Merge branch 'net-usb-cdc_ncm-add-ndpoffset-to-ndp-nframes-bounds-check'

tobgaertner says:

====================
net: usb: cdc_ncm: add ndpoffset to NDP nframes bounds check

The nframes bounds check in cdc_ncm_rx_verify_ndp16() and
cdc_ncm_rx_verify_ndp32() does not account for ndpoffset,
allowing out-of-bounds reads when the NDP is placed near the
end of the NTB.
====================

Link: https://patch.msgid.link/20260314054640.2895026-1-tob.gaertner@me.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jakub Kicinski
2026-03-16 20:14:50 -07:00

View File

@@ -1656,6 +1656,7 @@ int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
struct usbnet *dev = netdev_priv(skb_in->dev);
struct usb_cdc_ncm_ndp16 *ndp16;
int ret = -EINVAL;
size_t ndp_len;
if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
netif_dbg(dev, rx_err, dev->net, "invalid NDP offset <%u>\n",
@@ -1675,8 +1676,8 @@ int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
sizeof(struct usb_cdc_ncm_dpe16));
ret--; /* we process NDP entries except for the last one */
if ((sizeof(struct usb_cdc_ncm_ndp16) +
ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
ndp_len = struct_size_t(struct usb_cdc_ncm_ndp16, dpe16, ret);
if (ndpoffset + ndp_len > skb_in->len) {
netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
ret = -EINVAL;
}
@@ -1692,6 +1693,7 @@ int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
struct usbnet *dev = netdev_priv(skb_in->dev);
struct usb_cdc_ncm_ndp32 *ndp32;
int ret = -EINVAL;
size_t ndp_len;
if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp32)) > skb_in->len) {
netif_dbg(dev, rx_err, dev->net, "invalid NDP offset <%u>\n",
@@ -1711,8 +1713,8 @@ int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
sizeof(struct usb_cdc_ncm_dpe32));
ret--; /* we process NDP entries except for the last one */
if ((sizeof(struct usb_cdc_ncm_ndp32) +
ret * (sizeof(struct usb_cdc_ncm_dpe32))) > skb_in->len) {
ndp_len = struct_size_t(struct usb_cdc_ncm_ndp32, dpe32, ret);
if (ndpoffset + ndp_len > skb_in->len) {
netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
ret = -EINVAL;
}