From 711b2b76b706c9833d2b8ab52a48ec481d70248c Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@redhat.com>
Date: Wed, 10 Oct 2012 15:25:29 -0400
Subject: [PATCH] --- yaml --- r: 333907 b: refs/heads/master c:
 873f1eedc1b983d772283279192c4ca2f60e8482 h: refs/heads/master i:   333905:
 b8f0c989207247be8440fd6adb1e2a6690d07bf4   333903:
 cdf42c12dfc0c35aededc75215e144e068b27798 v: v3

---
 [refs]           |  2 +-
 trunk/fs/namei.c | 30 +++++++++++++++++++++++-------
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/[refs] b/[refs]
index 6948d2e8461d..511f2d214fe4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7ac86265dc8f665cc49d6e60a125e608cd2fca14
+refs/heads/master: 873f1eedc1b983d772283279192c4ca2f60e8482
diff --git a/trunk/fs/namei.c b/trunk/fs/namei.c
index 5dbc3f836934..8c14353fb750 100644
--- a/trunk/fs/namei.c
+++ b/trunk/fs/namei.c
@@ -1988,20 +1988,30 @@ static int path_lookupat(int dfd, const char *name,
 	return err;
 }
 
-static int do_path_lookup(int dfd, const char *name,
+static int filename_lookup(int dfd, struct filename *name,
 				unsigned int flags, struct nameidata *nd)
 {
-	int retval = path_lookupat(dfd, name, flags | LOOKUP_RCU, nd);
+	int retval = path_lookupat(dfd, name->name, flags | LOOKUP_RCU, nd);
 	if (unlikely(retval == -ECHILD))
-		retval = path_lookupat(dfd, name, flags, nd);
+		retval = path_lookupat(dfd, name->name, flags, nd);
 	if (unlikely(retval == -ESTALE))
-		retval = path_lookupat(dfd, name, flags | LOOKUP_REVAL, nd);
+		retval = path_lookupat(dfd, name->name,
+						flags | LOOKUP_REVAL, nd);
 
 	if (likely(!retval))
-		audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT);
+		audit_inode(name->name, nd->path.dentry,
+						flags & LOOKUP_PARENT);
 	return retval;
 }
 
+static int do_path_lookup(int dfd, const char *name,
+				unsigned int flags, struct nameidata *nd)
+{
+	struct filename filename = { .name = name };
+
+	return filename_lookup(dfd, &filename, flags, nd);
+}
+
 /* does lookup, returns the object with parent locked */
 struct dentry *kern_path_locked(const char *name, struct path *path)
 {
@@ -2125,7 +2135,7 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
 
 		BUG_ON(flags & LOOKUP_PARENT);
 
-		err = do_path_lookup(dfd, tmp->name, flags, &nd);
+		err = filename_lookup(dfd, tmp, flags, &nd);
 		putname(tmp);
 		if (!err)
 			*path = nd.path;
@@ -2139,6 +2149,12 @@ int user_path_at(int dfd, const char __user *name, unsigned flags,
 	return user_path_at_empty(dfd, name, flags, path, NULL);
 }
 
+/*
+ * NB: most callers don't do anything directly with the reference to the
+ *     to struct filename, but the nd->last pointer points into the name string
+ *     allocated by getname. So we must hold the reference to it until all
+ *     path-walking is complete.
+ */
 static struct filename *
 user_path_parent(int dfd, const char __user *path, struct nameidata *nd)
 {
@@ -2148,7 +2164,7 @@ user_path_parent(int dfd, const char __user *path, struct nameidata *nd)
 	if (IS_ERR(s))
 		return s;
 
-	error = do_path_lookup(dfd, s->name, LOOKUP_PARENT, nd);
+	error = filename_lookup(dfd, s, LOOKUP_PARENT, nd);
 	if (error) {
 		putname(s);
 		return ERR_PTR(error);