diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-15 20:17:47 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-29 18:19:16 +0300 |
| commit | dc1a78a2b274bad6b1be1561759ab670640af2d7 (patch) | |
| tree | fd2468130e9cded83c2b5c22f242cca85e2e0c88 /net/ipv6 | |
| parent | fc489055e7e8abe409224ff18863999cede92fbf (diff) | |
| download | linux-dc1a78a2b274bad6b1be1561759ab670640af2d7.tar.xz | |
tcp: Fix data-races around sysctl_tcp_syncookies.
[ Upstream commit f2e383b5bb6bbc60a0b94b87b3e49a2b1aefd11e ]
While reading sysctl_tcp_syncookies, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/syncookies.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index ca92dd6981de..12ae817aaf2e 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -141,7 +141,8 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) __u8 rcv_wscale; u32 tsoff = 0; - if (!sock_net(sk)->ipv4.sysctl_tcp_syncookies || !th->ack || th->rst) + if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies) || + !th->ack || th->rst) goto out; if (tcp_synq_no_recent_overflow(sk)) |