1 files changed, 34 insertions, 6 deletions

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 2341375386f8..25435987d6ae 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -186,16 +186,26 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,
 {
         struct dentry *root = sbi->sb->s_root;
         struct dentry *tmp;
-        char *buf = *name;
+        char *buf;
         char *p;
-        int len = 0;
+        int len;
+        unsigned seq;
 
-        spin_lock(&dcache_lock);
+rename_retry:
+        buf = *name;
+        len = 0;
+
+        seq = read_seqbegin(&rename_lock);
+        rcu_read_lock();
+        spin_lock(&sbi->fs_lock);
         for (tmp = dentry ; tmp != root ; tmp = tmp->d_parent)
                 len += tmp->d_name.len + 1;
 
         if (!len || --len > NAME_MAX) {
-                spin_unlock(&dcache_lock);
+                spin_unlock(&sbi->fs_lock);
+                rcu_read_unlock();
+                if (read_seqretry(&rename_lock, seq))
+                        goto rename_retry;
                 return 0;
         }
 
@@ -208,7 +218,10 @@ static int autofs4_getpath(struct autofs_sb_info *sbi,
                 p -= tmp->d_name.len;
                 strncpy(p, tmp->d_name.name, tmp->d_name.len);
         }
-        spin_unlock(&dcache_lock);
+        spin_unlock(&sbi->fs_lock);
+        rcu_read_unlock();
+        if (read_seqretry(&rename_lock, seq))
+                goto rename_retry;
 
         return len;
 }
@@ -296,6 +309,9 @@ static int validate_request(struct autofs_wait_queue **wait,
          * completed while we waited on the mutex ...
          */
         if (notify == NFY_MOUNT) {
+                struct dentry *new = NULL;
+                int valid = 1;
+
                 /*
                  * If the dentry was successfully mounted while we slept
                  * on the wait queue mutex we can return success. If it
@@ -303,8 +319,20 @@ static int validate_request(struct autofs_wait_queue **wait,
                  * a multi-mount with no mount at it's base) we can
                  * continue on and create a new request.
                  */
+                if (!IS_ROOT(dentry)) {
+                        if (dentry->d_inode && d_unhashed(dentry)) {
+                                struct dentry *parent = dentry->d_parent;
+                                new = d_lookup(parent, &dentry->d_name);
+                                if (new)
+                                        dentry = new;
+                        }
+                }
                 if (have_submounts(dentry))
-                        return 0;
+                        valid = 0;
+
+                if (new)
+                        dput(new);
+                return valid;
         }
 
         return 1;