git: 590b45036ee1 - main - socket: Handle the possibility of a protocol with no ctloutput

From: Mark Johnston <markj_at_FreeBSD.org>
Date: Mon, 31 Mar 2025 09:06:34 UTC
The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=590b45036ee16163f9eb8c34791d197e76de502d

commit 590b45036ee16163f9eb8c34791d197e76de502d
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-03-29 08:55:08 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-03-31 09:01:09 +0000

    socket: Handle the possibility of a protocol with no ctloutput
    
    Add a default ctloutput handler and remove various NULL checks.  This
    fixes a problem wherein the generic SO_SETFIB handler did not check
    whether the protocol has a ctloutput implementation before calling the
    function pointer.
    
    Reported by:    syzkaller
    Reviewed by:    glebius
    Fixes:          caccbaef8e26 ("socket: Move SO_SETFIB handling to protocol layers")
    MFC after:      1 week
    Differential Revision:  https://reviews.freebsd.org/D49436
---
 sys/kern/uipc_domain.c |  7 +++++++
 sys/kern/uipc_socket.c | 12 +++---------
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/sys/kern/uipc_domain.c b/sys/kern/uipc_domain.c
index 51e0f8cc7726..2d68e11b9f0a 100644
--- a/sys/kern/uipc_domain.c
+++ b/sys/kern/uipc_domain.c
@@ -97,6 +97,12 @@ pr_control_notsupp(struct socket *so, u_long cmd, void *data,
 	return (EOPNOTSUPP);
 }
 
+static int
+pr_ctloutput_notsupp(struct socket *so, struct sockopt *sopt)
+{
+	return (ENOPROTOOPT);
+}
+
 static int
 pr_disconnect_notsupp(struct socket *so)
 {
@@ -194,6 +200,7 @@ pr_init(struct domain *dom, struct protosw *pr)
 	NOTSUPP(pr_connect2);
 	NOTSUPP(pr_connectat);
 	NOTSUPP(pr_control);
+	NOTSUPP(pr_ctloutput);
 	NOTSUPP(pr_disconnect);
 	NOTSUPP(pr_listen);
 	NOTSUPP(pr_peeraddr);
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 63d30f04c8e0..ac00696236a5 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -3804,10 +3804,7 @@ sosetopt(struct socket *so, struct sockopt *sopt)
 	CURVNET_SET(so->so_vnet);
 	error = 0;
 	if (sopt->sopt_level != SOL_SOCKET) {
-		if (so->so_proto->pr_ctloutput != NULL)
-			error = (*so->so_proto->pr_ctloutput)(so, sopt);
-		else
-			error = ENOPROTOOPT;
+		error = (*so->so_proto->pr_ctloutput)(so, sopt);
 	} else {
 		switch (sopt->sopt_name) {
 		case SO_ACCEPTFILTER:
@@ -4017,7 +4014,7 @@ sosetopt(struct socket *so, struct sockopt *sopt)
 				error = ENOPROTOOPT;
 			break;
 		}
-		if (error == 0 && so->so_proto->pr_ctloutput != NULL)
+		if (error == 0)
 			(void)(*so->so_proto->pr_ctloutput)(so, sopt);
 	}
 bad:
@@ -4068,10 +4065,7 @@ sogetopt(struct socket *so, struct sockopt *sopt)
 	CURVNET_SET(so->so_vnet);
 	error = 0;
 	if (sopt->sopt_level != SOL_SOCKET) {
-		if (so->so_proto->pr_ctloutput != NULL)
-			error = (*so->so_proto->pr_ctloutput)(so, sopt);
-		else
-			error = ENOPROTOOPT;
+		error = (*so->so_proto->pr_ctloutput)(so, sopt);
 		CURVNET_RESTORE();
 		return (error);
 	} else {