From: Miao Xie <miaox@cn.fujitsu.com>
Date: Tue, 2 Feb 2010 08:46:44 +0000 (+0000)
Subject: Btrfs: remove BUG_ON() due to mounting bad filesystem
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d7ce5843bb28ada6845ab2ae8510ba3f12d33154;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git

Btrfs: remove BUG_ON() due to mounting bad filesystem

Mounting a bad filesystem caused a BUG_ON(). The following is steps to
reproduce it.
 # mkfs.btrfs /dev/sda2
 # mount /dev/sda2 /mnt
 # mkfs.btrfs /dev/sda1 /dev/sda2
 (the program says that /dev/sda2 was mounted, and then exits. )
 # umount /mnt
 # mount /dev/sda1 /mnt

At the third step, mkfs.btrfs exited in the way of make filesystem. So the
initialization of the filesystem didn't finish. So the filesystem was bad, and
it caused BUG_ON() when mounting it. But BUG_ON() should be called by the wrong
code, not user's operation, so I think it is a bug of btrfs.

This patch fixes it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 87b25543d7d..2b59201b955 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1982,7 +1982,12 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
 	if (!(sb->s_flags & MS_RDONLY)) {
 		ret = btrfs_recover_relocation(tree_root);
-		BUG_ON(ret);
+		if (ret < 0) {
+			printk(KERN_WARNING
+			       "btrfs: failed to recover relocation\n");
+			err = -EINVAL;
+			goto fail_trans_kthread;
+		}
 	}
 
 	location.objectid = BTRFS_FS_TREE_OBJECTID;
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index ed3e4a2ec2c..ab7ab531874 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -3764,7 +3764,8 @@ out:
 				       BTRFS_DATA_RELOC_TREE_OBJECTID);
 		if (IS_ERR(fs_root))
 			err = PTR_ERR(fs_root);
-		btrfs_orphan_cleanup(fs_root);
+		else
+			btrfs_orphan_cleanup(fs_root);
 	}
 	return err;
 }