mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-12 13:55:32 +00:00
Code Issues Releases Wiki Activity

netfilter: nft_exthdr: Search chunks in SCTP packets only

Browse source 
Since user space does not generate a payload dependency, plain sctp
chunk matches cause searching in non-SCTP packets, too. Avoid this
potential mis-interpretation of packet data by checking pkt->tprot.

Fixes: 133dc203d7 ("netfilter: nft_exthdr: Support SCTP chunks")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Phil Sutter 2021-06-11 19:06:45 +02:00 committed by Pablo Neira Ayuso
parent c765449591
commit 5acc44f394
1 changed files with 4 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
net/netfilter/nft_exthdr.c
View file

@ -312,6 +312,9 @@ static void nft_exthdr_sctp_eval(const struct nft_expr *expr,
const struct sctp_chunkhdr *sch;
struct sctp_chunkhdr _sch;
if (pkt->tprot != IPPROTO_SCTP)
goto err;
do {
sch = skb_header_pointer(pkt->skb, offset, sizeof(_sch), &_sch);
if (!sch || !sch->length)
@ -334,7 +337,7 @@ static void nft_exthdr_sctp_eval(const struct nft_expr *expr,
}
offset += SCTP_PAD4(ntohs(sch->length));
} while (offset < pkt->skb->len);
err:
if (priv->flags & NFT_EXTHDR_F_PRESENT)
nft_reg_store8(dest, false);
else