net: make sk->sk_rcvtimeo lockless

Followup of commit 285975dd6742 ("net: annotate data-races around
sk->sk_{rcv|snd}timeo").

Remove lock_sock()/release_sock() from ksmbd_tcp_rcv_timeout()
and add READ_ONCE()/WRITE_ONCE() where it is needed.

Also SO_RCVTIMEO_OLD and SO_RCVTIMEO_NEW can call sock_set_timeout()
without holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250620155536.335520-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/fs/smb/server/transport_tcp.c b/fs/smb/server/transport_tcp.c
index 4e9f98db9ff4098425ba315717f5fd1c6aae7579..f8c772a7cb439dd64ce7d294c8e431c925b78ab4 100644 (file)
--- a/fs/smb/server/transport_tcp.c
+++ b/fs/smb/server/transport_tcp.c
@@ -58,12 +58,10 @@ static inline void ksmbd_tcp_reuseaddr(struct socket *sock)
 
 static inline void ksmbd_tcp_rcv_timeout(struct socket *sock, s64 secs)
 {
-       lock_sock(sock->sk);
        if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
-               sock->sk->sk_rcvtimeo = secs * HZ;
+               WRITE_ONCE(sock->sk->sk_rcvtimeo, secs * HZ);
        else
-               sock->sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
-       release_sock(sock->sk);
+               WRITE_ONCE(sock->sk->sk_rcvtimeo, MAX_SCHEDULE_TIMEOUT);
 }
 
 static inline void ksmbd_tcp_snd_timeout(struct socket *sock, s64 secs)

diff --git a/include/net/sock.h b/include/net/sock.h
index b08e36bf96694235e54eec90a7abf8fcee6a55c6..0f2443d4ec581639eb3bdc46cb9b2932123e9246 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2596,7 +2596,7 @@ static inline gfp_t gfp_memcg_charge(void)
 
 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
 {
-       return noblock ? 0 : sk->sk_rcvtimeo;
+       return noblock ? 0 : READ_ONCE(sk->sk_rcvtimeo);
 }
 
 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)

diff --git a/net/core/sock.c b/net/core/sock.c
index b0b5a0a76045568d520e2bae2a1d489c5399a053..3a71d6c4ccf05831ede9861459e5ab9f793217eb 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1289,6 +1289,10 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
        case SO_SNDTIMEO_NEW:
                return sock_set_timeout(&sk->sk_sndtimeo, optval,
                                        optlen, optname == SO_SNDTIMEO_OLD);
+       case SO_RCVTIMEO_OLD:
+       case SO_RCVTIMEO_NEW:
+               return sock_set_timeout(&sk->sk_rcvtimeo, optval,
+                                       optlen, optname == SO_RCVTIMEO_OLD);
        }
 
        sockopt_lock_sock(sk);
@@ -1444,12 +1448,6 @@ set_sndbuf:
                        WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
                break;
                }
-       case SO_RCVTIMEO_OLD:
-       case SO_RCVTIMEO_NEW:
-               ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
-                                      optlen, optname == SO_RCVTIMEO_OLD);
-               break;
-
        case SO_ATTACH_FILTER: {
                struct sock_fprog fprog;
 

diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index cc77ec5769d82829cfb7a92096af8b79088df4f2..5958a80fe14cf3dea8a88d588ecfde121a9e66a5 100644 (file)
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -210,7 +210,7 @@ static int llc_ui_release(struct socket *sock)
        dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
                llc->laddr.lsap, llc->daddr.lsap);
        if (!llc_send_disc(sk))
-               llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
+               llc_ui_wait_for_disc(sk, READ_ONCE(sk->sk_rcvtimeo));
        if (!sock_flag(sk, SOCK_ZAPPED)) {
                struct llc_sap *sap = llc->sap;
 
@@ -455,7 +455,7 @@ static int llc_ui_shutdown(struct socket *sock, int how)
                goto out;
        rc = llc_send_disc(sk);
        if (!rc)
-               rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
+               rc = llc_ui_wait_for_disc(sk, READ_ONCE(sk->sk_rcvtimeo));
        /* Wake up anyone sleeping in poll */
        sk->sk_state_change(sk);
 out:
@@ -712,7 +712,7 @@ static int llc_ui_accept(struct socket *sock, struct socket *newsock,
                goto out;
        /* wait for a connection to arrive. */
        if (skb_queue_empty(&sk->sk_receive_queue)) {
-               rc = llc_wait_data(sk, sk->sk_rcvtimeo);
+               rc = llc_wait_data(sk, READ_ONCE(sk->sk_rcvtimeo));
                if (rc)
                        goto out;
        }

