[XFS] Check for invalid flags in xfs_attrlist_by_handle.

xfs_attrlist_by_handle should only take the ATTR_ flags for the root
namespaces. The ATTR_KERN* flags may change at anytime and expect special
preconditions that can't be guaranteed for userspace-originating requests.
For example passing down ATTR_KERNNOVAL through xfs_attrlist_by_handle
will hit an assert in debug builds currently.

SGI-PV: 983677

SGI-Modid: xfs-linux-melb:xfs-kern:31351a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index 01939ba2d8de..993f5720200a 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -468,6 +468,12 @@ xfs_attrlist_by_handle(
         if (al_hreq.buflen > XATTR_LIST_MAX)
                 return -XFS_ERROR(EINVAL);
 
+        /*
+         * Reject flags, only allow namespaces.
+         */
+        if (al_hreq.flags & ~(ATTR_ROOT | ATTR_SECURE))
+                return -XFS_ERROR(EINVAL);
+
         error = xfs_vget_fsop_handlereq(mp, parinode, &al_hreq.hreq, &inode);
         if (error)
                 goto out;