evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

CDC-NCM: handle incomplete transfer of MTU

Browse source 
[ Upstream commit 332f989a3b0041b810836c5c3747e59aad7e9d0b ]

A malicious device may give half an answer when asked
for its MTU. The driver will proceed after this with
a garbage MTU. Anything but a complete answer must be treated
as an error.

V2: used sizeof as request by Alexander

Reported-and-tested-by: syzbot+0631d878823ce2411636@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Oliver Neukum 2019-11-07 09:48:01 +01:00 • committed by Greg Kroah-Hartman
parent 1b8629e7c9
commit 7ff40996bb
1 changed files with 3 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/net/usb/cdc_ncm.c
View file

@ -533,8 +533,8 @@ static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
/* read current mtu value from device */
err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
0, iface_no, &max_datagram_size, 2);
if (err < 0) {
0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
if (err < sizeof(max_datagram_size)) {
dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
goto out;
}
@ -545,7 +545,7 @@ static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
0, iface_no, &max_datagram_size, 2);
0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
if (err < 0)
dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");