From 40edb52298df4c1dbbdb30b19e3ce92cf612a918 Mon Sep 17 00:00:00 2001 From: Linyu Yuan Date: Tue, 29 Jun 2021 09:51:18 +0800 Subject: [PATCH] usb: dwc3: avoid NULL access of usb_gadget_driver we found crash in dwc3_disconnect_gadget(), it is because dwc->gadget_driver become NULL before async access. 7dc0c55e9f30 ('USB: UDC core: Add udc_async_callbacks gadget op') suggest a common way to avoid such kind of issue. this change implment the callback in dwc3 and change related functions which have callback to usb gadget driver. Acked-by: Alan Stern Signed-off-by: Linyu Yuan Link: https://lore.kernel.org/r/20210629015118.7944-1-linyyuan@codeaurora.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/core.h | 1 + drivers/usb/dwc3/ep0.c | 10 ++++++---- drivers/usb/dwc3/gadget.c | 21 ++++++++++++++++----- 3 files changed, 23 insertions(+), 9 deletions(-) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index dccdf13b5f9e..5991766239ba 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1279,6 +1279,7 @@ struct dwc3 { unsigned dis_metastability_quirk:1; unsigned dis_split_quirk:1; + unsigned async_callbacks:1; u16 imod_interval; }; diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index 3cd294264372..2f9e45eed228 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -597,11 +597,13 @@ static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl) static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl) { - int ret; + int ret = -EINVAL; - spin_unlock(&dwc->lock); - ret = dwc->gadget_driver->setup(dwc->gadget, ctrl); - spin_lock(&dwc->lock); + if (dwc->async_callbacks) { + spin_unlock(&dwc->lock); + ret = dwc->gadget_driver->setup(dwc->gadget, ctrl); + spin_lock(&dwc->lock); + } return ret; } diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index af6d7f157989..45f2bc0807e8 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2585,6 +2585,16 @@ static int dwc3_gadget_vbus_draw(struct usb_gadget *g, unsigned int mA) return ret; } +static void dwc3_gadget_async_callbacks(struct usb_gadget *g, bool enable) +{ + struct dwc3 *dwc = gadget_to_dwc(g); + unsigned long flags; + + spin_lock_irqsave(&dwc->lock, flags); + dwc->async_callbacks = enable; + spin_unlock_irqrestore(&dwc->lock, flags); +} + static const struct usb_gadget_ops dwc3_gadget_ops = { .get_frame = dwc3_gadget_get_frame, .wakeup = dwc3_gadget_wakeup, @@ -2596,6 +2606,7 @@ static const struct usb_gadget_ops dwc3_gadget_ops = { .udc_set_ssp_rate = dwc3_gadget_set_ssp_rate, .get_config_params = dwc3_gadget_config_params, .vbus_draw = dwc3_gadget_vbus_draw, + .udc_async_callbacks = dwc3_gadget_async_callbacks, }; /* -------------------------------------------------------------------------- */ @@ -3231,7 +3242,7 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc, static void dwc3_disconnect_gadget(struct dwc3 *dwc) { - if (dwc->gadget_driver && dwc->gadget_driver->disconnect) { + if (dwc->async_callbacks && dwc->gadget_driver->disconnect) { spin_unlock(&dwc->lock); dwc->gadget_driver->disconnect(dwc->gadget); spin_lock(&dwc->lock); @@ -3240,7 +3251,7 @@ static void dwc3_disconnect_gadget(struct dwc3 *dwc) static void dwc3_suspend_gadget(struct dwc3 *dwc) { - if (dwc->gadget_driver && dwc->gadget_driver->suspend) { + if (dwc->async_callbacks && dwc->gadget_driver->suspend) { spin_unlock(&dwc->lock); dwc->gadget_driver->suspend(dwc->gadget); spin_lock(&dwc->lock); @@ -3249,7 +3260,7 @@ static void dwc3_suspend_gadget(struct dwc3 *dwc) static void dwc3_resume_gadget(struct dwc3 *dwc) { - if (dwc->gadget_driver && dwc->gadget_driver->resume) { + if (dwc->async_callbacks && dwc->gadget_driver->resume) { spin_unlock(&dwc->lock); dwc->gadget_driver->resume(dwc->gadget); spin_lock(&dwc->lock); @@ -3261,7 +3272,7 @@ static void dwc3_reset_gadget(struct dwc3 *dwc) if (!dwc->gadget_driver) return; - if (dwc->gadget->speed != USB_SPEED_UNKNOWN) { + if (dwc->async_callbacks && dwc->gadget->speed != USB_SPEED_UNKNOWN) { spin_unlock(&dwc->lock); usb_gadget_udc_reset(dwc->gadget, dwc->gadget_driver); spin_lock(&dwc->lock); @@ -3585,7 +3596,7 @@ static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc) * implemented. */ - if (dwc->gadget_driver && dwc->gadget_driver->resume) { + if (dwc->async_callbacks && dwc->gadget_driver->resume) { spin_unlock(&dwc->lock); dwc->gadget_driver->resume(dwc->gadget); spin_lock(&dwc->lock);