usb: dwc3: core: avoid NULL pointer dereference

commit 3e10a2c ("usb: dwc3: add hsphy_interface property") introduced a possible NULL pointer dereference because dwc->hsphy_interface can be NULL. In order to fix it, all we have to do is guard strncmp() against a NULL argument. Fixes: 3e10a2c ("usb: dwc3: add hsphy_interface property") Tested-by: Murali Karicheri <[email protected]> Signed-off-by: Felipe Balbi <[email protected]>
kmaincent · Jul 6, 2015 · 43cacb0 · 43cacb0
1 parent cc1e204
commit 43cacb0
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
@@ -446,10 +446,12 @@ static int dwc3_phy_setup(struct dwc3 *dwc)
 	/* Select the HS PHY interface */
 	switch (DWC3_GHWPARAMS3_HSPHY_IFC(dwc->hwparams.hwparams3)) {
 	case DWC3_GHWPARAMS3_HSPHY_IFC_UTMI_ULPI:
-		if (!strncmp(dwc->hsphy_interface, "utmi", 4)) {
+		if (dwc->hsphy_interface &&
+				!strncmp(dwc->hsphy_interface, "utmi", 4)) {
 			reg &= ~DWC3_GUSB2PHYCFG_ULPI_UTMI;
 			break;
-		} else if (!strncmp(dwc->hsphy_interface, "ulpi", 4)) {
+		} else if (dwc->hsphy_interface &&
+				!strncmp(dwc->hsphy_interface, "ulpi", 4)) {
 			reg |= DWC3_GUSB2PHYCFG_ULPI_UTMI;
 			dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 		} else {