Revert "vfs: show unreachable paths in getcwd and proc"

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>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index f3d02ca461ecfcc341eb783fd15da8df486fde11..182845147fe45bde8f5607a799f23cc1e2818117 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1574,7 +1574,7 @@ static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
        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;