Commit 9201f60a authored Oct 28, 2022 by Jakub Kicinski

Merge branch 'a-few-corrections-for-sock_support_zc'

Pavel Begunkov says:

====================
a few corrections for SOCK_SUPPORT_ZC

There are several places/cases that got overlooked in regards to
SOCK_SUPPORT_ZC. We're lacking the flag for IPv6 UDP sockets and
accepted TCP sockets. We also should clear the flag when someone
tries to hijack a socket by replacing the ->sk_prot callbacks.
====================

Link: https://lore.kernel.org/r/cover.1666825799.git.asml.silence@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parents 1208b93d 71b7786e

include/net/sock.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -1889,6 +1889,13 @@ void sock_kfree_s(struct sock sk, void mem, int size);
		void sock_kzfree_s(struct sock sk, void mem, int size);
		void sk_send_sigurg(struct sock *sk);

		static inline void sock_replace_proto(struct sock sk, struct proto proto)
		{
		if (sk->sk_socket)
		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
		WRITE_ONCE(sk->sk_prot, proto);
		}

		struct sockcm_cookie {
		u64 transmit_time;
		u32 mark;

net/ipv4/af_inet.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -754,6 +754,8 @@ int inet_accept(struct socket sock, struct socket newsock, int flags,
		(TCPF_ESTABLISHED \| TCPF_SYN_RECV \|
		TCPF_CLOSE_WAIT \| TCPF_CLOSE)));

		if (test_bit(SOCK_SUPPORT_ZC, &sock->flags))
		set_bit(SOCK_SUPPORT_ZC, &newsock->flags);
		sock_graft(sk2, newsock);

		newsock->state = SS_CONNECTED;

net/ipv4/tcp_bpf.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -607,7 +607,7 @@ int tcp_bpf_update_proto(struct sock sk, struct sk_psock psock, bool restore)
		} else {
		sk->sk_write_space = psock->saved_write_space;
		/* Pairs with lockless read in sk_clone_lock() */
		WRITE_ONCE(sk->sk_prot, psock->sk_proto);
		sock_replace_proto(sk, psock->sk_proto);
		}
		return 0;
		}
		@@ -620,7 +620,7 @@ int tcp_bpf_update_proto(struct sock sk, struct sk_psock psock, bool restore)
		}

		/* Pairs with lockless read in sk_clone_lock() */
		WRITE_ONCE(sk->sk_prot, &tcp_bpf_prots[family][config]);
		sock_replace_proto(sk, &tcp_bpf_prots[family][config]);
		return 0;
		}
		EXPORT_SYMBOL_GPL(tcp_bpf_update_proto);

net/ipv4/tcp_ulp.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -136,6 +136,9 @@ static int __tcp_set_ulp(struct sock sk, const struct tcp_ulp_ops ulp_ops)
		if (icsk->icsk_ulp_ops)
		goto out_err;

		if (sk->sk_socket)
		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);

		err = ulp_ops->init(sk);
		if (err)
		goto out_err;

net/ipv4/udp_bpf.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -141,14 +141,14 @@ int udp_bpf_update_proto(struct sock sk, struct sk_psock psock, bool restore)

		if (restore) {
		sk->sk_write_space = psock->saved_write_space;
		WRITE_ONCE(sk->sk_prot, psock->sk_proto);
		sock_replace_proto(sk, psock->sk_proto);
		return 0;
		}

		if (sk->sk_family == AF_INET6)
		udp_bpf_check_v6_needs_rebuild(psock->sk_proto);

		WRITE_ONCE(sk->sk_prot, &udp_bpf_prots[family]);
		sock_replace_proto(sk, &udp_bpf_prots[family]);
		return 0;
		}
		EXPORT_SYMBOL_GPL(udp_bpf_update_proto);