vfs: add a flags argument to user_path_parent

...so we can pass in LOOKUP_REVAL. For now, nothing does yet.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 6 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 6868699272bf..19190618695f 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2175,15 +2175,19 @@ int user_path_at(int dfd, const char __user *name, unsigned flags,
  *     path-walking is complete.
  */
 static struct filename *
-user_path_parent(int dfd, const char __user *path, struct nameidata *nd)
+user_path_parent(int dfd, const char __user *path, struct nameidata *nd,
+                 unsigned int flags)
 {
         struct filename *s = getname(path);
         int error;
 
+        /* only LOOKUP_REVAL is allowed in extra flags */
+        flags &= LOOKUP_REVAL;
+
         if (IS_ERR(s))
                 return s;
 
-        error = filename_lookup(dfd, s, LOOKUP_PARENT, nd);
+        error = filename_lookup(dfd, s, flags | LOOKUP_PARENT, nd);
         if (error) {
                 putname(s);
                 return ERR_PTR(error);
@@ -3336,7 +3340,7 @@ static long do_rmdir(int dfd, const char __user *pathname)
         struct dentry *dentry;
         struct nameidata nd;
 
-        name = user_path_parent(dfd, pathname, &nd);
+        name = user_path_parent(dfd, pathname, &nd, 0);
         if (IS_ERR(name))
                 return PTR_ERR(name);
 
@@ -3432,7 +3436,7 @@ static long do_unlinkat(int dfd, const char __user *pathname)
         struct nameidata nd;
         struct inode *inode = NULL;
 
-        name = user_path_parent(dfd, pathname, &nd);
+        name = user_path_parent(dfd, pathname, &nd, 0);
         if (IS_ERR(name))
                 return PTR_ERR(name);
 
@@ -3827,13 +3831,13 @@ SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
         struct filename *to;
         int error;
 
-        from = user_path_parent(olddfd, oldname, &oldnd);
+        from = user_path_parent(olddfd, oldname, &oldnd, 0);
         if (IS_ERR(from)) {
                 error = PTR_ERR(from);
                 goto exit;
         }
 
-        to = user_path_parent(newdfd, newname, &newnd);
+        to = user_path_parent(newdfd, newname, &newnd, 0);
         if (IS_ERR(to)) {
                 error = PTR_ERR(to);
                 goto exit1;