diff --git a/mm/umm_heap/umm_sbrk.c b/mm/umm_heap/umm_sbrk.c
index d633af3d97..3bee8db034 100644
--- a/mm/umm_heap/umm_sbrk.c
+++ b/mm/umm_heap/umm_sbrk.c
@@ -85,5 +85,5 @@
 
 FAR void *sbrk(intptr_t incr)
 {
-  return mm_sbrk(USR_HEAP, incr, CONFIG_ARCH_HEAP_NPAGES << MM_PGSHIFT);
+  return mm_sbrk(USR_HEAP, incr, ARCH_HEAP_VEND);
 }