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usb: hub: Fix locking issues with address0_mutex

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Fix the circular lock dependency and unbalanced unlock of addess0_mutex
introduced when fixing an address0_mutex enumeration retry race in commit
ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race")

Make sure locking order between port_dev->status_lock and address0_mutex
is correct, and that address0_mutex is not unlocked in hub_port_connect
"done:" codepath which may be reached without locking address0_mutex

Fixes: 6ae6dc22d2 ("usb: hub: Fix usb enumeration issue due to address0 race")
Cc: <stable@vger.kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20211123101656.1113518-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathias Nyman 2021-11-23 12:16:56 +02:00 committed by Greg Kroah-Hartman
parent d4d2e5329a
commit 6cca13de26
1 changed files with 12 additions and 8 deletions
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20
drivers/usb/core/hub.c
View file

@ -5188,6 +5188,7 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
struct usb_port *port_dev = hub->ports[port1 - 1];
struct usb_device *udev = port_dev->child;
static int unreliable_port = -1;
bool retry_locked;
/* Disconnect any existing devices under this port */
if (udev) {
@ -5244,10 +5245,10 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
status = 0;
mutex_lock(hcd->address0_mutex);
for (i = 0; i < PORT_INIT_TRIES; i++) {
usb_lock_port(port_dev);
mutex_lock(hcd->address0_mutex);
retry_locked = true;
/* reallocate for each attempt, since references
* to the previous one can escape in various ways
*/
@ -5255,6 +5256,8 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
if (!udev) {
dev_err(&port_dev->dev,
"couldn't allocate usb_device\n");
mutex_unlock(hcd->address0_mutex);
usb_unlock_port(port_dev);
goto done;
}
@ -5276,13 +5279,13 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
}
/* reset (non-USB 3.0 devices) and get descriptor */
usb_lock_port(port_dev);
status = hub_port_init(hub, udev, port1, i);
usb_unlock_port(port_dev);
if (status < 0)
goto loop;
mutex_unlock(hcd->address0_mutex);
usb_unlock_port(port_dev);
retry_locked = false;
if (udev->quirks & USB_QUIRK_DELAY_INIT)
msleep(2000);
@ -5372,11 +5375,14 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
loop_disable:
hub_port_disable(hub, port1, 1);
mutex_lock(hcd->address0_mutex);
loop:
usb_ep0_reinit(udev);
release_devnum(udev);
hub_free_dev(udev);
if (retry_locked) {
mutex_unlock(hcd->address0_mutex);
usb_unlock_port(port_dev);
}
usb_put_dev(udev);
if ((status == -ENOTCONN) || (status == -ENOTSUPP))
break;
@ -5399,8 +5405,6 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
}
done:
mutex_unlock(hcd->address0_mutex);
hub_port_disable(hub, port1, 1);
if (hcd->driver->relinquish_port && !hub->hdev->parent) {
if (status != -ENOTCONN && status != -ENODEV)