[PATCH 3.18 19/45] usb: usbip: Fix possible deadlocks reported by lockdep

From: Greg Kroah-Hartman
Date: Thu Feb 15 2018 - 13:55:27 EST

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Andrew Goodbody <andrew.goodbody@xxxxxxxxxxxxxx>

commit 21619792d1eca7e772ca190ba68588e57f29595b upstream.

Change spin_lock calls to spin_lock_irqsave to prevent
attmpted recursive lock taking in interrupt context.

This patch fixes Bug 109351
https://bugzilla.kernel.org/show_bug.cgi?id=109351

Signed-off-by: Andrew Goodbody <andrew.goodbody@xxxxxxxxxxxxxx>
Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/usbip/usbip_event.c | 5 +-
drivers/usb/usbip/vhci_hcd.c | 88 +++++++++++++++++++++++-----------------
drivers/usb/usbip/vhci_rx.c | 30 +++++++------
drivers/usb/usbip/vhci_sysfs.c | 19 +++++---
drivers/usb/usbip/vhci_tx.c | 14 +++---
5 files changed, 91 insertions(+), 65 deletions(-)

--- a/drivers/usb/usbip/usbip_event.c
+++ b/drivers/usb/usbip/usbip_event.c
@@ -117,11 +117,12 @@ EXPORT_SYMBOL_GPL(usbip_event_add);
int usbip_event_happened(struct usbip_device *ud)
{
int happened = 0;
+ unsigned long flags;

- spin_lock(&ud->lock);
+ spin_lock_irqsave(&ud->lock, flags);
if (ud->event != 0)
happened = 1;
- spin_unlock(&ud->lock);
+ spin_unlock_irqrestore(&ud->lock, flags);

return happened;
}
--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -121,9 +121,11 @@ static void dump_port_status_diff(u32 pr

void rh_port_connect(int rhport, enum usb_device_speed speed)
{
+ unsigned long flags;
+
usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
| (1 << USB_PORT_FEAT_C_CONNECTION);
@@ -139,22 +141,24 @@ void rh_port_connect(int rhport, enum us
break;
}

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
}

static void rh_port_disconnect(int rhport)
{
+ unsigned long flags;
+
usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
the_controller->port_status[rhport] |=
(1 << USB_PORT_FEAT_C_CONNECTION);

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
}

@@ -182,13 +186,14 @@ static int vhci_hub_status(struct usb_hc
int retval;
int rhport;
int changed = 0;
+ unsigned long flags;

retval = DIV_ROUND_UP(VHCI_NPORTS + 1, 8);
memset(buf, 0, retval);

vhci = hcd_to_vhci(hcd);

- spin_lock(&vhci->lock);
+ spin_lock_irqsave(&vhci->lock, flags);
if (!HCD_HW_ACCESSIBLE(hcd)) {
usbip_dbg_vhci_rh("hw accessible flag not on?\n");
goto done;
@@ -209,7 +214,7 @@ static int vhci_hub_status(struct usb_hc
usb_hcd_resume_root_hub(hcd);

done:
- spin_unlock(&vhci->lock);
+ spin_unlock_irqrestore(&vhci->lock, flags);
return changed ? retval : 0;
}

@@ -230,6 +235,7 @@ static int vhci_hub_control(struct usb_h
struct vhci_hcd *dum;
int retval = 0;
int rhport;
+ unsigned long flags;

u32 prev_port_status[VHCI_NPORTS];

@@ -248,7 +254,7 @@ static int vhci_hub_control(struct usb_h

dum = hcd_to_vhci(hcd);

- spin_lock(&dum->lock);
+ spin_lock_irqsave(&dum->lock, flags);

/* store old status and compare now and old later */
if (usbip_dbg_flag_vhci_rh) {
@@ -402,7 +408,7 @@ static int vhci_hub_control(struct usb_h
}
usbip_dbg_vhci_rh(" bye\n");

- spin_unlock(&dum->lock);
+ spin_unlock_irqrestore(&dum->lock, flags);

return retval;
}
@@ -425,6 +431,7 @@ static void vhci_tx_urb(struct urb *urb)
{
struct vhci_device *vdev = get_vdev(urb->dev);
struct vhci_priv *priv;
+ unsigned long flags;

if (!vdev) {
pr_err("could not get virtual device");
@@ -437,7 +444,7 @@ static void vhci_tx_urb(struct urb *urb)
return;
}

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);

priv->seqnum = atomic_inc_return(&the_controller->seqnum);
if (priv->seqnum == 0xffff)
@@ -451,7 +458,7 @@ static void vhci_tx_urb(struct urb *urb)
list_add_tail(&priv->list, &vdev->priv_tx);

wake_up(&vdev->waitq_tx);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);
}

static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
@@ -460,6 +467,7 @@ static int vhci_urb_enqueue(struct usb_h
struct device *dev = &urb->dev->dev;
int ret = 0;
struct vhci_device *vdev;
+ unsigned long flags;

usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
hcd, urb, mem_flags);
@@ -467,11 +475,11 @@ static int vhci_urb_enqueue(struct usb_h
/* patch to usb_sg_init() is in 2.5.60 */
BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

if (urb->status != -EINPROGRESS) {
dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
return urb->status;
}

@@ -483,7 +491,7 @@ static int vhci_urb_enqueue(struct usb_h
vdev->ud.status == VDEV_ST_ERROR) {
dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
spin_unlock(&vdev->ud.lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
return -ENODEV;
}
spin_unlock(&vdev->ud.lock);
@@ -558,14 +566,14 @@ static int vhci_urb_enqueue(struct usb_h

out:
vhci_tx_urb(urb);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

return 0;

no_need_xmit:
usb_hcd_unlink_urb_from_ep(hcd, urb);
no_need_unlink:
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
return ret;
}
@@ -620,16 +628,17 @@ static int vhci_urb_dequeue(struct usb_h
{
struct vhci_priv *priv;
struct vhci_device *vdev;
+ unsigned long flags;

pr_info("dequeue a urb %p\n", urb);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

priv = urb->hcpriv;
if (!priv) {
/* URB was never linked! or will be soon given back by
* vhci_rx. */
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
return 0;
}

@@ -638,7 +647,7 @@ static int vhci_urb_dequeue(struct usb_h

ret = usb_hcd_check_unlink_urb(hcd, urb, status);
if (ret) {
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
return ret;
}
}
@@ -666,10 +675,10 @@ static int vhci_urb_dequeue(struct usb_h

usb_hcd_unlink_urb_from_ep(hcd, urb);

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
urb->status);
- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

} else {
/* tcp connection is alive */
@@ -681,7 +690,7 @@ static int vhci_urb_dequeue(struct usb_h
unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
if (!unlink) {
spin_unlock(&vdev->priv_lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
return -ENOMEM;
}
@@ -702,7 +711,7 @@ static int vhci_urb_dequeue(struct usb_h
spin_unlock(&vdev->priv_lock);
}

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usbip_dbg_vhci_hc("leave\n");
return 0;
@@ -711,8 +720,9 @@ static int vhci_urb_dequeue(struct usb_h
static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
{
struct vhci_unlink *unlink, *tmp;
+ unsigned long flags;

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);
spin_lock(&vdev->priv_lock);

list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
@@ -746,19 +756,19 @@ static void vhci_device_unlink_cleanup(s
list_del(&unlink->list);

spin_unlock(&vdev->priv_lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
urb->status);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);
spin_lock(&vdev->priv_lock);

kfree(unlink);
}

spin_unlock(&vdev->priv_lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
}

/*
@@ -825,8 +835,9 @@ static void vhci_shutdown_connection(str
static void vhci_device_reset(struct usbip_device *ud)
{
struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
+ unsigned long flags;

- spin_lock(&ud->lock);
+ spin_lock_irqsave(&ud->lock, flags);

vdev->speed = 0;
vdev->devid = 0;
@@ -841,14 +852,16 @@ static void vhci_device_reset(struct usb
}
ud->status = VDEV_ST_NULL;

- spin_unlock(&ud->lock);
+ spin_unlock_irqrestore(&ud->lock, flags);
}

static void vhci_device_unusable(struct usbip_device *ud)
{
- spin_lock(&ud->lock);
+ unsigned long flags;
+
+ spin_lock_irqsave(&ud->lock, flags);
ud->status = VDEV_ST_ERROR;
- spin_unlock(&ud->lock);
+ spin_unlock_irqrestore(&ud->lock, flags);
}

static void vhci_device_init(struct vhci_device *vdev)
@@ -938,12 +951,13 @@ static int vhci_get_frame_number(struct
static int vhci_bus_suspend(struct usb_hcd *hcd)
{
struct vhci_hcd *vhci = hcd_to_vhci(hcd);
+ unsigned long flags;

dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);

- spin_lock(&vhci->lock);
+ spin_lock_irqsave(&vhci->lock, flags);
hcd->state = HC_STATE_SUSPENDED;
- spin_unlock(&vhci->lock);
+ spin_unlock_irqrestore(&vhci->lock, flags);

return 0;
}
@@ -952,15 +966,16 @@ static int vhci_bus_resume(struct usb_hc
{
struct vhci_hcd *vhci = hcd_to_vhci(hcd);
int rc = 0;
+ unsigned long flags;

dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);

- spin_lock(&vhci->lock);
+ spin_lock_irqsave(&vhci->lock, flags);
if (!HCD_HW_ACCESSIBLE(hcd))
rc = -ESHUTDOWN;
else
hcd->state = HC_STATE_RUNNING;
- spin_unlock(&vhci->lock);
+ spin_unlock_irqrestore(&vhci->lock, flags);

return rc;
}
@@ -1058,17 +1073,18 @@ static int vhci_hcd_suspend(struct platf
int rhport = 0;
int connected = 0;
int ret = 0;
+ unsigned long flags;

hcd = platform_get_drvdata(pdev);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
if (the_controller->port_status[rhport] &
USB_PORT_STAT_CONNECTION)
connected += 1;

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

if (connected > 0) {
dev_info(&pdev->dev,
--- a/drivers/usb/usbip/vhci_rx.c
+++ b/drivers/usb/usbip/vhci_rx.c
@@ -72,10 +72,11 @@ static void vhci_recv_ret_submit(struct
{
struct usbip_device *ud = &vdev->ud;
struct urb *urb;
+ unsigned long flags;

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);
urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

if (!urb) {
pr_err("cannot find a urb of seqnum %u\n", pdu->base.seqnum);
@@ -104,9 +105,9 @@ static void vhci_recv_ret_submit(struct

usbip_dbg_vhci_rx("now giveback urb %p\n", urb);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);
usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);

@@ -117,8 +118,9 @@ static struct vhci_unlink *dequeue_pendi
struct usbip_header *pdu)
{
struct vhci_unlink *unlink, *tmp;
+ unsigned long flags;

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);

list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
pr_info("unlink->seqnum %lu\n", unlink->seqnum);
@@ -127,12 +129,12 @@ static struct vhci_unlink *dequeue_pendi
unlink->seqnum);
list_del(&unlink->list);

- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);
return unlink;
}
}

- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

return NULL;
}
@@ -142,6 +144,7 @@ static void vhci_recv_ret_unlink(struct
{
struct vhci_unlink *unlink;
struct urb *urb;
+ unsigned long flags;

usbip_dump_header(pdu);

