• Arnd Bergmann's avatar
    dvb-usb-v2: avoid use-after-free · 0cb03b6e
    Arnd Bergmann authored
    commit 00514537 upstream.
    
    I ran into a stack frame size warning because of the on-stack copy of
    the USB device structure:
    
    drivers/media/usb/dvb-usb-v2/dvb_usb_core.c: In function 'dvb_usbv2_disconnect':
    drivers/media/usb/dvb-usb-v2/dvb_usb_core.c:1029:1: error: the frame size of 1104 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
    
    Copying a device structure like this is wrong for a number of other reasons
    too aside from the possible stack overflow. One of them is that the
    dev_info() call will print the name of the device later, but AFAICT
    we have only copied a pointer to the name earlier and the actual name
    has been freed by the time it gets printed.
    
    This removes the on-stack copy of the device and instead copies the
    device name using kstrdup(). I'm ignoring the possible failure here
    as both printk() and kfree() are able to deal with NULL pointers.
    Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
    Cc: Ben Hutchings <ben@decadent.org.uk>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    0cb03b6e
dvb_usb_core.c 27.7 KB