[PATCH] Fix do_path_lookup() to add the check for error in link_path_walk()

Fix do_path_lookup() to avoid accessing invalid dentry or inode when the
link_path_walk() has failed.  This should fix Bugme #5897.

Signed-off-by: Suzuki K P <suzuki@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/namei.c b/fs/namei.c
index faf61c35308c..e28de846c591 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1119,9 +1119,11 @@ static int fastcall do_path_lookup(int dfd, const char *name,
         current->total_link_count = 0;
         retval = link_path_walk(name, nd);
 out:
-        if (unlikely(current->audit_context
-                     && nd && nd->dentry && nd->dentry->d_inode))
+        if (likely(retval == 0)) {
+                if (unlikely(current->audit_context && nd && nd->dentry &&
+                                nd->dentry->d_inode))
                 audit_inode(name, nd->dentry->d_inode, flags);
+        }
         return retval;
 
 fput_unlock_fail: