| Message ID | 20230313165128.3763626-1-zyytlz.wz@163.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3] usb: gadget: udc: renesas_usb3: Fix use after free bug in renesas_usb3_remove due to race condition | expand |
Hi Zheng, > From: Zheng Wang, Sent: Tuesday, March 14, 2023 1:51 AM > Subject: [PATCH v3] usb: gadget: udc: renesas_usb3: Fix use after free bug in renesas_usb3_remove due to race condition > > In renesas_usb3_probe, &usb3->role_work is bound with > renesas_usb3_role_work. renesas_usb3_start will be called > to start the work. > > If we remove the driver which will call usbhs_remove, there may be > an unfinished work. The possible sequence is as follows: > > Fix it by canceling the work before cleanup in the renesas_usb3_remove > > CPU0 CPU1 > > |renesas_usb3_role_work > renesas_usb3_remove | > usb_role_switch_unregister | > device_unregister | > kfree(sw) | > free usb3->role_sw | > | usb_role_switch_set_role > | //use usb3->role_sw > > Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") > Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> JFYI, but IIUC, - In general, my Reviewed-by is described here, not top of your Signed-off-by. - Also, you don't need to submit such this patch. If you would like to submit such a patch for some reason (ping or so on), incrementing patch version is better because original v3 [1] doesn't have my Reviewed-by tag. [1] https://lore.kernel.org/all/20230313094852.3344288-1-zyytlz.wz@163.com/ Best regards, Yoshihiro Shimoda > --- > v3: > - modify the commit message to make it clearer suggested by Yoshihiro Shimoda > v2: > - fix typo, use clearer commit message and only cancel the UAF-related work suggested by Yoshihiro Shimoda > --- > drivers/usb/gadget/udc/renesas_usb3.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c > index bee6bceafc4f..a301af66bd91 100644 > --- a/drivers/usb/gadget/udc/renesas_usb3.c > +++ b/drivers/usb/gadget/udc/renesas_usb3.c > @@ -2661,6 +2661,7 @@ static int renesas_usb3_remove(struct platform_device *pdev) > debugfs_remove_recursive(usb3->dentry); > device_remove_file(&pdev->dev, &dev_attr_role); > > + cancel_work_sync(&usb3->role_work); > usb_role_switch_unregister(usb3->role_sw); > > usb_del_gadget_udc(&usb3->gadget); > -- > 2.25.1
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> 于2023年3月14日周二 08:16写道： > > Hi Zheng, > > > From: Zheng Wang, Sent: Tuesday, March 14, 2023 1:51 AM > > Subject: [PATCH v3] usb: gadget: udc: renesas_usb3: Fix use after free bug in renesas_usb3_remove due to race condition > > > > In renesas_usb3_probe, &usb3->role_work is bound with > > renesas_usb3_role_work. renesas_usb3_start will be called > > to start the work. > > > > If we remove the driver which will call usbhs_remove, there may be > > an unfinished work. The possible sequence is as follows: > > > > Fix it by canceling the work before cleanup in the renesas_usb3_remove > > > > CPU0 CPU1 > > > > |renesas_usb3_role_work > > renesas_usb3_remove | > > usb_role_switch_unregister | > > device_unregister | > > kfree(sw) | > > free usb3->role_sw | > > | usb_role_switch_set_role > > | //use usb3->role_sw > > > > Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") > > Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > > JFYI, but IIUC, > - In general, my Reviewed-by is described here, not top of your Signed-off-by. > - Also, you don't need to submit such this patch. If you would like to submit > such a patch for some reason (ping or so on), incrementing patch version is > better because original v3 [1] doesn't have my Reviewed-by tag. > > [1] > https://lore.kernel.org/all/20230313094852.3344288-1-zyytlz.wz@163.com/ > Dear Yoshihir, Thanks for your advice. I am not familiar with the submission rules, thanks for your kind reminder. I'll keep that in mind in the future. Have a good day :) Best regards, Zheng > Best regards, > Yoshihiro Shimoda > > > --- > > v3: > > - modify the commit message to make it clearer suggested by Yoshihiro Shimoda > > v2: > > - fix typo, use clearer commit message and only cancel the UAF-related work suggested by Yoshihiro Shimoda > > --- > > drivers/usb/gadget/udc/renesas_usb3.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c > > index bee6bceafc4f..a301af66bd91 100644 > > --- a/drivers/usb/gadget/udc/renesas_usb3.c > > +++ b/drivers/usb/gadget/udc/renesas_usb3.c > > @@ -2661,6 +2661,7 @@ static int renesas_usb3_remove(struct platform_device *pdev) > > debugfs_remove_recursive(usb3->dentry); > > device_remove_file(&pdev->dev, &dev_attr_role); > > > > + cancel_work_sync(&usb3->role_work); > > usb_role_switch_unregister(usb3->role_sw); > > > > usb_del_gadget_udc(&usb3->gadget); > > -- > > 2.25.1 >