@@ -152,9 +155,9 @@ static void vhci_recv_ret_unlink(struct
return;
}

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);
urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

if (!urb) {
/*
@@ -171,9 +174,9 @@ static void vhci_recv_ret_unlink(struct
urb->status = pdu->u.ret_unlink.status;
pr_info("urb->status %d\n", urb->status);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);
usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
urb->status);
@@ -185,10 +188,11 @@ static void vhci_recv_ret_unlink(struct
static int vhci_priv_tx_empty(struct vhci_device *vdev)
{
int empty = 0;
+ unsigned long flags;

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);
empty = list_empty(&vdev->priv_rx);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

return empty;
}
--- a/drivers/usb/usbip/vhci_sysfs.c
+++ b/drivers/usb/usbip/vhci_sysfs.c
@@ -32,10 +32,11 @@ static ssize_t status_show(struct device
{
char *s = out;
int i = 0;
+ unsigned long flags;

BUG_ON(!the_controller || !out);

- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

/*
* output example:
@@ -73,7 +74,7 @@ static ssize_t status_show(struct device
spin_unlock(&vdev->ud.lock);
}

- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

return out - s;
}
@@ -83,11 +84,12 @@ static DEVICE_ATTR_RO(status);
static int vhci_port_disconnect(__u32 rhport)
{
struct vhci_device *vdev;
+ unsigned long flags;

usbip_dbg_vhci_sysfs("enter\n");

/* lock */
- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);

vdev = port_to_vdev(rhport);

@@ -97,14 +99,14 @@ static int vhci_port_disconnect(__u32 rh

/* unlock */
spin_unlock(&vdev->ud.lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

return -EINVAL;
}

/* unlock */
spin_unlock(&vdev->ud.lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);

@@ -180,6 +182,7 @@ static ssize_t store_attach(struct devic
int sockfd = 0;
__u32 rhport = 0, devid = 0, speed = 0;
int err;
+ unsigned long flags;

/*
* @rhport: port number of vhci_hcd
@@ -205,14 +208,14 @@ static ssize_t store_attach(struct devic
/* now need lock until setting vdev status as used */

/* begin a lock */
- spin_lock(&the_controller->lock);
+ spin_lock_irqsave(&the_controller->lock, flags);
vdev = port_to_vdev(rhport);
spin_lock(&vdev->ud.lock);

if (vdev->ud.status != VDEV_ST_NULL) {
/* end of the lock */
spin_unlock(&vdev->ud.lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);

sockfd_put(socket);

@@ -231,7 +234,7 @@ static ssize_t store_attach(struct devic
vdev->ud.status = VDEV_ST_NOTASSIGNED;

spin_unlock(&vdev->ud.lock);
- spin_unlock(&the_controller->lock);
+ spin_unlock_irqrestore(&the_controller->lock, flags);
/* end the lock */

vdev->ud.tcp_rx = kthread_get_run(vhci_rx_loop, &vdev->ud, "vhci_rx");
--- a/drivers/usb/usbip/vhci_tx.c
+++ b/drivers/usb/usbip/vhci_tx.c
@@ -47,16 +47,17 @@ static void setup_cmd_submit_pdu(struct
static struct vhci_priv *dequeue_from_priv_tx(struct vhci_device *vdev)
{
struct vhci_priv *priv, *tmp;
+ unsigned long flags;

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);

list_for_each_entry_safe(priv, tmp, &vdev->priv_tx, list) {
list_move_tail(&priv->list, &vdev->priv_rx);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);
return priv;
}

- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

return NULL;
}
@@ -136,16 +137,17 @@ static int vhci_send_cmd_submit(struct v
static struct vhci_unlink *dequeue_from_unlink_tx(struct vhci_device *vdev)
{
struct vhci_unlink *unlink, *tmp;
+ unsigned long flags;

- spin_lock(&vdev->priv_lock);
+ spin_lock_irqsave(&vdev->priv_lock, flags);

list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
list_move_tail(&unlink->list, &vdev->unlink_rx);
- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);
return unlink;
}

- spin_unlock(&vdev->priv_lock);
+ spin_unlock_irqrestore(&vdev->priv_lock, flags);

return NULL;
}