vfs: teach vfs_ioc_fssetxattr_check to check project id info

Standardize the project id checks for FSSETXATTR.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>

fs/ext4/ioctl.c

@@ -697,30 +697,6 @@ static long ext4_ioctl_group_add(struct file *file,
 	return err;
 }
 
-static int ext4_ioctl_check_project(struct inode *inode, struct fsxattr *fa)
-{
-	/*
-	 * Project Quota ID state is only allowed to change from within the init
-	 * namespace. Enforce that restriction only if we are trying to change
-	 * the quota ID state. Everything else is allowed in user namespaces.
-	 */
-	if (current_user_ns() == &init_user_ns)
-		return 0;
-
-	if (__kprojid_val(EXT4_I(inode)->i_projid) != fa->fsx_projid)
-		return -EINVAL;
-
-	if (ext4_test_inode_flag(inode, EXT4_INODE_PROJINHERIT)) {
-		if (!(fa->fsx_xflags & FS_XFLAG_PROJINHERIT))
-			return -EINVAL;
-	} else {
-		if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
-			return -EINVAL;
-	}
-
-	return 0;
-}
-
 static void ext4_fill_fsxattr(struct inode *inode, struct fsxattr *fa)
 {
 	struct ext4_inode_info *ei = EXT4_I(inode);
@@ -1133,9 +1109,6 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 		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;

fs/inode.c

@@ -2214,6 +2214,19 @@ int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa,
 	    !capable(CAP_LINUX_IMMUTABLE))
 		return -EPERM;
 
+	/*
+	 * Project Quota ID state is only allowed to change from within the init
+	 * namespace. Enforce that restriction only if we are trying to change
+	 * the quota ID state. Everything else is allowed in user namespaces.
+	 */
+	if (current_user_ns() != &init_user_ns) {
+		if (old_fa->fsx_projid != fa->fsx_projid)
+			return -EINVAL;
+		if ((old_fa->fsx_xflags ^ fa->fsx_xflags) &
+				FS_XFLAG_PROJINHERIT)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL(vfs_ioc_fssetxattr_check);

fs/xfs/xfs_ioctl.c

@@ -1298,21 +1298,6 @@ xfs_ioctl_setattr_check_projid(
 	if (fa->fsx_projid > (uint16_t)-1 &&
 	    !xfs_sb_version_hasprojid32bit(&ip->i_mount->m_sb))
 		return -EINVAL;
-
-	/*
-	 * Project Quota ID state is only allowed to change from within the init
-	 * namespace. Enforce that restriction only if we are trying to change
-	 * the quota ID state. Everything else is allowed in user namespaces.
-	 */
-	if (current_user_ns() == &init_user_ns)
-		return 0;
-
-	if (xfs_get_projid(ip) != fa->fsx_projid)
-		return -EINVAL;
-	if ((fa->fsx_xflags & FS_XFLAG_PROJINHERIT) !=
-	    (ip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT))
-		return -EINVAL;
-
 	return 0;
 }