usb: xhci: Handle error condition in xhci_stop_device()

xhci_stop_device() calls xhci_queue_stop_endpoint() multiple times
without checking the return value. xhci_queue_stop_endpoint() can
return error if the HC is already halted or unable to queue commands.
This can cause a deadlock condition as xhci_stop_device() would
end up waiting indefinitely for a completion for the command that
didn't get queued. Fix this by checking the return value and bailing
out of xhci_stop_device() in case of error. This patch happens to fix
potential memory leaks of the allocated command structures as well.

Fixes: c311e391a7 ("xhci: rework command timeout and cancellation,")
Cc: <stable@vger.kernel.org>
Signed-off-by: Mayank Rana <mrana@codeaurora.org>
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mayank Rana 2017-10-06 17:45:30 +03:00 committed by Greg Kroah-Hartman
parent 810a624bd1
commit b3207c65df

View file

@ -420,14 +420,25 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
GFP_NOWAIT);
if (!command) {
spin_unlock_irqrestore(&xhci->lock, flags);
xhci_free_command(xhci, cmd);
return -ENOMEM;
ret = -ENOMEM;
goto cmd_cleanup;
}
ret = xhci_queue_stop_endpoint(xhci, command, slot_id,
i, suspend);
if (ret) {
spin_unlock_irqrestore(&xhci->lock, flags);
xhci_free_command(xhci, command);
goto cmd_cleanup;
}
xhci_queue_stop_endpoint(xhci, command, slot_id, i,
suspend);
}
}
xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend);
ret = xhci_queue_stop_endpoint(xhci, cmd, slot_id, 0, suspend);
if (ret) {
spin_unlock_irqrestore(&xhci->lock, flags);
goto cmd_cleanup;
}
xhci_ring_cmd_db(xhci);
spin_unlock_irqrestore(&xhci->lock, flags);
@ -439,6 +450,8 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n");
ret = -ETIME;
}
cmd_cleanup:
xhci_free_command(xhci, cmd);
return ret;
}