[PATCH] xhci: guard accesses to ep_state in xhci_endpoint_reset()
From: Phil Elwell <hidden>
Date: 2021-08-31 16:03:13
Also in:
lkml
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> --- 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 f3dabd02382c2..902f410874e8e 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c@@ -3213,10 +3213,13 @@ 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))
@@ -3302,8 +3305,10 @@ 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,
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2.25.1