diff options
| author | Foster Snowhill <forst@pen.gy> | 2025-01-26 02:54:05 +0300 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2025-01-28 14:16:32 +0300 |
| commit | 86586dcb75cb8fd062a518aca8ee667938b91efb (patch) | |
| tree | a0efba8cea7cd3d19a4dfc94ab4da4c9317e37c1 | |
| parent | 429fa68b58cefb9aa9de27e4089637298b46b757 (diff) | |
| download | linux-86586dcb75cb8fd062a518aca8ee667938b91efb.tar.xz | |
usbnet: ipheth: use static NDP16 location in URB
Original code allowed for the start of NDP16 to be anywhere within the
URB based on the `wNdpIndex` value in NTH16. Only the start position of
NDP16 was checked, so it was possible for even the fixed-length part
of NDP16 to extend past the end of URB, leading to an out-of-bounds
read.
On iOS devices, the NDP16 header always directly follows NTH16. Rely on
and check for this specific format.
This, along with NCM-specific minimal URB length check that already
exists, will ensure that the fixed-length part of NDP16 plus a set
amount of DPEs fit within the URB.
Note that this commit alone does not fully address the OoB read.
The limit on the amount of DPEs needs to be enforced separately.
Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support")
Cc: stable@vger.kernel.org
Signed-off-by: Foster Snowhill <forst@pen.gy>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | drivers/net/usb/ipheth.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 1ff5f7076ad5..c385623596d2 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -226,15 +226,14 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) ncmh = urb->transfer_buffer; if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN) || - le16_to_cpu(ncmh->wNdpIndex) >= urb->actual_length) { + /* On iOS, NDP16 directly follows NTH16 */ + ncmh->wNdpIndex != cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16))) { dev->net->stats.rx_errors++; return retval; } - ncm0 = urb->transfer_buffer + le16_to_cpu(ncmh->wNdpIndex); - if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN) || - le16_to_cpu(ncmh->wHeaderLength) + le16_to_cpu(ncm0->wLength) >= - urb->actual_length) { + ncm0 = urb->transfer_buffer + sizeof(struct usb_cdc_ncm_nth16); + if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) { dev->net->stats.rx_errors++; return retval; } |