[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20211018132326.935583884@linuxfoundation.org>
Date: Mon, 18 Oct 2021 15:24:19 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Jonathan Bell <jonathan@...pberrypi.com>,
Mathias Nyman <mathias.nyman@...ux.intel.com>
Subject: [PATCH 4.19 12/50] xhci: guard accesses to ep_state in xhci_endpoint_reset()
From: Jonathan Bell <jonathan@...pberrypi.com>
commit a01ba2a3378be85538e0183ae5367c1bc1d5aaf3 upstream.
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.
Fixes: f5249461b504 ("xhci: Clear the host side toggle manually when endpoint is soft reset")
Cc: stable@...r.kernel.org
Signed-off-by: Jonathan Bell <jonathan@...pberrypi.com>
Signed-off-by: Mathias Nyman <mathias.nyman@...ux.intel.com>
Link: https://lore.kernel.org/r/20211008092547.3996295-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
drivers/usb/host/xhci.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3093,10 +3093,13 @@ static void xhci_endpoint_reset(struct u
ep = &vdev->eps[ep_index];
/* 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))
@@ -3182,8 +3185,10 @@ static void xhci_endpoint_reset(struct u
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,
Powered by blists - more mailing lists