* [PATCH nf] netfilter: nft_payload: do not update layer 4 checksum when mangling fragments
@ 2022-01-05 15:26 Pablo Neira Ayuso
0 siblings, 0 replies; only message in thread
From: Pablo Neira Ayuso @ 2022-01-05 15:26 UTC (permalink / raw)
To: netfilter-devel
IP fragments do not come with the transport header, hence skip bogus
layer 4 checksum updates.
Reported-by: Steffen Weinreich <steve@weinreich.org>
Tested-by: Steffen Weinreich <steve@weinreich.org>
Fixes: 1814096980bb ("netfilter: nft_payload: layer 4 checksum adjustment for pseudoheader fields")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/nft_payload.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index bd689938a2e0..58e96a0fe0b4 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -546,6 +546,9 @@ static int nft_payload_l4csum_offset(const struct nft_pktinfo *pkt,
struct sk_buff *skb,
unsigned int *l4csum_offset)
{
+ if (pkt->fragoff)
+ return -1;
+
switch (pkt->tprot) {
case IPPROTO_TCP:
*l4csum_offset = offsetof(struct tcphdr, check);
--
2.30.2
^ permalink raw reply related [flat|nested] only message in thread
only message in thread, other threads:[~2022-01-05 15:26 UTC | newest]
Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-01-05 15:26 [PATCH nf] netfilter: nft_payload: do not update layer 4 checksum when mangling fragments Pablo Neira Ayuso
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).