From: Oliver Neukum Date: Tue, 20 Sep 2016 13:45:42 +0000 (+0200) Subject: cdc-acm: hardening against malicious devices X-Git-Tag: v4.9-rc1~146^2~14 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=2ad9d544f2497a7bf239c34bd2b86fd19683dbb5;p=linux-2.6-block.git 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 15ffe389b86f..78f0f85bebdc 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1179,6 +1179,9 @@ static int acm_probe(struct usb_interface *intf, return -EINVAL; } + if (!intf->cur_altsetting) + return -EINVAL; + if (!buflen) { if (intf->cur_altsetting->endpoint && intf->cur_altsetting->endpoint->extralen && @@ -1232,6 +1235,8 @@ static int acm_probe(struct usb_interface *intf, 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");