diff --git a/lib/librte_eal/common/malloc_heap.c b/lib/librte_eal/common/malloc_heap.c
index 590e9e34be..5cf7231022 100644
--- a/lib/librte_eal/common/malloc_heap.c
+++ b/lib/librte_eal/common/malloc_heap.c
@@ -99,11 +99,12 @@ malloc_add_seg(const struct rte_memseg_list *msl,
 
 	/* msl is const, so find it */
 	msl_idx = msl - mcfg->memsegs;
-	found_msl = &mcfg->memsegs[msl_idx];
 
 	if (msl_idx < 0 || msl_idx >= RTE_MAX_MEMSEG_LISTS)
 		return -1;
 
+	found_msl = &mcfg->memsegs[msl_idx];
+
 	malloc_heap_add_memory(heap, found_msl, ms->addr, len);
 
 	RTE_LOG(DEBUG, EAL, "Added %zuM to heap on socket %i\n", len >> 20,