linux/drivers/usb/gadget
Nicolas Iooss 3958b79266 configfs: fix kernel infoleak through user-controlled format string
Some modules call config_item_init_type_name() and config_group_init_type_name()
with parameter "name" directly controlled by userspace.  These two
functions call config_item_set_name() with this name used as a format
string, which can be used to leak information such as content of the
stack to userspace.

For example, make_netconsole_target() in netconsole module calls
config_item_init_type_name() with the name of a newly-created directory.
This means that the following commands give some unexpected output, with
configfs mounted in /sys/kernel/config/ and on a system with a
configured eth0 ethernet interface:

    # modprobe netconsole
    # mkdir /sys/kernel/config/netconsole/target_%lx
    # echo eth0 > /sys/kernel/config/netconsole/target_%lx/dev_name
    # echo 1 > /sys/kernel/config/netconsole/target_%lx/enabled
    # echo eth0 > /sys/kernel/config/netconsole/target_%lx/dev_name
    # dmesg |tail -n1
    [  142.697668] netconsole: target (target_ffffffffc0ae8080) is
    enabled, disable to update parameters

The directory name is correct but %lx has been interpreted in the
internal item name, displayed here in the error message used by
store_dev_name() in drivers/net/netconsole.c.

To fix this, update every caller of config_item_set_name to use "%s"
when operating on untrusted input.

This issue was found using -Wformat-security gcc flag, once a __printf
attribute has been added to config_item_set_name().

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-17 16:39:53 -07:00
..
function usb: gadget: f_midi: fix error recovery path 2015-07-06 12:34:08 -05:00
legacy Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-07-04 14:13:43 -07:00
udc usb: gadget: udc: fix free_irq() after request_irq() failed 2015-07-06 12:34:08 -05:00
Kconfig usb: gadget: f_printer: fix dependencies 2015-03-24 11:35:21 -05:00
Makefile usb: gadget: use $(srctree) instead of $(PWD) for includes 2014-08-29 15:53:46 -05:00
composite.c usb: gadget: composite: Fix NULL pointer dereference 2015-07-06 12:34:08 -05:00
config.c
configfs.c configfs: fix kernel infoleak through user-controlled format string 2015-07-17 16:39:53 -07:00
configfs.h usb: gadget: OS descriptors: provide interface directory names 2014-06-19 10:06:48 -05:00
epautoconf.c usb: gadget: autoconf: net2280: match hardware and usb ep address 2015-05-26 10:40:21 -05:00
functions.c usb: gadget: add a forward pointer from usb_function to its "instance" 2013-01-21 20:52:46 +02:00
u_f.c usb: gadget: only GPL drivers in the gadget and phy framework 2014-04-21 14:07:12 -05:00
u_f.h usb: gadget: FunctionFS: share VLA macros with all usb gadget files 2014-05-14 09:37:27 -05:00
u_os_desc.h usb: gadget: u_os_desc: helper functions for accessing ext prop buffer 2014-07-10 08:36:51 -05:00
usbstring.c usb: delete non-required instances of include <linux/init.h> 2014-01-08 15:01:39 -08:00