[ Upstream commit c16f39d14a ]
When CONFIG_MTD_UBI_FASTMAP is enabled, fm_anchor will be assigned
a free PEB during ubi_wl_init() or ubi_update_fastmap(). However
if fastmap is not used or disabled on the MTD device, ubi_wl_entry
related with the PEB will not be freed during detach.
So Fix it by freeing the unused fastmap anchor during detach.
Fixes: f9c34bb529 ("ubi: Fix producing anchor PEBs")
Reported-by: syzbot+f317896aae32eb281a58@syzkaller.appspotmail.com
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ca1704f177