[PATCH] hid: usbhid: Use flag HID_DISCONNECTED when a usb device is removed

From: Reyad Attiyat
Date: Fri Jul 25 2014 - 01:13:46 EST


Set disconnected flag in struct usbhid when a usb device
is removed. Check for disconnected flag before sending urb
requests. This prevents a kernel panic when a hid driver calls
hid_hw_request() after removing a usb device.

Signed-off-by: Reyad Attiyat <reyad.attiyat@xxxxxxxxx>
---
drivers/hid/usbhid/hid-core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 7b88f4c..c8fa957 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -536,7 +536,8 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re
int head;
struct usbhid_device *usbhid = hid->driver_data;

- if ((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN)
+ if (((hid->quirks & HID_QUIRK_NOGET) && dir == USB_DIR_IN) ||
+ test_bit(HID_DISCONNECTED, &usbhid->iofl))
return;

if (usbhid->urbout && dir == USB_DIR_OUT && report->type == HID_OUTPUT_REPORT) {
@@ -1366,6 +1367,9 @@ static void usbhid_disconnect(struct usb_interface *intf)
return;

usbhid = hid->driver_data;
+ spin_lock_irq(&usbhid->lock); /* Sync with error and led handlers */
+ set_bit(HID_DISCONNECTED, &usbhid->iofl);
+ spin_unlock_irq(&usbhid->lock);
hid_destroy_device(hid);
kfree(usbhid);
}
--
1.9.3

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