[246/289] Revert "vfs: show unreachable paths in getcwd and proc"

Greg KH
2010-12-08T01:03:44Z

From: Eric W. Biederman <ebiederm@xmission.com>

commit 7b2a69ba7055da9a04eb96aa7b38c8e3280aaaa5 upstream.

Because it caused a chroot ttyname regression in 2.6.36.

As of 2.6.36 ttyname does not work in a chroot. It has already been
reported that screen breaks, and for me this breaks an automated
distribution testsuite, that I need to preserve the ability to run the
existing binaries on for several more years. glibc 2.11.3 which has a
fix for this is not an option.

The root cause of this breakage is:

commit 8df9d1a4142311c084ffeeacb67cd34d190eff74
Author: Miklos Szeredi <mszeredi@suse.cz>
Date: Tue Aug 10 11:41:41 2010 +0200

vfs: show unreachable paths in getcwd and proc

Prepend "(unreachable)" to path strings if the path is not reachable
from the current root.

Two places updated are
- the return string from getcwd()
- and symlinks under /proc/$PID.

Other uses of d_path() are left unchanged (we know that some old
software crashes if /proc/mounts is changed).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

So remove the nice sounding, but ultimately ill advised change to how
/proc/fd symlinks work.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/proc/base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1526,7 +1526,7 @@ static int do_proc_readlink(struct path
if (!tmp)
return -ENOMEM;

- pathname = d_path_with_unreachable(path, tmp, PAGE_SIZE);
+ pathname = d_path(path, tmp, PAGE_SIZE);
len = PTR_ERR(pathname);
if (IS_ERR(pathname))
goto out;