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e43bd67d72
upon further thought this code is still racy.
retval = usb_register_dev(usbhid->intf, &hiddev_class);
here you open a window during which open can happen
if (retval) {
err_hid("Not able to get a minor for this device.");
hid->hiddev = NULL;
kfree(hiddev);
return -1;
} else {
hid->minor = usbhid->intf->minor;
hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
and will fail because hiddev_table hasn't been updated
The obvious fix of using a mutex to guard hiddev_table doesn't work because
usb_open() and usb_register_dev() take minor_rwsem and we'd have an AB-BA
deadlock. We need a lock usb_open() also takes in the right order and that leaves
only one option, BKL. I don't like it but I see no alternative.
Once the usb_open() implements something better than lock_kernel(), we could also
do so.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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|---|---|---|
| .. | ||
| hid-core.c | ||
| hid-pidff.c | ||
| hid-quirks.c | ||
| hiddev.c | ||
| Kconfig | ||
| Makefile | ||
| usbhid.h | ||
| usbkbd.c | ||
| usbmouse.c | ||