| From: Liu Bo <bo.li.liu@oracle.com> |
| Date: Fri, 2 Sep 2016 12:35:34 -0700 |
| Subject: Btrfs: fix BUG_ON in btrfs_mark_buffer_dirty |
| |
| commit ef85b25e982b5bba1530b936e283ef129f02ab9d upstream. |
| |
| This can only happen with CONFIG_BTRFS_FS_CHECK_INTEGRITY=y. |
| |
| Commit 1ba98d0 ("Btrfs: detect corruption when non-root leaf has zero item") |
| assumes that a leaf is its root when leaf->bytenr == btrfs_root_bytenr(root), |
| however, we should not use btrfs_root_bytenr(root) since it's mainly got |
| updated during committing transaction. So the check can fail when doing |
| COW on this leaf while it is a root. |
| |
| This changes to use "if (leaf == btrfs_root_node(root))" instead, just like |
| how we check whether leaf is a root in __btrfs_cow_block(). |
| |
| Fixes: 1ba98d086fe3 (Btrfs: detect corruption when non-root leaf has zero item) |
| Reported-by: Jeff Mahoney <jeffm@suse.com> |
| Signed-off-by: Liu Bo <bo.li.liu@oracle.com> |
| Reviewed-by: Filipe Manana <fdmanana@suse.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| fs/btrfs/disk-io.c | 10 +++++++--- |
| 1 file changed, 7 insertions(+), 3 deletions(-) |
| |
| --- a/fs/btrfs/disk-io.c |
| +++ b/fs/btrfs/disk-io.c |
| @@ -533,13 +533,17 @@ static noinline int check_leaf(struct bt |
| * open_ctree() some roots has not yet been set up. |
| */ |
| if (!IS_ERR_OR_NULL(check_root)) { |
| + struct extent_buffer *eb; |
| + |
| + eb = btrfs_root_node(check_root); |
| /* if leaf is the root, then it's fine */ |
| - if (leaf->start != |
| - btrfs_root_bytenr(&check_root->root_item)) { |
| + if (leaf != eb) { |
| CORRUPT("non-root leaf's nritems is 0", |
| - leaf, root, 0); |
| + leaf, check_root, 0); |
| + free_extent_buffer(eb); |
| return -EIO; |
| } |
| + free_extent_buffer(eb); |
| } |
| return 0; |
| } |
