1 files changed, 40 insertions, 0 deletions

diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 60c2b944d762..79cf7f616bbe 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -544,6 +544,34 @@ static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
 }
 
 /*
+ * Check if root directory is empty (has less than 3 files).
+ *
+ * Used to detect broken CDs where ISO root directory is empty but Joliet root
+ * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
+ * (and Joliet used instead) or else no files would be visible.
+ */
+static bool rootdir_empty(struct super_block *sb, unsigned long block)
+{
+        int offset = 0, files = 0, de_len;
+        struct iso_directory_record *de;
+        struct buffer_head *bh;
+
+        bh = sb_bread(sb, block);
+        if (!bh)
+                return true;
+        while (files < 3) {
+                de = (struct iso_directory_record *) (bh->b_data + offset);
+                de_len = *(unsigned char *) de;
+                if (de_len == 0)
+                        break;
+                files++;
+                offset += de_len;
+        }
+        brelse(bh);
+        return files < 3;
+}
+
+/*
  * Initialize the superblock and read the root inode.
  *
  * Note: a check_disk_change() has been done immediately prior
@@ -843,6 +871,18 @@ root_found:
                 goto out_no_root;
 
         /*
+         * Fix for broken CDs with Rock Ridge and empty ISO root directory but
+         * correct Joliet root directory.
+         */
+        if (sbi->s_rock == 1 && joliet_level &&
+                                rootdir_empty(s, sbi->s_firstdatazone)) {
+                printk(KERN_NOTICE
+                        "ISOFS: primary root directory is empty. "
+                        "Disabling Rock Ridge and switching to Joliet.");
+                sbi->s_rock = 0;
+        }
+
+        /*
          * If this disk has both Rock Ridge and Joliet on it, then we
          * want to use Rock Ridge by default.  This can be overridden
          * by using the norock mount option.  There is still one other