From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CF0BC433FE for ; Sat, 20 Nov 2021 03:22:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235021AbhKTDZH (ORCPT ); Fri, 19 Nov 2021 22:25:07 -0500 Received: from szxga02-in.huawei.com ([45.249.212.188]:26339 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234536AbhKTDZG (ORCPT ); Fri, 19 Nov 2021 22:25:06 -0500 Received: from dggpeml500020.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4HwzGn0tzyzbj1W; Sat, 20 Nov 2021 11:17:05 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500020.china.huawei.com (7.185.36.88) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Sat, 20 Nov 2021 11:22:02 +0800 From: Baokun Li To: , , , , CC: , , , , Hulk Robot Subject: [PATCH -next V2 1/2] sata_fsl: fix UAF in sata_fsl_port_stop when rmmod sata_fsl Date: Sat, 20 Nov 2021 11:34:19 +0800 Message-ID: <20211120033420.3762681-2-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211120033420.3762681-1-libaokun1@huawei.com> References: <20211120033420.3762681-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpeml500020.china.huawei.com (7.185.36.88) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org When the `rmmod sata_fsl.ko` command is executed in the PPC64 GNU/Linux, a bug is reported: ================================================================== BUG: Unable to handle kernel data access on read at 0x80000800805b502c Oops: Kernel access of bad area, sig: 11 [#1] NIP [c0000000000388a4] .ioread32+0x4/0x20 LR [80000000000c6034] .sata_fsl_port_stop+0x44/0xe0 [sata_fsl] Call Trace: .free_irq+0x1c/0x4e0 (unreliable) .ata_host_stop+0x74/0xd0 [libata] .release_nodes+0x330/0x3f0 .device_release_driver_internal+0x178/0x2c0 .driver_detach+0x64/0xd0 .bus_remove_driver+0x70/0xf0 .driver_unregister+0x38/0x80 .platform_driver_unregister+0x14/0x30 .fsl_sata_driver_exit+0x18/0xa20 [sata_fsl] .__se_sys_delete_module+0x1ec/0x2d0 .system_call_exception+0xfc/0x1f0 system_call_common+0xf8/0x200 ================================================================== The triggering of the BUG is shown in the following stack: driver_detach device_release_driver_internal __device_release_driver drv->remove(dev) --> platform_drv_remove/platform_remove drv->remove(dev) --> sata_fsl_remove iounmap(host_priv->hcr_base); <---- unmap kfree(host_priv); <---- free devres_release_all release_nodes dr->node.release(dev, dr->data) --> ata_host_stop ap->ops->port_stop(ap) --> sata_fsl_port_stop ioread32(hcr_base + HCONTROL) <---- UAF host->ops->host_stop(host) The iounmap(host_priv->hcr_base) and kfree(host_priv) commands should not be executed in drv->remove. These commands should be executed in host_stop after port_stop. Therefore, we move these commands to the new function sata_fsl_host_stop and bind the new function to host_stop by referring to achi. Reported-by: Hulk Robot Signed-off-by: Baokun Li --- drivers/ata/sata_fsl.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/ata/sata_fsl.c b/drivers/ata/sata_fsl.c index e5838b23c9e0..30759fd1c3a2 100644 --- a/drivers/ata/sata_fsl.c +++ b/drivers/ata/sata_fsl.c @@ -1430,12 +1430,25 @@ static struct ata_port_operations sata_fsl_ops = { .pmp_detach = sata_fsl_pmp_detach, }; +static void sata_fsl_host_stop(struct ata_host *host) +{ + struct sata_fsl_host_priv *host_priv = host->private_data; + + iounmap(host_priv->hcr_base); + kfree(host_priv); +} + +static struct ata_port_operations sata_fsl_platform_ops = { + .inherits = &sata_fsl_ops, + .host_stop = sata_fsl_host_stop, +}; + static const struct ata_port_info sata_fsl_port_info[] = { { .flags = SATA_FSL_HOST_FLAGS, .pio_mask = ATA_PIO4, .udma_mask = ATA_UDMA6, - .port_ops = &sata_fsl_ops, + .port_ops = &sata_fsl_platform_ops, }, }; @@ -1558,8 +1571,6 @@ static int sata_fsl_remove(struct platform_device *ofdev) ata_host_detach(host); irq_dispose_mapping(host_priv->irq); - iounmap(host_priv->hcr_base); - kfree(host_priv); return 0; } -- 2.31.1