• Chris Mason's avatar
    btrfs: fix use after free iterating extrefs · dc6c5fb3
    Chris Mason authored
    The code for btrfs inode-resolve has never worked properly for
    files with enough hard links to trigger extrefs.  It was trying to
    get the leaf out of a path after freeing the path:
    
    	btrfs_release_path(path);
    	leaf = path->nodes[0];
    	item_size = btrfs_item_size_nr(leaf, slot);
    
    The fix here is to use the extent buffer we cloned just a little higher
    up to avoid deadlocks caused by using the leaf in the path.
    Signed-off-by: default avatarChris Mason <clm@fb.com>
    cc: stable@vger.kernel.org # v3.7+
    cc: Mark Fasheh <mfasheh@suse.de>
    Reviewed-by: default avatarFilipe Manana <fdmanana@suse.com>
    Reviewed-by: default avatarMark Fasheh <mfasheh@suse.de>
    dc6c5fb3
backref.c 52.1 KB