From: Tong Zhang <ztong0001@gmail.com> mainline inclusion from mainline-v5.14-rc1 commit 42933c8aa14be1caa9eda41f65cde8a3a95d3e39 category: bugfix bugzilla: NA CVE: CVE-2022-0487 -------------------------------- This patch fixes the following issues: 1. memstick_free_host() will free the host, so the use of ms_dev(host) after it will be a problem. To fix this, move memstick_free_host() after when we are done with ms_dev(host). 2. In rtsx_usb_ms_drv_remove(), pm need to be disabled before we remove and free host otherwise memstick_check will be called and UAF will happen. [ 11.351173] BUG: KASAN: use-after-free in rtsx_usb_ms_drv_remove+0x94/0x140 [rtsx_usb_ms] [ 11.357077] rtsx_usb_ms_drv_remove+0x94/0x140 [rtsx_usb_ms] [ 11.357376] platform_remove+0x2a/0x50 [ 11.367531] Freed by task 298: [ 11.368537] kfree+0xa4/0x2a0 [ 11.368711] device_release+0x51/0xe0 [ 11.368905] kobject_put+0xa2/0x120 [ 11.369090] rtsx_usb_ms_drv_remove+0x8c/0x140 [rtsx_usb_ms] [ 11.369386] platform_remove+0x2a/0x50 [ 12.038408] BUG: KASAN: use-after-free in __mutex_lock.isra.0+0x3ec/0x7c0 [ 12.045432] mutex_lock+0xc9/0xd0 [ 12.046080] memstick_check+0x6a/0x578 [memstick] [ 12.046509] process_one_work+0x46d/0x750 [ 12.052107] Freed by task 297: [ 12.053115] kfree+0xa4/0x2a0 [ 12.053272] device_release+0x51/0xe0 [ 12.053463] kobject_put+0xa2/0x120 [ 12.053647] rtsx_usb_ms_drv_remove+0xc4/0x140 [rtsx_usb_ms] [ 12.053939] platform_remove+0x2a/0x50 Signed-off-by: Tong Zhang <ztong0001@gmail.com> Co-developed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20210511163944.1233295-1-ztong0001@gmail.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Conflicts: drivers/memstick/host/rtsx_usb_ms.c [yyl: rtsx_usb_ms_drv_probe() don't need to fix] Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Wang Weiyang <wangweiyang2@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/memstick/host/rtsx_usb_ms.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/memstick/host/rtsx_usb_ms.c b/drivers/memstick/host/rtsx_usb_ms.c index 4f64563df7ded..aee62f0618c70 100644 --- a/drivers/memstick/host/rtsx_usb_ms.c +++ b/drivers/memstick/host/rtsx_usb_ms.c @@ -798,9 +798,6 @@ static int rtsx_usb_ms_drv_remove(struct platform_device *pdev) mutex_unlock(&host->host_mutex); wait_for_completion(&host->detect_ms_exit); - memstick_remove_host(msh); - memstick_free_host(msh); - /* Balance possible unbalanced usage count * e.g. unconditional module removal */ @@ -808,10 +805,11 @@ static int rtsx_usb_ms_drv_remove(struct platform_device *pdev) pm_runtime_put(ms_dev(host)); pm_runtime_disable(&pdev->dev); - platform_set_drvdata(pdev, NULL); - + memstick_remove_host(msh); dev_dbg(&(pdev->dev), ": Realtek USB Memstick controller has been removed\n"); + memstick_free_host(msh); + platform_set_drvdata(pdev, NULL); return 0; } -- 2.25.1