--- a/sys/vfs/procfs/procfs_mem.c
+++ b/sys/vfs/procfs/procfs_mem.c
@@ -99,6 +99,10 @@
 		reqprot |= VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE;
 
 	kva = kmem_alloc_pageable(kernel_map, PAGE_SIZE, VM_SUBSYS_PROC);
+	if (kva == 0) {
+		vmspace_drop(vm);
+		return (ENOMEM);
+	}
 
 	/*
 	 * Only map in one page at a time.  We don't have to, but it