iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ubi: fastmap: Cancel work upon detach

Browse Source 
commit 6e7d80161066c99d12580d1b985cb1408bb58cf1 upstream.

Ben Hutchings pointed out that 29b7a6fa1ec0 ("ubi: fastmap: Don't flush
fastmap work on detach") does not really fix the problem, it just
reduces the risk to hit the race window where fastmap work races against
free()'ing ubi->volumes[].

The correct approach is making sure that no more fastmap work is in
progress before we free ubi data structures.
So we cancel fastmap work right after the ubi background thread is
stopped.
By setting ubi->thread_enabled to zero we make sure that no further work
tries to wake the thread.

Fixes: 29b7a6fa1ec0 ("ubi: fastmap: Don't flush fastmap work on detach")
Fixes: 74cdaf24004a ("UBI: Fastmap: Fix memory leaks while closing the WL sub-system")
Cc: stable@vger.kernel.org
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Cc: Martin Townsend <mtownsend1973@gmail.com>

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Richard Weinberger 2018-05-16 22:17:03 +02:00 committed by Greg Kroah-Hartman
parent db04f92b65
commit b24d90f4d6
2 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/mtd/ubi/build.c
View File

@ -1082,6 +1082,9 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
if (ubi->bgt_thread)
kthread_stop(ubi->bgt_thread);
#ifdef CONFIG_MTD_UBI_FASTMAP
cancel_work_sync(&ubi->fm_work);
#endif
ubi_debugfs_exit_dev(ubi);
uif_close(ubi);

4
drivers/mtd/ubi/wl.c
View File

@ -1505,6 +1505,7 @@ int ubi_thread(void *u)
}
dbg_wl("background thread \"%s\" is killed", ubi->bgt_name);
ubi->thread_enabled = 0;
return 0;
}
@ -1514,9 +1515,6 @@ int ubi_thread(void *u)
*/
static void shutdown_work(struct ubi_device *ubi)
{
#ifdef CONFIG_MTD_UBI_FASTMAP
flush_work(&ubi->fm_work);
#endif
while (!list_empty(&ubi->works)) {
struct ubi_work *wrk;