From ab596ad8972f314ace538799734c7e1bdd1da2ff Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Jan 2009 02:02:57 +0100 Subject: xfs: fix dentry aliasing issues in open_by_handle Open by handle just grabs an inode by handle and then creates itself a dentry for it. While this works for regular files it is horribly broken for directories, where the VFS locking relies on the fact that there is only just one single dentry for a given inode, and that these are always connected to the root of the filesystem so that it's locking algorithms work (see Documentations/filesystems/Locking) Remove all the existing open by handle code and replace it with a small wrapper around the exportfs code which deals with all these issues. At the same time we also make the checks for a valid handle strict enough to reject all not perfectly well formed handles - given that we never hand out others that's okay and simplifies the code. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner --- fs/xfs/linux-2.6/xfs_ioctl.h | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'fs/xfs/linux-2.6/xfs_ioctl.h') diff --git a/fs/xfs/linux-2.6/xfs_ioctl.h b/fs/xfs/linux-2.6/xfs_ioctl.h index 8c16bf2d7e03..7bd7c6afc1eb 100644 --- a/fs/xfs/linux-2.6/xfs_ioctl.h +++ b/fs/xfs/linux-2.6/xfs_ioctl.h @@ -34,16 +34,13 @@ xfs_find_handle( extern int xfs_open_by_handle( - xfs_mount_t *mp, - xfs_fsop_handlereq_t *hreq, struct file *parfilp, - struct inode *parinode); + xfs_fsop_handlereq_t *hreq); extern int xfs_readlink_by_handle( - xfs_mount_t *mp, - xfs_fsop_handlereq_t *hreq, - struct inode *parinode); + struct file *parfilp, + xfs_fsop_handlereq_t *hreq); extern int xfs_attrmulti_attr_get( @@ -67,6 +64,12 @@ xfs_attrmulti_attr_remove( char *name, __uint32_t flags); +extern struct dentry * +xfs_handle_to_dentry( + struct file *parfilp, + void __user *uhandle, + u32 hlen); + extern long xfs_file_ioctl( struct file *filp, -- cgit v1.2.3