From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1F806569E for ; Sun, 28 May 2023 19:13:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1042C433D2; Sun, 28 May 2023 19:13:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685301202; bh=/csMtu44to+WoMyscVxjXAwFU/W1ZJc/YakW1b+HFcg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XseC/UvXR2B7BJ+8HBu3n4VBUtxVBUgSVIfxqEYVZy583BXLejJ3+W2t7V3qtPUEd vLaYsOSV8NZCIK8P8aIoMfdMkxGYVZYoK28znEh5RQejjyY5VW/0Ek1xlDoFsvP+HG KEk4cPrzdKK6iQ3jiXChxSxxMbf11pA1X7daNHzE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zheng Wang , Ulf Hansson , Sasha Levin Subject: [PATCH 4.14 08/86] memstick: r592: Fix UAF bug in r592_remove due to race condition Date: Sun, 28 May 2023 20:09:42 +0100 Message-Id: <20230528190828.862768147@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230528190828.564682883@linuxfoundation.org> References: <20230528190828.564682883@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zheng Wang [ 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 Link: https://lore.kernel.org/r/20230307164338.1246287-1-zyytlz.wz@163.com Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin --- 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 256634ec58b63..d52c89b2a1d58 100644 --- a/drivers/memstick/host/r592.c +++ b/drivers/memstick/host/r592.c @@ -832,7 +832,7 @@ 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) { -- 2.39.2