On Tue, Mar 14, 2023 at 12:51:28AM +0800, Zheng Wang wrote: > In renesas_usb3_probe, &usb3->role_work is bound with > renesas_usb3_role_work. renesas_usb3_start will be called > to start the work. > > If we remove the driver which will call usbhs_remove, there may be > an unfinished work. The possible sequence is as follows: > > Fix it by canceling the work before cleanup in the renesas_usb3_remove > > CPU0 CPU1 > > |renesas_usb3_role_work > renesas_usb3_remove | > usb_role_switch_unregister | > device_unregister | > kfree(sw) | > free usb3->role_sw | > | usb_role_switch_set_role > | //use usb3->role_sw > > Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") > Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > --- > v3: > - modify the commit message to make it clearer suggested by Yoshihiro Shimoda I see 2 v3 patches in the mailing list, which is obviously not correct. Please resubmit a v4 properly. thanks, greg k-h
Greg KH <gregkh@linuxfoundation.org> 于2023年3月16日周四 18:55写道： > > On Tue, Mar 14, 2023 at 12:51:28AM +0800, Zheng Wang wrote: > > In renesas_usb3_probe, &usb3->role_work is bound with > > renesas_usb3_role_work. renesas_usb3_start will be called > > to start the work. > > > > If we remove the driver which will call usbhs_remove, there may be > > an unfinished work. The possible sequence is as follows: > > > > Fix it by canceling the work before cleanup in the renesas_usb3_remove > > > > CPU0 CPU1 > > > > |renesas_usb3_role_work > > renesas_usb3_remove | > > usb_role_switch_unregister | > > device_unregister | > > kfree(sw) | > > free usb3->role_sw | > > | usb_role_switch_set_role > > | //use usb3->role_sw > > > > Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") > > Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> > > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > > --- > > v3: > > - modify the commit message to make it clearer suggested by Yoshihiro Shimoda > > I see 2 v3 patches in the mailing list, which is obviously not correct. > > Please resubmit a v4 properly. > Hi Greg, Thanks for your kind reminder. I'll resubmit a v4 patch later. Best regards, Zheng > thanks, > > greg k-h
diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c index bee6bceafc4f..a301af66bd91 100644 --- a/drivers/usb/gadget/udc/renesas_usb3.c +++ b/drivers/usb/gadget/udc/renesas_usb3.c @@ -2661,6 +2661,7 @@ static int renesas_usb3_remove(struct platform_device *pdev) debugfs_remove_recursive(usb3->dentry); device_remove_file(&pdev->dev, &dev_attr_role); + cancel_work_sync(&usb3->role_work); usb_role_switch_unregister(usb3->role_sw); usb_del_gadget_udc(&usb3->gadget);
In renesas_usb3_probe, &usb3->role_work is bound with renesas_usb3_role_work. renesas_usb3_start will be called to start the work. If we remove the driver which will call usbhs_remove, there may be an unfinished work. The possible sequence is as follows: Fix it by canceling the work before cleanup in the renesas_usb3_remove CPU0 CPU1 |renesas_usb3_role_work renesas_usb3_remove | usb_role_switch_unregister | device_unregister | kfree(sw) | free usb3->role_sw | | usb_role_switch_set_role | //use usb3->role_sw Fixes: 39facfa01c9f ("usb: gadget: udc: renesas_usb3: Add register of usb role switch") Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Zheng Wang <zyytlz.wz@163.com> --- v3: - modify the commit message to make it clearer suggested by Yoshihiro Shimoda v2: - fix typo, use clearer commit message and only cancel the UAF-related work suggested by Yoshihiro Shimoda --- drivers/usb/gadget/udc/renesas_usb3.c | 1 + 1 file changed, 1 insertion(+)