usb: chipidea: host: fix NULL ptr dereference during shutdown

commit 991d5add50a5bb6ab8f12f2129f5c7487f6baaf6 upstream.

After commit b09b5224fe86 ("usb: chipidea: implement platform shutdown
callback") and commit 43a404577a93 ("usb: chipidea: host: set host to
be null after hcd is freed") a NULL pointer dereference is caused
on i.MX23 during shutdown. So ensure that role is set to CI_ROLE_END and
we finish interrupt handling before the hcd is deallocated. This avoids
the NULL pointer dereference.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Fixes: b09b5224fe86 ("usb: chipidea: implement platform shutdown callback")
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index 053bac9d983cbd7b3e4d24ee9f227ec0ba909368..887be343fcd4523d2c54c9c21be7ec2742bf0875 100644 (file)
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -185,6 +185,8 @@ static void host_stop(struct ci_hdrc *ci)
 
        if (hcd) {
                usb_remove_hcd(hcd);
+               ci->role = CI_ROLE_END;
+               synchronize_irq(ci->irq);
                usb_put_hcd(hcd);
                if (ci->platdata->reg_vbus && !ci_otg_is_fsm_mode(ci) &&
                        (ci->platdata->flags & CI_HDRC_TURN_VBUS_EARLY_ON))