diff options
author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-20 09:50:21 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-03 12:03:46 +0200 |
commit | ff2932ac8ee1ce6f66ba1b5017843c87492cd1a8 (patch) | |
tree | 0241fd11a49603d51335b853d452b86883bf891c | |
parent | a88de75673e4f898564f90feb61e5d625e03c4c4 (diff) |
tcp: Fix a data-race around sysctl_tcp_challenge_ack_limit.
commit db3815a2fa691da145cfbe834584f31ad75df9ff upstream.
While reading sysctl_tcp_challenge_ack_limit, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its reader.
Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | net/ipv4/tcp_input.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 426f8fe02850..a5357ebfbcc0 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3622,7 +3622,7 @@ static void tcp_send_challenge_ack(struct sock *sk, const struct sk_buff *skb) /* Then check host-wide RFC 5961 rate limit. */ now = jiffies / HZ; if (now != challenge_timestamp) { - u32 ack_limit = net->ipv4.sysctl_tcp_challenge_ack_limit; + u32 ack_limit = READ_ONCE(net->ipv4.sysctl_tcp_challenge_ack_limit); u32 half = (ack_limit + 1) >> 1; challenge_timestamp = now; |