This is a note to let you know that I've just added the patch titled
netfilter: nft_payload: incorrect arithmetics when fetching VLAN header bits
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netfilter-nft_payload-incorrect-arithmetics-when-fetching-vlan-header-bits.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 696e1a48b1a1b01edad542a1ef293665864a4dd0 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Wed, 11 Jan 2023 17:07:33 +0100
Subject: netfilter: nft_payload: incorrect arithmetics when fetching VLAN header bits
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
commit 696e1a48b1a1b01edad542a1ef293665864a4dd0 upstream.
If the offset + length goes over the ethernet + vlan header, then the
length is adjusted to copy the bytes that are within the boundaries of
the vlan_ethhdr scratchpad area. The remaining bytes beyond ethernet +
vlan header are copied directly from the skbuff data area.
Fix incorrect arithmetic operator: subtract, not add, the size of the
vlan header in case of double-tagged packets to adjust the length
accordingly to address CVE-2023-0179.
Reported-by: Davide Ornaghi <d.ornaghi97@xxxxxxxxx>
Fixes: f6ae9f120dad ("netfilter: nft_payload: add C-VLAN support")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nft_payload.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -63,7 +63,7 @@ nft_payload_copy_vlan(u32 *d, const stru
return false;
if (offset + len > VLAN_ETH_HLEN + vlan_hlen)
- ethlen -= offset + len - VLAN_ETH_HLEN + vlan_hlen;
+ ethlen -= offset + len - VLAN_ETH_HLEN - vlan_hlen;
memcpy(dst_u8, vlanh + offset - vlan_hlen, ethlen);
Patches currently in stable-queue which might be from pablo@xxxxxxxxxxxxx are
queue-5.15/netfilter-nft_payload-incorrect-arithmetics-when-fetching-vlan-header-bits.patch
