diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-11 17:15:32 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-21 21:09:29 +0200 |
| commit | a720ca682386beec7829d1af60cd0f21c6597a01 (patch) | |
| tree | 3275dc9e9e6cb8fb0ebac8dc647d820eb65d72f0 | |
| parent | d93993b165243a0f614b946f417fbbb137b34ee2 (diff) | |
ipv4: Fix data-races around sysctl_ip_dynaddr.
[ Upstream commit e49e4aff7ec19b2d0d0957ee30e93dade57dab9e ]
While reading sysctl_ip_dynaddr, 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>
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 2 | ||||
| -rw-r--r-- | net/ipv4/af_inet.c | 4 |
2 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index ae56957f51e4..e315e6052b9f 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -887,7 +887,7 @@ ip_nonlocal_bind - BOOLEAN which can be quite useful - but may break some applications. Default: 0 -ip_dynaddr - BOOLEAN +ip_dynaddr - INTEGER If set non-zero, enables support for dynamic addresses. If set to a non-zero value larger than 1, a kernel log message will be printed when dynamic address rewriting diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index d8c22246629a..dadd42a07c07 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1209,7 +1209,7 @@ static int inet_sk_reselect_saddr(struct sock *sk) if (new_saddr == old_saddr) return 0; - if (sock_net(sk)->ipv4.sysctl_ip_dynaddr > 1) { + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) > 1) { pr_info("%s(): shifting inet->saddr from %pI4 to %pI4\n", __func__, &old_saddr, &new_saddr); } @@ -1264,7 +1264,7 @@ int inet_sk_rebuild_header(struct sock *sk) * Other protocols have to map its equivalent state to TCP_SYN_SENT. * DCCP maps its DCCP_REQUESTING state to TCP_SYN_SENT. -acme */ - if (!sock_net(sk)->ipv4.sysctl_ip_dynaddr || + if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_dynaddr) || sk->sk_state != TCP_SYN_SENT || (sk->sk_userlocks & SOCK_BINDADDR_LOCK) || (err = inet_sk_reselect_saddr(sk)) != 0) |