diff options
author | Kuniyuki Iwashima | 2022-07-22 11:22:00 -0700 |
---|---|---|
committer | David S. Miller | 2022-07-25 12:42:09 +0100 |
commit | 02739545951ad4c1215160db7fbf9b7a918d3c0b (patch) | |
tree | 996da2606ed68117cf50b75030cf649148b53f24 | |
parent | 59bf6c65a09fff74215517aecffbbdcd67df76e3 (diff) |
net: Fix data-races around sysctl_[rw]mem(_offset)?.
While reading these sysctl variables, they can be changed concurrently.
Thus, we need to add READ_ONCE() to their readers.
- .sysctl_rmem
- .sysctl_rwmem
- .sysctl_rmem_offset
- .sysctl_wmem_offset
- sysctl_tcp_rmem[1, 2]
- sysctl_tcp_wmem[1, 2]
- sysctl_decnet_rmem[1]
- sysctl_decnet_wmem[1]
- sysctl_tipc_rmem[1]
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | include/net/sock.h | 8 | ||||
-rw-r--r-- | net/decnet/af_decnet.c | 4 | ||||
-rw-r--r-- | net/ipv4/tcp.c | 6 | ||||
-rw-r--r-- | net/ipv4/tcp_input.c | 13 | ||||
-rw-r--r-- | net/ipv4/tcp_output.c | 2 | ||||
-rw-r--r-- | net/mptcp/protocol.c | 6 | ||||
-rw-r--r-- | net/tipc/socket.c | 2 |
7 files changed, 21 insertions, 20 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 9fa54762e077..7a48991cdb19 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2843,18 +2843,18 @@ static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) { /* Does this proto have per netns sysctl_wmem ? */ if (proto->sysctl_wmem_offset) - return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); + return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); - return *proto->sysctl_wmem; + return READ_ONCE(*proto->sysctl_wmem); } static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) { /* Does this proto have per netns sysctl_rmem ? */ if (proto->sysctl_rmem_offset) - return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); + return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); - return *proto->sysctl_rmem; + return READ_ONCE(*proto->sysctl_rmem); } /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c index dc92a67baea3..7d542eb46172 100644 --- a/net/decnet/af_decnet.c +++ b/net/decnet/af_decnet.c @@ -480,8 +480,8 @@ static struct sock *dn_alloc_sock(struct net *net, struct socket *sock, gfp_t gf sk->sk_family = PF_DECnet; sk->sk_protocol = 0; sk->sk_allocation = gfp; - sk->sk_sndbuf = sysctl_decnet_wmem[1]; - sk->sk_rcvbuf = sysctl_decnet_rmem[1]; + sk->sk_sndbuf = READ_ONCE(sysctl_decnet_wmem[1]); + sk->sk_rcvbuf = READ_ONCE(sysctl_decnet_rmem[1]); /* Initialization of DECnet Session Control Port */ scp = DN_SK(sk); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index a11e5de3a4c3..002a4a04efbe 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -452,8 +452,8 @@ void tcp_init_sock(struct sock *sk) icsk->icsk_sync_mss = tcp_sync_mss; - WRITE_ONCE(sk->sk_sndbuf, sock_net(sk)->ipv4.sysctl_tcp_wmem[1]); - WRITE_ONCE(sk->sk_rcvbuf, sock_net(sk)->ipv4.sysctl_tcp_rmem[1]); + WRITE_ONCE(sk->sk_sndbuf, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[1])); + WRITE_ONCE(sk->sk_rcvbuf, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[1])); sk_sockets_allocated_inc(sk); } @@ -1724,7 +1724,7 @@ int tcp_set_rcvlowat(struct sock *sk, int val) if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) cap = sk->sk_rcvbuf >> 1; else - cap = sock_net(sk)->ipv4.sysctl_tcp_rmem[2] >> 1; + cap = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1; val = min(val, cap); WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index dd05238f79f6..ff2e0d87aee4 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -426,7 +426,7 @@ static void tcp_sndbuf_expand(struct sock *sk) if (sk->sk_sndbuf < sndmem) WRITE_ONCE(sk->sk_sndbuf, - min(sndmem, sock_net(sk)->ipv4.sysctl_tcp_wmem[2])); + min(sndmem, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[2]))); } /* 2. Tuning advertised window (window_clamp, rcv_ssthresh) @@ -461,7 +461,7 @@ static int __tcp_grow_window(const struct sock *sk, const struct sk_buff *skb, struct tcp_sock *tp = tcp_sk(sk); /* Optimize this! */ int truesize = tcp_win_from_space(sk, skbtruesize) >> 1; - int window = tcp_win_from_space(sk, sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1; + int window = tcp_win_from_space(sk, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])) >> 1; while (tp->rcv_ssthresh <= window) { if (truesize <= skb->len) @@ -574,16 +574,17 @@ static void tcp_clamp_window(struct sock *sk) struct tcp_sock *tp = tcp_sk(sk); struct inet_connection_sock *icsk = inet_csk(sk); struct net *net = sock_net(sk); + int rmem2; icsk->icsk_ack.quick = 0; + rmem2 = READ_ONCE(net->ipv4.sysctl_tcp_rmem[2]); - if (sk->sk_rcvbuf < net->ipv4.sysctl_tcp_rmem[2] && + if (sk->sk_rcvbuf < rmem2 && !(sk->sk_userlocks & SOCK_RCVBUF_LOCK) && !tcp_under_memory_pressure(sk) && sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)) { WRITE_ONCE(sk->sk_rcvbuf, - min(atomic_read(&sk->sk_rmem_alloc), - net->ipv4.sysctl_tcp_rmem[2])); + min(atomic_read(&sk->sk_rmem_alloc), rmem2)); } if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) tp->rcv_ssthresh = min(tp->window_clamp, 2U * tp->advmss); @@ -745,7 +746,7 @@ void tcp_rcv_space_adjust(struct sock *sk) do_div(rcvwin, tp->advmss); rcvbuf = min_t(u64, rcvwin * rcvmem, - sock_net(sk)->ipv4.sysctl_tcp_rmem[2]); + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); if (rcvbuf > sk->sk_rcvbuf) { WRITE_ONCE(sk->sk_rcvbuf, rcvbuf); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 2efe41c84ee8..4c376b6d8764 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -238,7 +238,7 @@ void tcp_select_initial_window(const struct sock *sk, int __space, __u32 mss, *rcv_wscale = 0; if (wscale_ok) { /* Set window scaling on max possible window */ - space = max_t(u32, space, sock_net(sk)->ipv4.sysctl_tcp_rmem[2]); + space = max_t(u32, space, READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); space = max_t(u32, space, sysctl_rmem_max); space = min_t(u32, space, *window_clamp); *rcv_wscale = clamp_t(int, ilog2(space) - 15, diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 9bbd8cbe0acb..7e1518bb6115 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1926,7 +1926,7 @@ static void mptcp_rcv_space_adjust(struct mptcp_sock *msk, int copied) do_div(rcvwin, advmss); rcvbuf = min_t(u64, rcvwin * rcvmem, - sock_net(sk)->ipv4.sysctl_tcp_rmem[2]); + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2])); if (rcvbuf > sk->sk_rcvbuf) { u32 window_clamp; @@ -2669,8 +2669,8 @@ static int mptcp_init_sock(struct sock *sk) mptcp_ca_reset(sk); sk_sockets_allocated_inc(sk); - sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1]; - sk->sk_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[1]; + sk->sk_rcvbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[1]); + sk->sk_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[1]); return 0; } diff --git a/net/tipc/socket.c b/net/tipc/socket.c index 43509c7e90fc..f1c3b8eb4b3d 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -517,7 +517,7 @@ static int tipc_sk_create(struct net *net, struct socket *sock, timer_setup(&sk->sk_timer, tipc_sk_timeout, 0); sk->sk_shutdown = 0; sk->sk_backlog_rcv = tipc_sk_backlog_rcv; - sk->sk_rcvbuf = sysctl_tipc_rmem[1]; + sk->sk_rcvbuf = READ_ONCE(sysctl_tipc_rmem[1]); sk->sk_data_ready = tipc_data_ready; sk->sk_write_space = tipc_write_space; sk->sk_destruct = tipc_sock_destruct; |