USB: serial: option: add interface-number sanity check to flag handling
authorJohan Hovold <johan@kernel.org>
Wed, 9 Dec 2020 10:42:21 +0000 (11:42 +0100)
committerJohan Hovold <johan@kernel.org>
Wed, 9 Dec 2020 13:54:46 +0000 (14:54 +0100)
commita251963f76fa0226d0fdf0c4f989496f18d9ae7f
treee720773da250941bb3a0b86716c4b480d8da25a0
parentdaa919196be49815e342eb79fab81852102703c2
USB: serial: option: add interface-number sanity check to flag handling

Add an interface-number sanity check before testing the device flags to
avoid relying on undefined behaviour when left shifting in case a device
uses an interface number greater than or equal to BITS_PER_LONG (i.e. 64
or 32).

Reported-by: syzbot+8881b478dad0a7971f79@syzkaller.appspotmail.com
Fixes: c3a65808f04a ("USB: serial: option: reimplement interface masking")
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
drivers/usb/serial/option.c