Re: [PATCH bpf-next v1 1/5] af_unix: add read_sock for stream socket types
From: Jakub Sitnicki <jakub@cloudflare.com>
Date: 2021-07-29 08:37:45
Also in:
bpf, linux-kselftest, lkml
On Tue, Jul 27, 2021 at 02:12 AM CEST, Jiang Wang wrote:
quoted hunk ↗ jump to hunk
To support sockmap for af_unix stream type, implement read_sock, which is similar to the read_sock for unix dgram sockets. Signed-off-by: Jiang Wang <redacted> Reviewed-by: Cong Wang <redacted>. --- net/unix/af_unix.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 89927678c..32eeb4a6a 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c@@ -672,6 +672,8 @@ 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_dgram_connect(struct socket *, struct sockaddr *, int, int); static int unix_seqpacket_sendmsg(struct socket *, struct msghdr *, size_t);@@ -725,6 +727,7 @@ 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, .mmap = sock_no_mmap, .sendpage = unix_stream_sendpage, .splice_read = unix_stream_splice_read,@@ -2311,6 +2314,15 @@ struct unix_stream_read_state { unsigned int splice_flags; }; +static int unix_stream_read_sock(struct sock *sk, read_descriptor_t *desc, + sk_read_actor_t recv_actor) +{ + if (unlikely(sk->sk_state != TCP_ESTABLISHED)) + return -EINVAL;
tcp_read_sock returns -ENOTCONN if socket is not connected. For the sake of being consistent, and in case we start propagating the error up the call chain, I'd use the same error code.
+
+ return unix_read_sock(sk, desc, recv_actor);
+}
+
static int unix_stream_read_generic(struct unix_stream_read_state *state,
bool freezable)
{