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 5b690a4d29692e487605fb9217d55e9cac66652b..4921416434f9a37ddce9a18efca0a4c23ba4967f 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -9492,7 +9492,7 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
        newsk->sk_sndbuf = sk->sk_sndbuf;
        newsk->sk_rcvbuf = sk->sk_rcvbuf;
        newsk->sk_lingertime = sk->sk_lingertime;
-       newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
+       newsk->sk_rcvtimeo = READ_ONCE(sk->sk_rcvtimeo);
        newsk->sk_sndtimeo = READ_ONCE(sk->sk_sndtimeo);
        newsk->sk_rxhash = sk->sk_rxhash;
 

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index 6375a86fe2b5f4e9c5aa9f2a71650e5708692be7..8d56e4db63e041724f156aa3ab30bab745a15bad 100644 (file)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -487,7 +487,7 @@ static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk,
        /* options we don't get control via setsockopt for */
        nsk->sk_type = osk->sk_type;
        nsk->sk_sndtimeo = READ_ONCE(osk->sk_sndtimeo);
-       nsk->sk_rcvtimeo = osk->sk_rcvtimeo;
+       nsk->sk_rcvtimeo = READ_ONCE(osk->sk_rcvtimeo);
        nsk->sk_mark = READ_ONCE(osk->sk_mark);
        nsk->sk_priority = READ_ONCE(osk->sk_priority);
        nsk->sk_rcvlowat = osk->sk_rcvlowat;

diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 521f5df80e10ca41ab187d7bd9c2461360ea2c49..5a4db151fe9578d25bbba7f65d2862ede1c4506e 100644 (file)
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -688,7 +688,7 @@ out:
 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
                     u8 expected_type, unsigned long timeout)
 {
-       long rcvtimeo = smc->clcsock->sk->sk_rcvtimeo;
+       long rcvtimeo = READ_ONCE(smc->clcsock->sk->sk_rcvtimeo);
        struct sock *clc_sk = smc->clcsock->sk;
        struct smc_clc_msg_hdr *clcm = buf;
        struct msghdr msg = {NULL, 0};
@@ -707,7 +707,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
         * sizeof(struct smc_clc_msg_hdr)
         */
        krflags = MSG_PEEK | MSG_WAITALL;
-       clc_sk->sk_rcvtimeo = timeout;
+       WRITE_ONCE(clc_sk->sk_rcvtimeo, timeout);
        iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1,
                        sizeof(struct smc_clc_msg_hdr));
        len = sock_recvmsg(smc->clcsock, &msg, krflags);
@@ -795,7 +795,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
        }
 
 out:
-       clc_sk->sk_rcvtimeo = rcvtimeo;
+       WRITE_ONCE(clc_sk->sk_rcvtimeo, rcvtimeo);
        return reason_code;
 }
 

diff --git a/net/strparser/strparser.c b/net/strparser/strparser.c
index d946bfb424c7f56f88dd6d074e902b6f24f9129f..43b1f558b33dbd02130a8ed975e7805f519430cf 100644 (file)
--- a/net/strparser/strparser.c
+++ b/net/strparser/strparser.c
@@ -333,7 +333,7 @@ static int strp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb,
        struct strparser *strp = (struct strparser *)desc->arg.data;
 
        return __strp_recv(desc, orig_skb, orig_offset, orig_len,
-                          strp->sk->sk_rcvbuf, strp->sk->sk_rcvtimeo);
+                          strp->sk->sk_rcvbuf, READ_ONCE(strp->sk->sk_rcvtimeo));
 }
 
 static int default_read_sock_done(struct strparser *strp, int err)

diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index 1f8ae9f4a3f1960d63557f34a3c9e8bbf55e8633..655d1e0ae25f7cc1c6d472ec543baad1c6a95c55 100644 (file)
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -891,7 +891,7 @@ static int x25_accept(struct socket *sock, struct socket *newsock,
        if (sk->sk_state != TCP_LISTEN)
                goto out2;
 
-       rc = x25_wait_for_data(sk, sk->sk_rcvtimeo);
+       rc = x25_wait_for_data(sk, READ_ONCE(sk->sk_rcvtimeo));
        if (rc)
                goto out2;
        skb = skb_dequeue(&sk->sk_receive_queue);