memstick: r592: Fix UAF bug in r592_remove due to race condition

mainline inclusion
from mainline-v6.4-rc1
commit 63264422
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7EK74
CVE: CVE-2023-3141

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=632644227850

--------------------------------

In r592_probe, dev->detect_timer was bound with r592_detect_timer.
In r592_irq function, the timer function will be invoked by mod_timer.

If we remove the module which will call hantro_release to make cleanup,
there may be a unfinished work. The possible sequence is as follows,
which will cause a typical UAF bug.

Fix it by canceling the work before cleanup in r592_remove.

CPU0                  CPU1

                    |r592_detect_timer
r592_remove         |
  memstick_free_host|
  put_device;       |
  kfree(host);      |
                    |
                    | queue_work
                    |   &host->media_checker //use
Signed-off-by: NZheng Wang <zyytlz.wz@163.com>
Link: https://lore.kernel.org/r/20230307164338.1246287-1-zyytlz.wz@163.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NChen Zhongjin <chenzhongjin@huawei.com>
(cherry picked from commit 24fbf41b)

drivers/memstick/host/r592.c

@@ -828,7 +828,7 @@ static void r592_remove(struct pci_dev *pdev)
 	/* Stop the processing thread.
 	That ensures that we won't take any more requests */
 	kthread_stop(dev->io_thread);
-
+	del_timer_sync(&dev->detect_timer);
 	r592_enable_device(dev, false);
 
 	while (!error && dev->req) {