usb: add pid check at the first of uhci_handle_td()

pid can be gotten from uhci device memory in uhci_handle_td(),
so the guest can trigger assert qemu if we get an invalid pid.
And the uhci spec 2.1.2 tells us The Host Controller sets Host
Controller Process Error bit to 1 when it detects a fatal error
and indicates that the Host Controller suffered a consistency
check failure while processing a Transfer Descriptor. An example
of a consistency check failure would be finding an illegal PID
field while processing the packet header portion of the TD.
When this error occurs, the Host Controller clears the Run/Stop
bit in the Command register to prevent further schedule execution.

We'd better to set UHCI_STS_HCPERR and kick an interrupt, check
the pid value at the first of uhci_handle_td function.

https://bugzilla.redhat.com/show_bug.cgi?id=1070027

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Message-id: 1455867238-4720-1-git-send-email-arei.gonglei@huawei.com

[ applied minor codestyle fix ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Gonglei 2016-02-19 15:33:58 +08:00 committed by Gerd Hoffmann
parent fe3c546c5f
commit 5f77e06baa

View File

@ -773,8 +773,22 @@ static int uhci_handle_td(UHCIState *s, UHCIQueue *q, uint32_t qh_addr,
bool spd;
bool queuing = (q != NULL);
uint8_t pid = td->token & 0xff;
UHCIAsync *async = uhci_async_find_td(s, td_addr);
UHCIAsync *async;
switch (pid) {
case USB_TOKEN_OUT:
case USB_TOKEN_SETUP:
case USB_TOKEN_IN:
break;
default:
/* invalid pid : frame interrupted */
s->status |= UHCI_STS_HCPERR;
s->cmd &= ~UHCI_CMD_RS;
uhci_update_irq(s);
return TD_RESULT_STOP_FRAME;
}
async = uhci_async_find_td(s, td_addr);
if (async) {
if (uhci_queue_verify(async->queue, qh_addr, td, td_addr, queuing)) {
assert(q == NULL || q == async->queue);
@ -880,11 +894,7 @@ static int uhci_handle_td(UHCIState *s, UHCIQueue *q, uint32_t qh_addr,
break;
default:
/* invalid pid : frame interrupted */
uhci_async_free(async);
s->status |= UHCI_STS_HCPERR;
uhci_update_irq(s);
return TD_RESULT_STOP_FRAME;
abort(); /* Never to execute */
}
if (async->packet.status == USB_RET_ASYNC) {