opening symlinks with O_CREAT under latest 2.5.74

[Trond Myklebust <trond.myklebust@fys.uio.no>]

>>>>> " " == Petr Vandrovec <vandrove@vc.cvut.cz> writes:

     > Hi,
     >   couple of things stopped working on my box
     > where I have /dev/vc/XX as symlinks to /dev/ttyXX, and some
     > things use /dev/vc/XX and some /dev/ttyXX. After last update
     > hour ago things which use /dev/vc/XX stopped working for
     > non-root - they now fail with EACCES error if they attempt to
     > redirect its input or output through '>' or '<>' bash
     > redirection operators:

Whoops. Looks like I missed an assumption in open_namei().
Does the following patch fix the problem?

Cheers,
  Trond

--- linux-2.5.74-up/fs/namei.c.orig	2003-06-30 08:49:25.000000000 +0200
+++ linux-2.5.74-up/fs/namei.c	2003-07-07 21:25:00.000000000 +0200
@@ -1344,6 +1344,7 @@
 	 * stored in nd->last.name and we will have to putname() it when we
 	 * are done. Procfs-like symlinks just set LAST_BIND.
 	 */
+	nd->flags |= LOOKUP_PARENT;
 	error = security_inode_follow_link(dentry, nd);
 	if (error)
 		goto exit_dput;
@@ -1352,6 +1353,7 @@
 	dput(dentry);
 	if (error)
 		return error;
+	nd->flags &= ~LOOKUP_PARENT;
 	if (nd->last_type == LAST_BIND) {
 		dentry = nd->dentry;
 		goto ok;