Unlock KERN_MAXPROC and KERN_MAXTHREAD from `kern_vars'. Both

`maxprocess' and `maxthread' are atomically accessed integers.

ok mpi

3 files changed, 14 insertions, 9 deletions

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index d0d465babb6..2f97fabaf89 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_fork.c,v 1.263 2024/08/16 16:19:03 mpi Exp $	*/
+/*	$OpenBSD: kern_fork.c,v 1.264 2024/08/20 07:48:23 mvs Exp $	*/
 /*	$NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 christos Exp $	*/
 
 /*
@@ -307,7 +307,7 @@ struct timeval fork_tfmrate = { 10, 0 };
 int
 fork_check_maxthread(uid_t uid)
 {
-	int val;
+	int maxthread_local, val;
 
 	/*
 	 * Although process entries are dynamically created, we still keep
@@ -318,8 +318,10 @@ fork_check_maxthread(uid_t uid)
 	 * the variable nthreads is the current number of procs, maxthread is
 	 * the limit.
 	 */
+	maxthread_local = atomic_load_int(&maxthread);
 	val = atomic_inc_int_nv(&nthreads);
-	if ((val > maxthread - 5 && uid != 0) || val > maxthread) {
+	if ((val > maxthread_local - 5 && uid != 0) ||
+	    val > maxthread_local) {
 		static struct timeval lasttfm;
 
 		if (ratecheck(&lasttfm, &fork_tfmrate))
@@ -353,7 +355,7 @@ fork1(struct proc *curp, int flags, void (*func)(void *), void *arg,
 	struct proc *p;
 	uid_t uid = curp->p_ucred->cr_ruid;
 	struct vmspace *vm;
-	int count;
+	int count, maxprocess_local;
 	vaddr_t uaddr;
 	int error;
 	struct  ptrace_state *newptstat = NULL;
@@ -366,8 +368,9 @@ fork1(struct proc *curp, int flags, void (*func)(void *), void *arg,
 	if ((error = fork_check_maxthread(uid)))
 		return error;
 
-	if ((nprocesses >= maxprocess - 5 && uid != 0) ||
-	    nprocesses >= maxprocess) {
+	maxprocess_local = atomic_load_int(&maxprocess);
+	if ((nprocesses >= maxprocess_local - 5 && uid != 0) ||
+	    nprocesses >= maxprocess_local) {
 		static struct timeval lasttfm;
 
 		if (ratecheck(&lasttfm, &fork_tfmrate))
diff --git a/sys/kern/kern_resource.c b/sys/kern/kern_resource.c
index c4fec1b4b6b..2afc6287f21 100644
--- a/sys/kern/kern_resource.c
+++ b/sys/kern/kern_resource.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_resource.c,v 1.86 2024/07/09 15:20:15 claudio Exp $	*/
+/*	$OpenBSD: kern_resource.c,v 1.87 2024/08/20 07:48:23 mvs Exp $	*/
 /*	$NetBSD: kern_resource.c,v 1.38 1996/10/23 07:19:38 matthias Exp $	*/
 
 /*-
@@ -278,7 +278,7 @@ dosetrlimit(struct proc *p, u_int which, struct rlimit *limp)
 		maxlim = maxfiles;
 		break;
 	case RLIMIT_NPROC:
-		maxlim = maxprocess;
+		maxlim = atomic_load_int(&maxprocess);
 		break;
 	default:
 		maxlim = RLIM_INFINITY;
diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 8b10fd14208..698548fbcf8 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sysctl.c,v 1.440 2024/08/20 07:44:36 mvs Exp $	*/
+/*	$OpenBSD: kern_sysctl.c,v 1.441 2024/08/20 07:48:23 mvs Exp $	*/
 /*	$NetBSD: kern_sysctl.c,v 1.17 1996/05/20 17:49:05 mrg Exp $	*/
 
 /*-
@@ -554,6 +554,7 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		return (sysctl_rdint(oldp, oldlenp, newp, mp->msg_bufs));
 	}
 	case KERN_OSREV:
+	case KERN_MAXPROC:
 	case KERN_NFILES:
 	case KERN_TTYCOUNT:
 	case KERN_ARGMAX:
@@ -563,6 +564,7 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 	case KERN_SAVED_IDS:
 	case KERN_MAXPARTITIONS:
 	case KERN_RAWPARTITION:
+	case KERN_MAXTHREAD:
 	case KERN_NTHREADS:
 	case KERN_SOMAXCONN:
 	case KERN_SOMINCONN: