This is a note to let you know that I've just added the patch titled net: Introduce a new proto_ops ->read_skb() to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-introduce-a-new-proto_ops-read_skb.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2e55a8ad6cdcf880e5bae3a674eafefb0ac63458 Author: Cong Wang <cong.wang@xxxxxxxxxxxxx> Date: Wed Jun 15 09:20:12 2022 -0700 net: Introduce a new proto_ops ->read_skb() [ Upstream commit 965b57b469a589d64d81b1688b38dcb537011bb0 ] Currently both splice() and sockmap use ->read_sock() to read skb from receive queue, but for sockmap we only read one entire skb at a time, so ->read_sock() is too conservative to use. Introduce a new proto_ops ->read_skb() which supports this sematic, with this we can finally pass the ownership of skb to recv actors. For non-TCP protocols, all ->read_sock() can be simply converted to ->read_skb(). Signed-off-by: Cong Wang <cong.wang@xxxxxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Reviewed-by: John Fastabend <john.fastabend@xxxxxxxxx> Link: https://lore.kernel.org/bpf/20220615162014.89193-3-xiyou.wangcong@xxxxxxxxx Stable-dep-of: 6648e613226e ("bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/linux/net.h b/include/linux/net.h index ba736b457a068..3e000dadeb8f3 100644 --- a/include/linux/net.h +++ b/include/linux/net.h @@ -133,6 +133,8 @@ struct module; struct sk_buff; typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *, unsigned int, size_t); +typedef int (*skb_read_actor_t)(struct sock *, struct sk_buff *); + struct proto_ops { int family; @@ -195,6 +197,8 @@ struct proto_ops { */ int (*read_sock)(struct sock *sk, read_descriptor_t *desc, sk_read_actor_t recv_actor); + /* This is different from read_sock(), it reads an entire skb at a time. */ + int (*read_skb)(struct sock *sk, skb_read_actor_t recv_actor); int (*sendpage_locked)(struct sock *sk, struct page *page, int offset, size_t size, int flags); int (*sendmsg_locked)(struct sock *sk, struct msghdr *msg, diff --git a/include/net/tcp.h b/include/net/tcp.h index 3047a8b3dbd1c..bdc5a16af8190 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -663,8 +663,7 @@ void tcp_get_info(struct sock *, struct tcp_info *); /* Read 'sendfile()'-style from a TCP socket */ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, sk_read_actor_t recv_actor); -int tcp_read_skb(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor); +int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor); void tcp_initialize_rcv_mss(struct sock *sk); diff --git a/include/net/udp.h b/include/net/udp.h index 10508c66e7a19..20ae344bc1082 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -329,8 +329,7 @@ struct sock *__udp6_lib_lookup(struct net *net, struct sk_buff *skb); struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, __be16 sport, __be16 dport); -int udp_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor); +int udp_read_skb(struct sock *sk, skb_read_actor_t recv_actor); /* UDP uses skb->dev_scratch to cache as much information as possible and avoid * possibly multiple cache miss on dequeue() diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 9cd14212dcd0b..68418954ac492 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -1173,21 +1173,17 @@ static void sk_psock_done_strp(struct sk_psock *psock) } #endif /* CONFIG_BPF_STREAM_PARSER */ -static int sk_psock_verdict_recv(read_descriptor_t *desc, struct sk_buff *skb, - unsigned int offset, size_t orig_len) +static int sk_psock_verdict_recv(struct sock *sk, struct sk_buff *skb) { - struct sock *sk = (struct sock *)desc->arg.data; struct sk_psock *psock; struct bpf_prog *prog; int ret = __SK_DROP; - int len = orig_len; + int len = skb->len; /* clone here so sk_eat_skb() in tcp_read_sock does not drop our data */ skb = skb_clone(skb, GFP_ATOMIC); - if (!skb) { - desc->error = -ENOMEM; + if (!skb) return 0; - } rcu_read_lock(); psock = sk_psock(sk); @@ -1217,16 +1213,10 @@ static int sk_psock_verdict_recv(read_descriptor_t *desc, struct sk_buff *skb, static void sk_psock_verdict_data_ready(struct sock *sk) { struct socket *sock = sk->sk_socket; - read_descriptor_t desc; - if (unlikely(!sock || !sock->ops || !sock->ops->read_sock)) + if (unlikely(!sock || !sock->ops || !sock->ops->read_skb)) return; - - desc.arg.data = sk; - desc.error = 0; - desc.count = 1; - - sock->ops->read_sock(sk, &desc, sk_psock_verdict_recv); + sock->ops->read_skb(sk, sk_psock_verdict_recv); } void sk_psock_start_verdict(struct sock *sk, struct sk_psock *psock) diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 487f75993bf4f..f931d2534ab42 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1050,6 +1050,7 @@ const struct proto_ops inet_stream_ops = { .sendpage = inet_sendpage, .splice_read = tcp_splice_read, .read_sock = tcp_read_sock, + .read_skb = tcp_read_skb, .sendmsg_locked = tcp_sendmsg_locked, .sendpage_locked = tcp_sendpage_locked, .peek_len = tcp_peek_len, @@ -1077,7 +1078,7 @@ const struct proto_ops inet_dgram_ops = { .setsockopt = sock_common_setsockopt, .getsockopt = sock_common_getsockopt, .sendmsg = inet_sendmsg, - .read_sock = udp_read_sock, + .read_skb = udp_read_skb, .recvmsg = inet_recvmsg, .mmap = sock_no_mmap, .sendpage = inet_sendpage, diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 3647a5f08c22d..3fd4de1961a62 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1705,8 +1705,7 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, } EXPORT_SYMBOL(tcp_read_sock); -int tcp_read_skb(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor) +int tcp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { struct tcp_sock *tp = tcp_sk(sk); u32 seq = tp->copied_seq; @@ -1721,7 +1720,7 @@ int tcp_read_skb(struct sock *sk, read_descriptor_t *desc, int used; __skb_unlink(skb, &sk->sk_receive_queue); - used = recv_actor(desc, skb, 0, skb->len); + used = recv_actor(sk, skb); if (used <= 0) { if (!copied) copied = used; @@ -1736,9 +1735,7 @@ int tcp_read_skb(struct sock *sk, read_descriptor_t *desc, break; } consume_skb(skb); - if (!desc->count) - break; - WRITE_ONCE(tp->copied_seq, seq); + break; } WRITE_ONCE(tp->copied_seq, seq); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d0387e5eee5b5..6a054bfb17850 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1819,8 +1819,7 @@ struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags, } EXPORT_SYMBOL(__skb_recv_udp); -int udp_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor) +int udp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { int copied = 0; @@ -1842,7 +1841,7 @@ int udp_read_sock(struct sock *sk, read_descriptor_t *desc, continue; } - used = recv_actor(desc, skb, 0, skb->len); + used = recv_actor(sk, skb); if (used <= 0) { if (!copied) copied = used; @@ -1853,13 +1852,12 @@ int udp_read_sock(struct sock *sk, read_descriptor_t *desc, } kfree_skb(skb); - if (!desc->count) - break; + break; } return copied; } -EXPORT_SYMBOL(udp_read_sock); +EXPORT_SYMBOL(udp_read_skb); /* * This should be easy, if there is something there we diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 8e0c33b683010..1b7749882c7ab 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -707,6 +707,7 @@ const struct proto_ops inet6_stream_ops = { .sendpage_locked = tcp_sendpage_locked, .splice_read = tcp_splice_read, .read_sock = tcp_read_sock, + .read_skb = tcp_read_skb, .peek_len = tcp_peek_len, #ifdef CONFIG_COMPAT .compat_ioctl = inet6_compat_ioctl, @@ -732,7 +733,7 @@ const struct proto_ops inet6_dgram_ops = { .getsockopt = sock_common_getsockopt, /* ok */ .sendmsg = inet6_sendmsg, /* retpoline's sake */ .recvmsg = inet6_recvmsg, /* retpoline's sake */ - .read_sock = udp_read_sock, + .read_skb = udp_read_skb, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, .set_peek_off = sk_set_peek_off, diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index f66f867049015..bf610fad8775d 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -700,10 +700,8 @@ static ssize_t unix_stream_splice_read(struct socket *, loff_t *ppos, unsigned int flags); static int unix_dgram_sendmsg(struct socket *, struct msghdr *, size_t); static int unix_dgram_recvmsg(struct socket *, struct msghdr *, size_t, int); -static int unix_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor); -static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor); +static int unix_read_skb(struct sock *sk, skb_read_actor_t recv_actor); +static int unix_stream_read_skb(struct sock *sk, skb_read_actor_t recv_actor); static int unix_dgram_connect(struct socket *, struct sockaddr *, int, int); static int unix_seqpacket_sendmsg(struct socket *, struct msghdr *, size_t); @@ -757,7 +755,7 @@ static const struct proto_ops unix_stream_ops = { .shutdown = unix_shutdown, .sendmsg = unix_stream_sendmsg, .recvmsg = unix_stream_recvmsg, - .read_sock = unix_stream_read_sock, + .read_skb = unix_stream_read_skb, .mmap = sock_no_mmap, .sendpage = unix_stream_sendpage, .splice_read = unix_stream_splice_read, @@ -782,7 +780,7 @@ static const struct proto_ops unix_dgram_ops = { .listen = sock_no_listen, .shutdown = unix_shutdown, .sendmsg = unix_dgram_sendmsg, - .read_sock = unix_read_sock, + .read_skb = unix_read_skb, .recvmsg = unix_dgram_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, @@ -2412,8 +2410,7 @@ static int unix_dgram_recvmsg(struct socket *sock, struct msghdr *msg, size_t si return __unix_dgram_recvmsg(sk, msg, size, flags); } -static int unix_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor) +static int unix_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { int copied = 0; @@ -2428,7 +2425,7 @@ static int unix_read_sock(struct sock *sk, read_descriptor_t *desc, if (!skb) return err; - used = recv_actor(desc, skb, 0, skb->len); + used = recv_actor(sk, skb); if (used <= 0) { if (!copied) copied = used; @@ -2439,8 +2436,7 @@ static int unix_read_sock(struct sock *sk, read_descriptor_t *desc, } kfree_skb(skb); - if (!desc->count) - break; + break; } return copied; @@ -2580,13 +2576,12 @@ static struct sk_buff *manage_oob(struct sk_buff *skb, struct sock *sk, } #endif -static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc, - sk_read_actor_t recv_actor) +static int unix_stream_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { if (unlikely(sk->sk_state != TCP_ESTABLISHED)) return -ENOTCONN; - return unix_read_sock(sk, desc, recv_actor); + return unix_read_skb(sk, recv_actor); } static int unix_stream_read_generic(struct unix_stream_read_state *state,