4.9-stable review patch. If anyone has any objections, please let me know.
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From: Mathias Nyman mathias.nyman@linux.intel.com
[ Upstream commit a400efe455f7b61ac9a801ac8d0d01f8c8d82dd5 ]
set udev->slot_id to zero when disabling and freeing the xhci slot. Prevents usb core from calling xhci with a stale slot id.
xHC controller may be reset during resume to recover from some error. All slots are unusable as they are disabled and freed. xhci driver starts slot enumeration again from 1 in the order they are enabled. In the worst case a stale udev->slot_id for one device matches a newly enabled slot_id for a different device, causing us to perform a action on the wrong device.
Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci-mem.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -975,6 +975,8 @@ void xhci_free_virt_device(struct xhci_h if (dev->out_ctx) xhci_free_container_ctx(xhci, dev->out_ctx);
+ if (dev->udev && dev->udev->slot_id) + dev->udev->slot_id = 0; kfree(xhci->devs[slot_id]); xhci->devs[slot_id] = NULL; }