cdc-acm: hardening against malicious devices
This should fix the last holes against malicious devices
still open in cdc-acm. It cannot go into stable due to
the introduction of the common parser.
The fix for stable already merged also covers the problems this patch
fixes.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 15ffe38..78f0f85 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1179,6 +1179,9 @@
return -EINVAL;
}
+ if (!intf->cur_altsetting)
+ return -EINVAL;
+
if (!buflen) {
if (intf->cur_altsetting->endpoint &&
intf->cur_altsetting->endpoint->extralen &&
@@ -1232,6 +1235,8 @@
dev_dbg(&intf->dev, "no interfaces\n");
return -ENODEV;
}
+ if (!data_interface->cur_altsetting || !control_interface->cur_altsetting)
+ return -ENODEV;
if (data_intf_num != call_intf_num)
dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");