diff options
| author | Oliver Neukum <oneukum@suse.com> | 2016-03-15 10:14:04 +0100 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2016-04-11 16:44:04 +0200 |
| commit | f475db149d75bf100084a813ce9e1e9f4fa508e7 (patch) | |
| tree | a560cad1b8f4a5b4b5d47e7a4f6211a35305a1ee /drivers/usb | |
| parent | 0db3d20b766d627cf60f61c9d2c3d92dc3359fa9 (diff) | |
| download | lwn-f475db149d75bf100084a813ce9e1e9f4fa508e7.tar.gz lwn-f475db149d75bf100084a813ce9e1e9f4fa508e7.zip | |
USB: cdc-acm: more sanity checking
commit 8835ba4a39cf53f705417b3b3a94eb067673f2c9 upstream.
An attack has become available which pretends to be a quirky
device circumventing normal sanity checks and crashes the kernel
by an insufficient number of interfaces. This patch adds a check
to the code path for quirky devices.
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index c0ed832d8ad5..ba6b978d9de4 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -989,6 +989,9 @@ static int acm_probe(struct usb_interface *intf, if (quirks == NO_UNION_NORMAL) { data_interface = usb_ifnum_to_if(usb_dev, 1); control_interface = usb_ifnum_to_if(usb_dev, 0); + /* we would crash */ + if (!data_interface || !control_interface) + return -ENODEV; goto skip_normal_probe; } |