3 files changed, 20 insertions, 12 deletions

diff --git a/fs/namei.c b/fs/namei.c
index a9b94c62c303..0e1b9c3eb36d 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -586,6 +586,21 @@ static inline void path_to_nameidata(const struct path *path,
         nd->path.dentry = path->dentry;
 }
 
+/*
+ * Helper to directly jump to a known parsed path from ->follow_link,
+ * caller must have taken a reference to path beforehand.
+ */
+void nd_jump_link(struct nameidata *nd, struct path *path)
+{
+        path_put(&nd->path);
+
+        nd->path = *path;
+        nd->inode = nd->path.dentry->d_inode;
+        nd->flags |= LOOKUP_JUMPED;
+
+        BUG_ON(nd->inode->i_op->follow_link);
+}
+
 static inline void put_link(struct nameidata *nd, struct path *link, void *cookie)
 {
         struct inode *inode = link->dentry->d_inode;
@@ -630,17 +645,9 @@ follow_link(struct path *link, struct nameidata *nd, void **p)
         s = nd_get_link(nd);
         if (s) {
                 error = __vfs_follow_link(nd, s);
-        } else if (nd->last_type == LAST_BIND) {
-                nd->flags |= LOOKUP_JUMPED;
-                nd->inode = nd->path.dentry->d_inode;
-                if (nd->inode->i_op->follow_link) {
-                        /* stepped on a _really_ weird one */
-                        path_put(&nd->path);
-                        error = -ELOOP;
-                }
+                if (unlikely(error))
+                        put_link(nd, link, *p);
         }
-        if (unlikely(error))
-                put_link(nd, link, *p);
 
         return error;
 
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 3bd5ac1ff018..2772208338f8 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1438,8 +1438,7 @@ static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
         if (error)
                 goto out;
 
-        path_put(&nd->path);
-        nd->path = path;
+        nd_jump_link(nd, &path);
         return NULL;
 out:
         return ERR_PTR(error);
diff --git a/include/linux/namei.h b/include/linux/namei.h
index f5931489e150..d2ef8b34b967 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -80,6 +80,8 @@ extern int follow_up(struct path *);
 extern struct dentry *lock_rename(struct dentry *, struct dentry *);
 extern void unlock_rename(struct dentry *, struct dentry *);
 
+extern void nd_jump_link(struct nameidata *nd, struct path *path);
+
 static inline void nd_set_link(struct nameidata *nd, char *path)
 {
         nd->saved_names[nd->depth] = path;