From: Hou Tao houtao1@huawei.com
commit c16f39d14a7e0ec59881fbdb22ae494907534384 upstream.
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: f9c34bb52997 ("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: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/mtd/ubi/fastmap-wl.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
--- a/drivers/mtd/ubi/fastmap-wl.c +++ b/drivers/mtd/ubi/fastmap-wl.c @@ -39,6 +39,13 @@ static struct ubi_wl_entry *find_anchor_ return victim; }
+static inline void return_unused_peb(struct ubi_device *ubi, + struct ubi_wl_entry *e) +{ + wl_tree_add(e, &ubi->free); + ubi->free_count++; +} + /** * return_unused_pool_pebs - returns unused PEB to the free tree. * @ubi: UBI device description object @@ -52,8 +59,7 @@ static void return_unused_pool_pebs(stru
for (i = pool->used; i < pool->size; i++) { e = ubi->lookuptbl[pool->pebs[i]]; - wl_tree_add(e, &ubi->free); - ubi->free_count++; + return_unused_peb(ubi, e); } }
@@ -361,6 +367,11 @@ static void ubi_fastmap_close(struct ubi return_unused_pool_pebs(ubi, &ubi->fm_pool); return_unused_pool_pebs(ubi, &ubi->fm_wl_pool);
+ if (ubi->fm_anchor) { + return_unused_peb(ubi, ubi->fm_anchor); + ubi->fm_anchor = NULL; + } + if (ubi->fm) { for (i = 0; i < ubi->fm->used_blocks; i++) kfree(ubi->fm->e[i]);