mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-21 22:47:56 +00:00
75 lines
2.7 KiB
Diff
75 lines
2.7 KiB
Diff
|
From: Felix Fietkau <nbd@nbd.name>
|
||
|
|
Date: Thu, 26 Sep 2024 10:41:30 +0200
|
||
|
|
Subject: [PATCH] net: gso: fix tcp fraglist segmentation after pull from
|
||
|
|
frag_list
|
||
|
|
|
||
|
|
Detect tcp gso fraglist skbs with corrupted geometry (see below) and
|
||
|
|
pass these to skb_segment instead of skb_segment_list, as the first
|
||
|
|
can segment them correctly.
|
||
|
|
|
||
|
|
Valid SKB_GSO_FRAGLIST skbs
|
||
|
|
- consist of two or more segments
|
||
|
|
- the head_skb holds the protocol headers plus first gso_size
|
||
|
|
- one or more frag_list skbs hold exactly one segment
|
||
|
|
- all but the last must be gso_size
|
||
|
|
|
||
|
|
Optional datapath hooks such as NAT and BPF (bpf_skb_pull_data) can
|
||
|
|
modify these skbs, breaking these invariants.
|
||
|
|
|
||
|
|
In extreme cases they pull all data into skb linear. For TCP, this
|
||
|
|
causes a NULL ptr deref in __tcpv4_gso_segment_list_csum at
|
||
|
|
tcp_hdr(seg->next).
|
||
|
|
|
||
|
|
Detect invalid geometry due to pull, by checking head_skb size.
|
||
|
|
Don't just drop, as this may blackhole a destination. Convert to be
|
||
|
|
able to pass to regular skb_segment.
|
||
|
|
|
||
|
|
Approach and description based on a patch by Willem de Bruijn.
|
||
|
|
|
||
|
|
Link: https://lore.kernel.org/netdev/20240428142913.18666-1-shiming.cheng@mediatek.com/
|
||
|
|
Link: https://lore.kernel.org/netdev/20240922150450.3873767-1-willemdebruijn.kernel@gmail.com/
|
||
|
|
Fixes: bee88cd5bd83 ("net: add support for segmenting TCP fraglist GSO packets")
|
||
|
|
Cc: stable@vger.kernel.org
|
||
|
|
Cc: Willem de Bruijn <willemb@google.com>
|
||
|
|
Signed-off-by: Felix Fietkau <nbd@nbd.name>
|
||
|
|
---
|
||
|
|
|
||
|
|
--- a/net/ipv4/tcp_offload.c
|
||
|
|
+++ b/net/ipv4/tcp_offload.c
|
||
|
|
@@ -101,8 +101,14 @@ static struct sk_buff *tcp4_gso_segment(
|
||
|
|
if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
|
||
|
|
return ERR_PTR(-EINVAL);
|
||
|
|
|
||
|
|
- if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST)
|
||
|
|
- return __tcp4_gso_segment_list(skb, features);
|
||
|
|
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST) {
|
||
|
|
+ struct tcphdr *th = tcp_hdr(skb);
|
||
|
|
+
|
||
|
|
+ if (skb_pagelen(skb) - th->doff * 4 == skb_shinfo(skb)->gso_size)
|
||
|
|
+ return __tcp4_gso_segment_list(skb, features);
|
||
|
|
+
|
||
|
|
+ skb->ip_summed = CHECKSUM_NONE;
|
||
|
|
+ }
|
||
|
|
|
||
|
|
if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
|
||
|
|
const struct iphdr *iph = ip_hdr(skb);
|
||
|
|
--- a/net/ipv6/tcpv6_offload.c
|
||
|
|
+++ b/net/ipv6/tcpv6_offload.c
|
||
|
|
@@ -158,8 +158,14 @@ static struct sk_buff *tcp6_gso_segment(
|
||
|
|
if (!pskb_may_pull(skb, sizeof(*th)))
|
||
|
|
return ERR_PTR(-EINVAL);
|
||
|
|
|
||
|
|
- if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST)
|
||
|
|
- return __tcp6_gso_segment_list(skb, features);
|
||
|
|
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST) {
|
||
|
|
+ struct tcphdr *th = tcp_hdr(skb);
|
||
|
|
+
|
||
|
|
+ if (skb_pagelen(skb) - th->doff * 4 == skb_shinfo(skb)->gso_size)
|
||
|
|
+ return __tcp6_gso_segment_list(skb, features);
|
||
|
|
+
|
||
|
|
+ skb->ip_summed = CHECKSUM_NONE;
|
||
|
|
+ }
|
||
|
|
|
||
|
|
if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
|
||
|
|
const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
|