From a18cfd715e91d2013da3dac86ce18f34a25d9e64 Mon Sep 17 00:00:00 2001 From: Li Jun Date: Fri, 18 Jun 2021 16:28:58 +0800 Subject: [PATCH] usb: chipidea: host: fix port index underflow and UBSAN complains [ Upstream commit e5d6a7c6cfae9e714a0e8ff64facd1ac68a784c6 ] If wIndex is 0 (and it often is), these calculations underflow and UBSAN complains, here resolve this by not decrementing the index when it is equal to 0, this copies the solution from commit 85e3990bea49 ("USB: EHCI: avoid undefined pointer arithmetic and placate UBSAN") Reported-by: Zhipeng Wang Signed-off-by: Li Jun Link: https://lore.kernel.org/r/1624004938-2399-1-git-send-email-jun.li@nxp.com Signed-off-by: Peter Chen Signed-off-by: Sasha Levin --- drivers/usb/chipidea/host.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c index 48e4a5ca1835..f5f56ee07729 100644 --- a/drivers/usb/chipidea/host.c +++ b/drivers/usb/chipidea/host.c @@ -233,18 +233,26 @@ static int ci_ehci_hub_control( ) { struct ehci_hcd *ehci = hcd_to_ehci(hcd); + unsigned int ports = HCS_N_PORTS(ehci->hcs_params); u32 __iomem *status_reg; - u32 temp; + u32 temp, port_index; unsigned long flags; int retval = 0; struct device *dev = hcd->self.controller; struct ci_hdrc *ci = dev_get_drvdata(dev); - status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1]; + port_index = wIndex & 0xff; + port_index -= (port_index > 0); + status_reg = &ehci->regs->port_status[port_index]; spin_lock_irqsave(&ehci->lock, flags); if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) { + if (!wIndex || wIndex > ports) { + retval = -EPIPE; + goto done; + } + temp = ehci_readl(ehci, status_reg); if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) { retval = -EPIPE; @@ -273,7 +281,7 @@ static int ci_ehci_hub_control( ehci_writel(ehci, temp, status_reg); } - set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports); + set_bit(port_index, &ehci->suspended_ports); goto done; }