		inode_lock(inode);
+		ext4_fill_fsxattr(inode, &old_fa);
 		err = ext4_ioctl_check_project(inode, &fa);
 		if (err)
 			goto out;
+		err = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);
+		if (err)
+			goto out;
 		flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) |
 			 (flags & EXT4_FL_XFLAG_VISIBLE);
 		err = ext4_ioctl_setflags(inode, flags);