USB: fix bug in initialization of interface minor numbers
Recent changes in the usbhid layer exposed a bug in usbcore. If
CONFIG_USB_DYNAMIC_MINORS is enabled then an interface may be assigned
a minor number of 0. However interfaces that aren't registered as USB
class devices also have their minor number set to 0, during
initialization. As a result usb_find_interface() may return the
wrong interface, leading to a crash.
This patch (as1418) fixes the problem by initializing every
interface's minor number to -1. It also cleans up the
usb_register_dev() function, which besides being somewhat awkwardly
written, does not unwind completely on all its error paths.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Philip J. Turmel <philip@turmel.org>
Tested-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Tested-by: Alex Riesen <raa.lkml@gmail.com>
Tested-by: Matthias Bayer <jackdachef@gmail.com>
CC: Jiri Kosina <jkosina@suse.cz>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 844683e..9f0ce7d 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1802,6 +1802,7 @@
intf->dev.groups = usb_interface_groups;
intf->dev.dma_mask = dev->dev.dma_mask;
INIT_WORK(&intf->reset_ws, __usb_queue_reset_device);
+ intf->minor = -1;
device_initialize(&intf->dev);
dev_set_name(&intf->dev, "%d-%s:%d.%d",
dev->bus->busnum, dev->devpath,