From: Mathias Nyman mathias.nyman@linux.intel.com
commit a2bc47c43e70cf904b1af49f76d572326c08bca7 upstream.
Make sure xhci_free_dev() and xhci_kill_endpoint_urbs() do not race and cause null pointer dereference when host suddenly dies.
Usb core may call xhci_free_dev() which frees the xhci->devs[slot_id] virt device at the same time that xhci_kill_endpoint_urbs() tries to loop through all the device's endpoints, checking if there are any cancelled urbs left to give back.
hold the xhci spinlock while freeing the virt device
Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20230116142216.1141605-4-mathias.nyman@linux.intel... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3974,6 +3974,7 @@ static void xhci_free_dev(struct usb_hcd struct xhci_hcd *xhci = hcd_to_xhci(hcd); struct xhci_virt_device *virt_dev; struct xhci_slot_ctx *slot_ctx; + unsigned long flags; int i, ret;
/* @@ -4000,7 +4001,11 @@ static void xhci_free_dev(struct usb_hcd virt_dev->eps[i].ep_state &= ~EP_STOP_CMD_PENDING; virt_dev->udev = NULL; xhci_disable_slot(xhci, udev->slot_id); + + spin_lock_irqsave(&xhci->lock, flags); xhci_free_virt_device(xhci, udev->slot_id); + spin_unlock_irqrestore(&xhci->lock, flags); + }
int xhci_disable_slot(struct xhci_hcd *xhci, u32 slot_id)