[net-next v5 1/4] net: af_unix: enable custom setsockopt for all socket types
From: Jori Koolstra <jkoolstra@xs4all.nl>
Date: 2026-07-12 19:29:15
Also in:
linux-fsdevel, lkml
Subsystem:
networking [general], networking [unix sockets], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Linus Torvalds
unix_setsockopt() and the SOCK_CUSTOM_SOCKOPT flag were only wired up for SOCK_STREAM (introduced along with the stream-only SO_INQ). Consequently custom AF_UNIX options are unreachable on SOCK_DGRAM and SOCK_SEQPACKET: those setsockopt() calls bypass unix_setsockopt() and fall through to the generic sock_setsockopt(), failing with -ENOPROTOOPT. Set SOCK_CUSTOM_SOCKOPT for every AF_UNIX socket type in unix_create(), and also for accepted sockets in unix_accept() (reachable for stream and seqpacket). This is a prerequisite for making SO_RIGHTS_NOTRUNC settable on all AF_UNIX socket types. Signed-off-by: Jori Koolstra <jkoolstra@xs4all.nl> --- net/unix/af_unix.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index f7a9d55eee8a..3d256255085b 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c@@ -949,7 +949,7 @@ static int unix_setsockopt(struct socket *sock, int level, int optname, switch (optname) { case SO_INQ: if (sk->sk_type != SOCK_STREAM) - return -EINVAL; + return -ENOPROTOOPT; if (val > 1 || val < 0) return -EINVAL;
@@ -1005,6 +1005,7 @@ static const struct proto_ops unix_dgram_ops = { #endif .listen = sock_no_listen, .shutdown = unix_shutdown, + .setsockopt = unix_setsockopt, .sendmsg = unix_dgram_sendmsg, .read_skb = unix_read_skb, .recvmsg = unix_dgram_recvmsg,
@@ -1029,6 +1030,7 @@ static const struct proto_ops unix_seqpacket_ops = { #endif .listen = unix_listen, .shutdown = unix_shutdown, + .setsockopt = unix_setsockopt, .sendmsg = unix_seqpacket_sendmsg, .recvmsg = unix_seqpacket_recvmsg, .mmap = sock_no_mmap,
@@ -1142,9 +1144,10 @@ static int unix_create(struct net *net, struct socket *sock, int protocol, if (protocol && protocol != PF_UNIX) return -EPROTONOSUPPORT; + set_bit(SOCK_CUSTOM_SOCKOPT, &sock->flags); + switch (sock->type) { case SOCK_STREAM: - set_bit(SOCK_CUSTOM_SOCKOPT, &sock->flags); sock->ops = &unix_stream_ops; break; /*
@@ -1864,8 +1867,7 @@ static int unix_accept(struct socket *sock, struct socket *newsock, skb_free_datagram(sk, skb); wake_up_interruptible(&unix_sk(sk)->peer_wait); - if (tsk->sk_type == SOCK_STREAM) - set_bit(SOCK_CUSTOM_SOCKOPT, &newsock->flags); + set_bit(SOCK_CUSTOM_SOCKOPT, &newsock->flags); /* attach accepted sock to socket */ unix_state_lock(tsk);
--
2.55.0