xfs: don't allow reflinked dir/dev/fifo/socket/pipe files

Only non-rt files can be reflinked, so check that when we load an
inode.  Also, don't leak the attr fork if there's a failure.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

1 files changed, 22 insertions, 1 deletions

diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
index bbcc8c7a44b3..7699a033dd3c 100644
--- a/fs/xfs/libxfs/xfs_inode_fork.c
+++ b/fs/xfs/libxfs/xfs_inode_fork.c
@@ -121,6 +121,26 @@ xfs_iformat_fork(
                 return -EFSCORRUPTED;
         }
 
+        if (unlikely(xfs_is_reflink_inode(ip) &&
+            (VFS_I(ip)->i_mode & S_IFMT) != S_IFREG)) {
+                xfs_warn(ip->i_mount,
+                        "corrupt dinode %llu, wrong file type for reflink.",
+                        ip->i_ino);
+                XFS_CORRUPTION_ERROR("xfs_iformat(reflink)",
+                                     XFS_ERRLEVEL_LOW, ip->i_mount, dip);
+                return -EFSCORRUPTED;
+        }
+
+        if (unlikely(xfs_is_reflink_inode(ip) &&
+            (ip->i_d.di_flags & XFS_DIFLAG_REALTIME))) {
+                xfs_warn(ip->i_mount,
+                        "corrupt dinode %llu, has reflink+realtime flag set.",
+                        ip->i_ino);
+                XFS_CORRUPTION_ERROR("xfs_iformat(reflink)",
+                                     XFS_ERRLEVEL_LOW, ip->i_mount, dip);
+                return -EFSCORRUPTED;
+        }
+
         switch (VFS_I(ip)->i_mode & S_IFMT) {
         case S_IFIFO:
         case S_IFCHR:
@@ -208,7 +228,8 @@ xfs_iformat_fork(
                         XFS_CORRUPTION_ERROR("xfs_iformat(8)",
                                              XFS_ERRLEVEL_LOW,
                                              ip->i_mount, dip);
-                        return -EFSCORRUPTED;
+                        error = -EFSCORRUPTED;
+                        break;
                 }
 
                 error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);