The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 315bf8ef914f31d51d084af950703aa1e09a728c Mon Sep 17 00:00:00 2001
From: Josef Bacik <josef@xxxxxxxxxxxxxx>
Date: Thu, 13 Feb 2020 10:47:28 -0500
Subject: [PATCH] btrfs: reset fs_root to NULL on error in open_ctree
While running my error injection script I hit a panic when we tried to
clean up the fs_root when freeing the fs_root. This is because
fs_info->fs_root == PTR_ERR(-EIO), which isn't great. Fix this by
setting fs_info->fs_root = NULL; if we fail to read the root.
CC: stable@xxxxxxxxxxxxxxx # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index d7fec89974cb..197352f23534 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3200,6 +3200,7 @@ int __cold open_ctree(struct super_block *sb,
if (IS_ERR(fs_info->fs_root)) {
err = PTR_ERR(fs_info->fs_root);
btrfs_warn(fs_info, "failed to read fs tree: %d", err);
+ fs_info->fs_root = NULL;
goto fail_qgroup;
}
