[PATCH 1/5] xhci: guard accesses to ep_state in xhci_endpoint_reset()
From: Mathias Nyman <hidden>
Date: 2021-10-08 09:23:16
Also in:
stable
Subsystem:
the rest, usb subsystem, usb xhci driver · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Mathias Nyman
From: Jonathan Bell <redacted> See https://github.com/raspberrypi/linux/issues/3981 Two read-modify-write cycles on ep->ep_state are not guarded by xhci->lock. Fix these. Signed-off-by: Jonathan Bell <redacted> Fixes: f5249461b504 ("xhci: Clear the host side toggle manually when endpoint is soft reset") Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman <redacted> --- drivers/usb/host/xhci.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 93c38b557afd..541fe4dcc43a 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c@@ -3214,10 +3214,13 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd, return; /* Bail out if toggle is already being cleared by a endpoint reset */ + spin_lock_irqsave(&xhci->lock, flags); if (ep->ep_state & EP_HARD_CLEAR_TOGGLE) { ep->ep_state &= ~EP_HARD_CLEAR_TOGGLE; + spin_unlock_irqrestore(&xhci->lock, flags); return; } + spin_unlock_irqrestore(&xhci->lock, flags); /* Only interrupt and bulk ep's use data toggle, USB2 spec 5.5.4-> */ if (usb_endpoint_xfer_control(&host_ep->desc) || usb_endpoint_xfer_isoc(&host_ep->desc))
@@ -3303,8 +3306,10 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd, xhci_free_command(xhci, cfg_cmd); cleanup: xhci_free_command(xhci, stop_cmd); + spin_lock_irqsave(&xhci->lock, flags); if (ep->ep_state & EP_SOFT_CLEAR_TOGGLE) ep->ep_state &= ~EP_SOFT_CLEAR_TOGGLE; + spin_unlock_irqrestore(&xhci->lock, flags); } static int xhci_check_streams_endpoint(struct xhci_hcd *xhci,
--
2.25.1