From: Zheng Wang zyytlz.wz@163.com
[ Upstream commit 63264422785021704c39b38f65a78ab9e4a186d7 ]
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: Zheng Wang zyytlz.wz@163.com Link: https://lore.kernel.org/r/20230307164338.1246287-1-zyytlz.wz@163.com Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/memstick/host/r592.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/memstick/host/r592.c b/drivers/memstick/host/r592.c index eaa2a94d18be4..dd06c18495eb6 100644 --- a/drivers/memstick/host/r592.c +++ b/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) {