From: Oliver Neukum Date: Thu, 7 Jan 2016 10:01:00 +0000 (+0100) Subject: cdc-acm: fix NULL pointer reference X-Git-Tag: v4.5-rc1~84^2~36 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=29c6dd591bbd592472247441de9fa694acdabae8;p=linux.git cdc-acm: fix NULL pointer reference The union descriptor must be checked. Its usage was conditional before the parser was introduced. This is important, because many RNDIS device, which also use the common parser, have bogus extra descriptors. Signed-off-by: Oliver Neukum Tested-by: Vasily Galkin Signed-off-by: David S. Miller --- diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c index 3da70bf9936a..7cba2c3759df 100644 --- a/drivers/net/usb/cdc_ether.c +++ b/drivers/net/usb/cdc_ether.c @@ -160,6 +160,12 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf) info->u = header.usb_cdc_union_desc; info->header = header.usb_cdc_header_desc; info->ether = header.usb_cdc_ether_desc; + if (!info->u) { + if (rndis) + goto skip; + else /* in that case a quirk is mandatory */ + goto bad_desc; + } /* we need a master/control interface (what we're * probed with) and a slave/data interface; union * descriptors sort this all out. @@ -256,7 +262,7 @@ int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf) goto bad_desc; } - } else if (!info->header || !info->u || (!rndis && !info->ether)) { + } else if (!info->header || (!rndis && !info->ether)) { dev_dbg(&intf->dev, "missing cdc %s%s%sdescriptor\n", info->header ? "" : "header ", info->u ? "" : "union ",