vfs: fix return value from do_last()

commit 7f6c7e62fcc123e6bd9206da99a2163fe3facc31 upstream.

complete_walk() returns either ECHILD or ESTALE.  do_last() turns this into
ECHILD unconditionally.  If not in RCU mode, this error will reach userspace
which is complete nonsense.

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

diff --git a/fs/namei.c b/fs/namei.c
index f7593c0899d19ca0e316a372190da9134138775c..91188604ffec0728049bf602eb7e63ec5b3f36ee 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2109,7 +2109,7 @@ static struct file *do_last(struct nameidata *nd, struct path *path,
                /* sayonara */
                error = complete_walk(nd);
                if (error)
-                       return ERR_PTR(-ECHILD);
+                       return ERR_PTR(error);
 
                error = -ENOTDIR;
                if (nd->flags & LOOKUP_DIRECTORY) {