Fixes for 4.19

Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/queue-4.19/series b/queue-4.19/series
index 26add73e153038ca32ba369be7ec9a7ee17bda15..c59499222bc20d7bd100a35760c186a6700a57e3 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -15,3 +15,4 @@ staging-rtl8712-fix-use-after-free-bugs.patch
 vt-clear-selection-before-changing-the-font.patch
 usb-serial-ftdi_sio-add-omron-cs1w-cif31-device-id.patch
 binder-fix-uaf-of-ref-proc-caused-by-race-condition.patch
+usb-dwc3-qcom-fix-use-after-free-on-runtime-pm-wakeu.patch

diff --git a/queue-4.19/usb-dwc3-qcom-fix-use-after-free-on-runtime-pm-wakeu.patch b/queue-4.19/usb-dwc3-qcom-fix-use-after-free-on-runtime-pm-wakeu.patch
new file mode 100644 (file)
index 0000000..a37ca2d
--- /dev/null
+++ b/queue-4.19/usb-dwc3-qcom-fix-use-after-free-on-runtime-pm-wakeu.patch
@@ -0,0 +1,82 @@
+From bbacb2bb921f81d43278c35bbd9060d7d41eaf67 Mon Sep 17 00:00:00 2001
+From: Sasha Levin <sashal@kernel.org>
+Date: Thu, 4 Aug 2022 17:09:56 +0200
+Subject: usb: dwc3: qcom: fix use-after-free on runtime-PM wakeup
+
+From: Johan Hovold <johan+linaro@kernel.org>
+
+[ Upstream commit a872ab303d5ddd4c965f9cd868677781a33ce35a ]
+
+The Qualcomm dwc3 runtime-PM implementation checks the xhci
+platform-device pointer in the wakeup-interrupt handler to determine
+whether the controller is in host mode and if so triggers a resume.
+
+After a role switch in OTG mode the xhci platform-device would have been
+freed and the next wakeup from runtime suspend would access the freed
+memory.
+
+Note that role switching is executed from a freezable workqueue, which
+guarantees that the pointer is stable during suspend.
+
+Also note that runtime PM has been broken since commit 2664deb09306
+("usb: dwc3: qcom: Honor wakeup enabled/disabled state"), which
+incidentally also prevents this issue from being triggered.
+
+Fixes: a4333c3a6ba9 ("usb: dwc3: Add Qualcomm DWC3 glue driver")
+Cc: stable@vger.kernel.org      # 4.18
+Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
+Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
+Link: https://lore.kernel.org/r/20220804151001.23612-5-johan+linaro@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ drivers/usb/dwc3/dwc3-qcom.c | 14 +++++++++++++-
+ drivers/usb/dwc3/host.c      |  1 +
+ 2 files changed, 14 insertions(+), 1 deletion(-)
+
+diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
+index 5bb5384f36125..9d5320562e81f 100644
+--- a/drivers/usb/dwc3/dwc3-qcom.c
++++ b/drivers/usb/dwc3/dwc3-qcom.c
+@@ -173,6 +173,14 @@ static int dwc3_qcom_register_extcon(struct dwc3_qcom *qcom)
+       return 0;
+ }
+ 
++/* Only usable in contexts where the role can not change. */
++static bool dwc3_qcom_is_host(struct dwc3_qcom *qcom)
++{
++      struct dwc3 *dwc = platform_get_drvdata(qcom->dwc3);
++
++      return dwc->xhci;
++}
++
+ static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
+ {
+       if (qcom->hs_phy_irq) {
+@@ -280,7 +288,11 @@ static irqreturn_t qcom_dwc3_resume_irq(int irq, void *data)
+       if (qcom->pm_suspended)
+               return IRQ_HANDLED;
+ 
+-      if (dwc->xhci)
++      /*
++       * This is safe as role switching is done from a freezable workqueue
++       * and the wakeup interrupts are disabled as part of resume.
++       */
++      if (dwc3_qcom_is_host(qcom))
+               pm_runtime_resume(&dwc->xhci->dev);
+ 
+       return IRQ_HANDLED;
+diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
+index 1a3878a3be78f..124e9f80dccd8 100644
+--- a/drivers/usb/dwc3/host.c
++++ b/drivers/usb/dwc3/host.c
+@@ -142,4 +142,5 @@ void dwc3_host_exit(struct dwc3 *dwc)
+       phy_remove_lookup(dwc->usb3_generic_phy, "usb3-phy",
+                         dev_name(dwc->dev));
+       platform_device_unregister(dwc->xhci);
++      dwc->xhci = NULL;
+ }
+-- 
+2.35.1
+