ext4: Fix ext4_dx_readdir hash collision handling

This fixes a bug where readdir() would return a directory entry twice
if there was a hash collision in an hash tree indexed directory.

Signed-off-by: Eugene Dashevsky <eugene@ibrix.com>
Signed-off-by: Mike Snitzer <msnitzer@ibrix.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 15 insertions, 5 deletions

diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index d3d23d73c08b..ec8e33b45219 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -411,7 +411,7 @@ static int call_filldir(struct file * filp, void * dirent,
                                 get_dtype(sb, fname->file_type));
                 if (error) {
                         filp->f_pos = curr_pos;
-                        info->extra_fname = fname->next;
+                        info->extra_fname = fname;
                         return error;
                 }
                 fname = fname->next;
@@ -450,11 +450,21 @@ static int ext4_dx_readdir(struct file * filp,
          * If there are any leftover names on the hash collision
          * chain, return them first.
          */
-        if (info->extra_fname &&
-            call_filldir(filp, dirent, filldir, info->extra_fname))
-                goto finished;
+        if (info->extra_fname) {
+                if (call_filldir(filp, dirent, filldir, info->extra_fname))
+                        goto finished;
 
-        if (!info->curr_node)
+                info->extra_fname = NULL;
+                info->curr_node = rb_next(info->curr_node);
+                if (!info->curr_node) {
+                        if (info->next_hash == ~0) {
+                                filp->f_pos = EXT4_HTREE_EOF;
+                                goto finished;
+                        }
+                        info->curr_hash = info->next_hash;
+                        info->curr_minor_hash = 0;
+                }
+        } else if (!info->curr_node)
                 info->curr_node = rb_first(&info->root);
 
         while (1) {