move the call of __d_drop(anon) into __d_materialise_unique(dentry, anon)

and lock the right list there

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 2 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index d30ce699ae4b..5c6e71dc23f5 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2656,6 +2656,12 @@ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon)
         dentry->d_parent = dentry;
         list_del_init(&dentry->d_u.d_child);
         anon->d_parent = dparent;
+        if (likely(!d_unhashed(anon))) {
+                hlist_bl_lock(&anon->d_sb->s_anon);
+                __hlist_bl_del(&anon->d_hash);
+                anon->d_hash.pprev = NULL;
+                hlist_bl_unlock(&anon->d_sb->s_anon);
+        }
         list_move(&anon->d_u.d_child, &dparent->d_subdirs);
 
         write_seqcount_end(&dentry->d_seq);
@@ -2714,7 +2720,6 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
                         write_seqlock(&rename_lock);
                         __d_materialise_dentry(dentry, new);
                         write_sequnlock(&rename_lock);
-                        __d_drop(new);
                         _d_rehash(new);
                         spin_unlock(&new->d_lock);
                         spin_unlock(&inode->i_lock);
@@ -2778,7 +2783,6 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode)
                                  * could splice into our tree? */
                                 __d_materialise_dentry(dentry, alias);
                                 write_sequnlock(&rename_lock);
-                                __d_drop(alias);
                                 goto found;
                         } else {
                                 /* Nope, but we must(!) avoid directory