1 files changed, 9 insertions, 1 deletions

diff --git a/lib/libmemstat/memstat_uma.c b/lib/libmemstat/memstat_uma.c
index 10ff8ec36a813..302093744b5c0 100644
--- a/lib/libmemstat/memstat_uma.c
+++ b/lib/libmemstat/memstat_uma.c
@@ -45,6 +45,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "memstat.h"
 #include "memstat_internal.h"
@@ -315,6 +316,7 @@ memstat_kvm_uma(struct memory_type_list *list, void *kvm_handle)
 	int hint_dontsearch, i, mp_maxid, ret;
 	char name[MEMTYPE_MAXNAME];
 	cpuset_t all_cpus;
+	long cpusetsize;
 	kvm_t *kvm;
 
 	kvm = (kvm_t *)kvm_handle;
@@ -338,7 +340,13 @@ memstat_kvm_uma(struct memory_type_list *list, void *kvm_handle)
 		list->mtl_error = ret;
 		return (-1);
 	}
-	ret = kread_symbol(kvm, X_ALL_CPUS, &all_cpus, sizeof(all_cpus), 0);
+	cpusetsize = sysconf(_SC_CPUSET_SIZE);
+	if (cpusetsize == -1 || (u_long)cpusetsize > sizeof(cpuset_t)) {
+		list->mtl_error = MEMSTAT_ERROR_KVM_NOSYMBOL;
+		return (-1);
+	}
+	CPU_ZERO(&all_cpus);
+	ret = kread_symbol(kvm, X_ALL_CPUS, &all_cpus, cpusetsize, 0);
 	if (ret != 0) {
 		list->mtl_error = ret;
 		return (-1);