diff --git a/core/elf.c b/core/elf.c
index ab9a559..0e481c3 100644
--- a/core/elf.c
+++ b/core/elf.c
@@ -148,7 +148,7 @@ uaddr_t loadElfProg(const char *prog, struct process *proc)
         // Hack: Even if already allocated mark the adresse space as managed by a ressource
         // So this address space is not used by another ressource.
         uaddr = elf_phdrs[i].p_vaddr;
-        zeroMmap(as, &uaddr, elf_phdrs[i].p_memsz, PAGING_MEM_USER | PAGING_MEM_WRITE | PAGING_MEM_READ, 0);
+        assert(zeroMmap(as, &uaddr, elf_phdrs[i].p_memsz, PAGING_MEM_USER | PAGING_MEM_WRITE | PAGING_MEM_READ, 0) == 0);
     }
 
     processInitHeap(proc, lastUserAddr);
diff --git a/core/uaddrspace.c b/core/uaddrspace.c
index 3d1e6d8..885e462 100644
--- a/core/uaddrspace.c
+++ b/core/uaddrspace.c
@@ -216,7 +216,8 @@ int uAddrSpaceUnmap(struct uAddrSpace *as, uaddr_t uaddr, size_t size)
                 reg->res->ops->unmap(reg, uaddr, size);
             break;
             // Only affect the end
-        } else if (uaddr > reg->addr && uaddr + size > reg->addr + reg->size) {
+        } else if (uaddr > reg->addr && uaddr < reg->addr + size &&
+                   uaddr + size > reg->addr + reg->size) {
             size_t unmapSize = reg->addr + reg->size - uaddr;
             reg->size        = uaddr - reg->addr;
 
@@ -306,7 +307,13 @@ int uAddrSpaceHeapCheckNAlloc(struct uAddrSpace *as, vaddr_t addr)
     newReg->size = PAGE_SIZE;
     newReg->right = right;
 
-    list_add_tail_named(as->listVirtualReg, newReg, nextInAddrSpace, prevInAddrSpace);
+    // keep the AS list sorted
+    struct uAddrVirtualReg *prev = findVirtualRegionBeforeAddr(as, addrAlign);
+    if (prev)
+        list_insert_after_named(as->listVirtualReg, prev, newReg, prevInAddrSpace,
+                                nextInAddrSpace);
+    else
+        list_add_tail_named(as->listVirtualReg, newReg, nextInAddrSpace, prevInAddrSpace);
 
     unrefPhyPage(ppage);