summaryrefslogtreecommitdiffstats
path: root/net/ipv4
diff options
context:
space:
mode:
authorKuniyuki Iwashima <kuniyu@amazon.com>2022-07-15 19:17:50 +0200
committerDavid S. Miller <davem@davemloft.net>2022-07-18 13:21:54 +0200
commit39e24435a776e9de5c6dd188836cf2523547804b (patch)
treece395ff289b73323451466c54d20b0c8bf4668f0 /net/ipv4
parenttcp: Fix data-races around sysctl_tcp_reordering. (diff)
downloadlinux-39e24435a776e9de5c6dd188836cf2523547804b.tar.xz
linux-39e24435a776e9de5c6dd188836cf2523547804b.zip
tcp: Fix data-races around some timeout sysctl knobs.
While reading these sysctl knobs, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. - tcp_retries1 - tcp_retries2 - tcp_orphan_retries - tcp_fin_timeout Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
-rw-r--r--net/ipv4/tcp.c2
-rw-r--r--net/ipv4/tcp_output.c2
-rw-r--r--net/ipv4/tcp_timer.c10
3 files changed, 7 insertions, 7 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b3632fa5df07..b1b1bcbc4f60 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3973,7 +3973,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
case TCP_LINGER2:
val = tp->linger2;
if (val >= 0)
- val = (val ? : net->ipv4.sysctl_tcp_fin_timeout) / HZ;
+ val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ;
break;
case TCP_DEFER_ACCEPT:
val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept,
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 02ab3a9c6657..3b3552d292a5 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -4090,7 +4090,7 @@ void tcp_send_probe0(struct sock *sk)
icsk->icsk_probes_out++;
if (err <= 0) {
- if (icsk->icsk_backoff < net->ipv4.sysctl_tcp_retries2)
+ if (icsk->icsk_backoff < READ_ONCE(net->ipv4.sysctl_tcp_retries2))
icsk->icsk_backoff++;
timeout = tcp_probe0_when(sk, TCP_RTO_MAX);
} else {
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index a234704e8163..ec5277becc6a 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -143,7 +143,7 @@ static int tcp_out_of_resources(struct sock *sk, bool do_reset)
*/
static int tcp_orphan_retries(struct sock *sk, bool alive)
{
- int retries = sock_net(sk)->ipv4.sysctl_tcp_orphan_retries; /* May be zero. */
+ int retries = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_orphan_retries); /* May be zero. */
/* We know from an ICMP that something is wrong. */
if (sk->sk_err_soft && !alive)
@@ -243,14 +243,14 @@ static int tcp_write_timeout(struct sock *sk)
READ_ONCE(net->ipv4.sysctl_tcp_syn_retries);
expired = icsk->icsk_retransmits >= retry_until;
} else {
- if (retransmits_timed_out(sk, net->ipv4.sysctl_tcp_retries1, 0)) {
+ if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1), 0)) {
/* Black hole detection */
tcp_mtu_probing(icsk, sk);
__dst_negative_advice(sk);
}
- retry_until = net->ipv4.sysctl_tcp_retries2;
+ retry_until = READ_ONCE(net->ipv4.sysctl_tcp_retries2);
if (sock_flag(sk, SOCK_DEAD)) {
const bool alive = icsk->icsk_rto < TCP_RTO_MAX;
@@ -381,7 +381,7 @@ static void tcp_probe_timer(struct sock *sk)
msecs_to_jiffies(icsk->icsk_user_timeout))
goto abort;
- max_probes = sock_net(sk)->ipv4.sysctl_tcp_retries2;
+ max_probes = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_retries2);
if (sock_flag(sk, SOCK_DEAD)) {
const bool alive = inet_csk_rto_backoff(icsk, TCP_RTO_MAX) < TCP_RTO_MAX;
@@ -589,7 +589,7 @@ out_reset_timer:
}
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
tcp_clamp_rto_to_user_timeout(sk), TCP_RTO_MAX);
- if (retransmits_timed_out(sk, net->ipv4.sysctl_tcp_retries1 + 1, 0))
+ if (retransmits_timed_out(sk, READ_ONCE(net->ipv4.sysctl_tcp_retries1) + 1, 0))
__sk_dst_reset(sk);
out:;