diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-06-06 18:46:51 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-06-10 15:11:22 +0300 |
| commit | d37fe4255abe8e7b419b90c5847e8ec2b8debb08 (patch) | |
| tree | b673e099e58133c68a248c87d757e8a43958dd5b | |
| parent | 5add2f7288468f35a374620dabf126c13baaea9c (diff) | |
| download | linux-d37fe4255abe8e7b419b90c5847e8ec2b8debb08.tar.xz | |
tcp: fix race in tcp_v6_syn_recv_sock()
tcp_v6_syn_recv_sock() calls ip6_dst_store() before
inet_sk(newsk)->pinet6 has been set up.
This means ip6_dst_store() writes over the parent (listener)
np->dst_cookie.
This is racy because multiple threads could share the same
parent and their final np->dst_cookie could be wrong.
Move ip6_dst_store() call after inet_sk(newsk)->pinet6
has been changed and after the copy of parent ipv6_pinfo.
Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 8c577b651bfc..729faf8bd366 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1439,7 +1439,6 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * */ newsk->sk_gso_type = SKB_GSO_TCPV6; - ip6_dst_store(newsk, dst, NULL, NULL); inet6_sk_rx_dst_set(newsk, skb); inet_sk(newsk)->pinet6 = tcp_inet6_sk(newsk); @@ -1450,6 +1449,8 @@ static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff * memcpy(newnp, np, sizeof(struct ipv6_pinfo)); + ip6_dst_store(newsk, dst, NULL, NULL); + newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr; newnp->saddr = ireq->ir_v6_loc_addr; newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr; |