From: Ming Lei <ming.lei@redhat.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org, Luis Chamberlain <mcgrof@kernel.org>,
Minchan Kim <minchan@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, Ming Lei <ming.lei@redhat.com>
Subject: [PATCH V2 1/4] zram: fix race between zram_reset_device() and disksize_store()
Date: Wed, 20 Oct 2021 09:55:45 +0800 [thread overview]
Message-ID: <20211020015548.2374568-2-ming.lei@redhat.com> (raw)
In-Reply-To: <20211020015548.2374568-1-ming.lei@redhat.com>
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>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
drivers/block/zram/zram_drv.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index a68297fb51a2..25d781dc5fef 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -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,
--
2.31.1
next prev parent reply other threads:[~2021-10-20 1:56 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-20 1:55 [PATCH V2 0/4] zram: fix two races and one zram leak Ming Lei
2021-10-20 1:55 ` Ming Lei [this message]
2021-10-21 23:03 ` [PATCH V2 1/4] zram: fix race between zram_reset_device() and disksize_store() Luis Chamberlain
2021-10-20 1:55 ` [PATCH V2 2/4] zram: don't fail to remove zram during unloading module Ming Lei
2021-10-21 23:50 ` Luis Chamberlain
2021-10-22 0:38 ` Ming Lei
2021-10-20 1:55 ` [PATCH V2 3/4] zram: avoid race between zram_remove and disksize_store Ming Lei
2021-10-22 19:02 ` Luis Chamberlain
2021-10-20 1:55 ` [PATCH V2 4/4] zram: replace fsync_bdev with sync_blockdev Ming Lei
2021-10-22 19:06 ` Luis Chamberlain
2021-10-20 21:40 ` [PATCH V2 0/4] zram: fix two races and one zram leak Minchan Kim
2021-10-21 17:39 ` Luis Chamberlain
2021-10-21 17:46 ` Luis Chamberlain
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20211020015548.2374568-2-ming.lei@redhat.com \
--to=ming.lei@redhat.com \
--cc=axboe@kernel.dk \
--cc=gregkh@linuxfoundation.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mcgrof@kernel.org \
--cc=minchan@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.