leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

zram: fix race between zram_reset_device() and disksize_store()

Browse Source 
When the ->init_lock is released in zram_reset_device(), disksize_store()
can come in and try to allocate meta, but zram_reset_device() is freeing
free meta, so cause races.

Link: https://lore.kernel.org/linux-block/20210927163805.808907-1-mcgrof@kernel.org/T/#mc617f865a3fa2778e40f317ddf48f6447c20c073
Reported-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Link: https://lore.kernel.org/r/20211025025426.2815424-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei 2021-10-25 10:54:23 +08:00 committed by Jens Axboe
parent 494dbee341
commit 6f1637795f
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
drivers/block/zram/zram_drv.c
View File

@ -1704,12 +1704,13 @@ static void zram_reset_device(struct zram *zram)
set_capacity_and_notify(zram->disk, 0);
part_stat_set_all(zram->disk->part0, 0);
up_write(&zram->init_lock);
/* I/O operation under all of CPU are done so let's free */
zram_meta_free(zram, disksize);
memset(&zram->stats, 0, sizeof(zram->stats));
zcomp_destroy(comp);
reset_bdev(zram);
up_write(&zram->init_lock);
}
static ssize_t disksize_store(struct device *dev,