4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold <johan+linaro@xxxxxxxxxx> [ Upstream commit d2d69354226de0b333d4405981f3d9c41ba8430a ] The Qualcomm dwc3 glue driver is currently accessing the driver data of the child core device during suspend and on wakeup interrupts. This is clearly a bad idea as the child may not have probed yet or could have been unbound from its driver. The first such layering violation was part of the initial version of the driver, but this was later made worse when the hack that accesses the driver data of the grand child xhci device to configure the wakeup interrupts was added. Fixing this properly is not that easily done, so add a sanity check to make sure that the child driver data is non-NULL before dereferencing it for now. Note that this relies on subtleties like the fact that driver core is making sure that the parent is not suspended while the child is probing. Reported-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Link: https://lore.kernel.org/all/20230325165217.31069-4-manivannan.sadhasivam@xxxxxxxxxx/ Fixes: d9152161b4bf ("usb: dwc3: Add Qualcomm DWC3 glue layer driver") Fixes: 6895ea55c385 ("usb: dwc3: qcom: Configure wakeup interrupts during suspend") Cc: stable@xxxxxxxxxxxxxxx # 3.18: a872ab303d5d: "usb: dwc3: qcom: fix use-after-free on runtime-PM wakeup" Cc: Sandeep Maheswaram <quic_c_sanm@xxxxxxxxxxx> Cc: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Message-ID: <20230607100540.31045-2-johan+linaro@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/dwc3/dwc3-qcom.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c index cbf9286d4c46f..0f090188e265b 100644 --- a/drivers/usb/dwc3/dwc3-qcom.c +++ b/drivers/usb/dwc3/dwc3-qcom.c @@ -176,7 +176,16 @@ static int dwc3_qcom_register_extcon(struct dwc3_qcom *qcom) /* 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); + struct dwc3 *dwc; + + /* + * FIXME: Fix this layering violation. + */ + dwc = platform_get_drvdata(qcom->dwc3); + + /* Core driver may not have probed yet. */ + if (!dwc) + return false; return dwc->xhci; } -- 2.40.1
