From 75cc1c1fcba1987bdf3979c4289ab756c2b15742 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Wed, 31 Jul 2013 10:54:11 +0200 Subject: [PATCH] xhci: fix segfault Guest trying to reset a endpoint of a disconnected device resulted in xhci trying to dereference uport while being NULL, thereby crashing qemu. Fix that by adding a check. Drop unused dev variable while touching that code bit. Cc: qemu-stable@nongnu.org Signed-off-by: Gerd Hoffmann --- hw/usb/hcd-xhci.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c index 7cbf813696..ff5f68135c 100644 --- a/hw/usb/hcd-xhci.c +++ b/hw/usb/hcd-xhci.c @@ -1429,7 +1429,6 @@ static TRBCCode xhci_reset_ep(XHCIState *xhci, unsigned int slotid, { XHCISlot *slot; XHCIEPContext *epctx; - USBDevice *dev; trace_usb_xhci_ep_reset(slotid, epid); assert(slotid >= 1 && slotid <= xhci->numslots); @@ -1465,8 +1464,8 @@ static TRBCCode xhci_reset_ep(XHCIState *xhci, unsigned int slotid, ep |= 0x80; } - dev = xhci->slots[slotid-1].uport->dev; - if (!dev) { + if (!xhci->slots[slotid-1].uport || + !xhci->slots[slotid-1].uport->dev) { return CC_USB_TRANSACTION_ERROR; }