Merge tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong:
 "Here's a patch series that sets up common parameter checking functions
  for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations.

  The goal here is to reduce the amount of behaviorial variance between
  the filesystems where those ioctls originated (ext2 and XFS,
  respectively) and everybody else.

   - Standardize parameter checking for the SETFLAGS and FSSETXATTR
     ioctls (which were the file attribute setters for ext4 and xfs and
     have now been hoisted to the vfs)

   - Only allow the DAX flag to be set on files and directories"

* tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  vfs: only allow FSSETXATTR to set DAX flag on files and dirs
  vfs: teach vfs_ioc_fssetxattr_check to check extent size hints
  vfs: teach vfs_ioc_fssetxattr_check to check project id info
  vfs: create a generic checking function for FS_IOC_FSSETXATTR
  vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

1 files changed, 4 insertions, 12 deletions

diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 0367c0039e68..1b853fb0b163 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c
@@ -60,18 +60,10 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		}
 		oldflags = ei->i_flags;
 
-		/*
-		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
-		 * the relevant capability.
-		 *
-		 * This test looks nicer. Thanks to Pauline Middelink
-		 */
-		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
-			if (!capable(CAP_LINUX_IMMUTABLE)) {
-				inode_unlock(inode);
-				ret = -EPERM;
-				goto setflags_out;
-			}
+		ret = vfs_ioc_setflags_prepare(inode, oldflags, flags);
+		if (ret) {
+			inode_unlock(inode);
+			goto setflags_out;
 		}
 
 		flags = flags & EXT2_FL_USER_MODIFIABLE;