From e8f6e5b2d969fdf7e8f0a9a0a87eede357618fe9 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Wed, 3 May 2023 11:56:46 -0400 Subject: [PATCH] unix: Fix locking in uipc_peeraddr() After the locking protocol changed in commit 75a67bf3d00d ("AF_UNIX: make unix socket locking finer grained"), uipc_peeraddr() was not updated accordingly. The link lock now only protects global socket lists. The PCB lock is used to protect the link between connected PCBs, so use that. Remove an old comment which appears to be noting that unp_conn is not set for connected SOCK_DGRAM sockets (in one direction anyway). Reviewed by: glebius MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D39855 --- sys/kern/uipc_usrreq.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/sys/kern/uipc_usrreq.c b/sys/kern/uipc_usrreq.c index 294ef807416..bd7a2cca245 100644 --- a/sys/kern/uipc_usrreq.c +++ b/sys/kern/uipc_usrreq.c @@ -885,15 +885,10 @@ uipc_peeraddr(struct socket *so, struct sockaddr **nam) KASSERT(unp != NULL, ("uipc_peeraddr: unp == NULL")); *nam = malloc(sizeof(struct sockaddr_un), M_SONAME, M_WAITOK); - UNP_LINK_RLOCK(); - /* - * XXX: It seems that this test always fails even when connection is - * established. So, this else clause is added as workaround to - * return PF_LOCAL sockaddr. - */ - unp2 = unp->unp_conn; + + UNP_PCB_LOCK(unp); + unp2 = unp_pcb_lock_peer(unp); if (unp2 != NULL) { - UNP_PCB_LOCK(unp2); if (unp2->unp_addr != NULL) sa = (struct sockaddr *) unp2->unp_addr; else @@ -904,7 +899,7 @@ uipc_peeraddr(struct socket *so, struct sockaddr **nam) sa = &sun_noname; bcopy(sa, *nam, sa->sa_len); } - UNP_LINK_RUNLOCK(); + UNP_PCB_UNLOCK(unp); return (0); }