diff --git a/lib/libc/sys/bind.2 b/lib/libc/sys/bind.2
--- a/lib/libc/sys/bind.2
+++ b/lib/libc/sys/bind.2
@@ -128,6 +128,17 @@
 The name would reside on a read-only file system.
 .It Bq Er EISDIR
 An empty pathname was specified.
+.It Bq Er EEXIST
+The specified address (socket path) exists as a socket file but isn't linked
+to an alive socket (which means it is a stale socket file). This error code
+is non-POSIX and disabled by default. Traditional behaviour is to return
+.Er EADDRNOTAVAIL here. See
+.Xr unix 4 .
+.It Bq Er EFTYPE
+The specified address (socket path) exists as a non-socket file. This error
+code is non-POSIX and disabled by default. Traditional behaviour is to return
+.Er EADDRNOTAVAIL here. See
+.Xr unix 4 .
 .El
 .Sh SEE ALSO
 .Xr connect 2 ,
diff --git a/share/man/man4/unix.4 b/share/man/man4/unix.4
--- a/share/man/man4/unix.4
+++ b/share/man/man4/unix.4
@@ -119,6 +119,22 @@
 or
 .Xr sendto 2
 must be writable.
+.Pp
+The stale socket file which was not removed after socket close will cause
+the next
+.Xr bind 2
+call with this path to fail. The traditional behaviour is to set
+.Va errno
+to
+.Er EADDRNOTAVAIL
+when the specified path already exists, regardless of what exactly exists at
+the specified path. However, when
+.Va net.local.bind_exist_errext
+set to non-zero, the error code will be more detailed:
+.Er EADDRNOTAVAIL when the existing socket file actually bound to an existing
+socket,
+.Er EEXIST when the existing socket file is stale and
+.Er EFTYPE when the existing file is not a socket at all.
 .Sh CONTROL MESSAGES
 The
 .Ux Ns -domain
diff --git a/sys/kern/uipc_usrreq.c b/sys/kern/uipc_usrreq.c
--- a/sys/kern/uipc_usrreq.c
+++ b/sys/kern/uipc_usrreq.c
@@ -158,6 +158,7 @@
 static u_long	unpdg_recvspace = 16*1024;	/* support 8KB syslog msgs */
 static u_long	unpsp_sendspace = PIPSIZ;	/* really max datagram size */
 static u_long	unpsp_recvspace = PIPSIZ;
+static int	bind_exist_errext = 0;
 
 static SYSCTL_NODE(_net, PF_LOCAL, local, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
     "Local domain");
@@ -183,6 +184,9 @@
 	   &unpsp_sendspace, 0, "Default seqpacket send space.");
 SYSCTL_ULONG(_net_local_seqpacket, OID_AUTO, recvspace, CTLFLAG_RW,
 	   &unpsp_recvspace, 0, "Default seqpacket receive space.");
+SYSCTL_INT(_net_local, OID_AUTO, bind_exist_errext, CTLFLAG_RW,
+    &bind_exist_errext, 0,
+    "bind() will report EEXIST/EFTYPE for non-bound-socket existing files.");
 SYSCTL_INT(_net_local, OID_AUTO, inflight, CTLFLAG_RD, &unp_rights, 0,
     "File descriptors in flight.");
 SYSCTL_INT(_net_local, OID_AUTO, deferred, CTLFLAG_RD,
@@ -607,8 +611,19 @@
 		else
 			vput(nd.ni_dvp);
 		if (vp != NULL) {
+			if (bind_exist_errext == 0)
+				error = EADDRINUSE;
+			else if (vp->v_type != VSOCK)
+				error = EFTYPE;
+			else {
+				vn_lock(vp, LK_SHARED);
+				if (vp->v_unpcb == NULL)
+					error = EEXIST;
+				else
+					error = EADDRINUSE;
+				VOP_UNLOCK(vp, 0);
+			}
 			vrele(vp);
-			error = EADDRINUSE;
 			goto error;
 		}
 		error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH);