4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Nikolay Borisov nborisov@suse.com
commit f3038ee3a3f1017a1cbe9907e31fa12d366c5dcb upstream.
This function was introduced by 247e743cbe6e ("Btrfs: Use async helpers to deal with pages that have been improperly dirtied") and it didn't do any error handling then. This function might very well fail in ENOMEM situation, yet it's not handled, this could lead to inconsistent state. So let's handle the failure by setting the mapping error bit.
Signed-off-by: Nikolay Borisov nborisov@suse.com Reviewed-by: Qu Wenruo wqu@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/inode.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2015,7 +2015,15 @@ again: goto out; }
- btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state); + ret = btrfs_set_extent_delalloc(inode, page_start, page_end, + &cached_state); + if (ret) { + mapping_set_error(page->mapping, ret); + end_extent_writepage(page, ret, page_start, page_end); + ClearPageChecked(page); + goto out; + } + ClearPageChecked(page); set_page_dirty(page); out: