Currently following a symlink never uses rcu-walk, so
terminate_walk isn't needed.
That will change in a future patch.  In preparation, change
some
  path_put_condtional()
  path_put()
sequences to
  path_to_nameidata()
  terminate_walk()

These sequence are identical when in ref-walk, and correct when in
rcu-walk.

Also change two path_put() calls to equivalent terminate_walk().

Signed-off-by: NeilBrown <ne...@suse.de>
---
 fs/namei.c |   40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 9a5d429f2a8a..8cb89a0d30ba 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -749,6 +749,18 @@ char *nd_get_link(void)
 }
 EXPORT_SYMBOL(nd_get_link);
 
+static void terminate_walk(struct nameidata *nd)
+{
+       if (!(nd->flags & LOOKUP_RCU)) {
+               path_put(&nd->path);
+       } else {
+               nd->flags &= ~LOOKUP_RCU;
+               if (!(nd->flags & LOOKUP_ROOT))
+                       nd->root.mnt = NULL;
+               rcu_read_unlock();
+       }
+}
+
 static inline void put_link(struct nameidata *nd, struct path *link, void 
*cookie)
 {
        struct inode *inode = link->dentry->d_inode;
@@ -799,8 +811,8 @@ static inline int may_follow_link(struct path *link, struct 
nameidata *nd)
                return 0;
 
        audit_log_link_denied("follow_link", link);
-       path_put_conditional(link, nd);
-       path_put(&nd->path);
+       path_to_nameidata(link, nd);
+       terminate_walk(nd);
        return -EACCES;
 }
 
@@ -909,7 +921,7 @@ follow_link(struct path *link, struct nameidata *nd, void 
**p)
        s = nd_get_link();
        if (s) {
                if (unlikely(IS_ERR(s))) {
-                       path_put(&nd->path);
+                       terminate_walk(nd);
                        put_link(nd, link, *p);
                        return PTR_ERR(s);
                }
@@ -931,7 +943,7 @@ follow_link(struct path *link, struct nameidata *nd, void 
**p)
 
 out_put_nd_path:
        *p = NULL;
-       path_put(&nd->path);
+       terminate_walk(nd);
        path_put(link);
        return error;
 }
@@ -1562,18 +1574,6 @@ static inline int handle_dots(struct nameidata *nd, int 
type)
        return 0;
 }
 
-static void terminate_walk(struct nameidata *nd)
-{
-       if (!(nd->flags & LOOKUP_RCU)) {
-               path_put(&nd->path);
-       } else {
-               nd->flags &= ~LOOKUP_RCU;
-               if (!(nd->flags & LOOKUP_ROOT))
-                       nd->root.mnt = NULL;
-               rcu_read_unlock();
-       }
-}
-
 /*
  * Do we need to follow links? We _really_ want to be able
  * to do this check without having to look at inode->i_op,
@@ -1645,8 +1645,8 @@ static inline int nested_symlink(struct path *path, 
struct nameidata *nd)
        int res;
 
        if (unlikely(current->nameidata->link_count >= MAX_NESTED_LINKS)) {
-               path_put_conditional(path, nd);
-               path_put(&nd->path);
+               path_to_nameidata(path, nd);
+               terminate_walk(nd);
                return -ELOOP;
        }
        BUG_ON(nd->depth >= MAX_NESTED_LINKS);
@@ -3267,8 +3267,8 @@ static struct file *path_openat(int dfd, struct filename 
*pathname,
                struct path link = path;
                void *cookie;
                if (!(nd->flags & LOOKUP_FOLLOW)) {
-                       path_put_conditional(&path, nd);
-                       path_put(&nd->path);
+                       path_to_nameidata(&path, nd);
+                       terminate_walk(nd);
                        error = -ELOOP;
                        break;
                }


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