From 28071cd3c613a8143ef262d290c1be0610b8750c Mon Sep 17 00:00:00 2001
From: Max Wash <max@doorstuck.net>
Date: Thu, 11 Mar 2021 10:12:33 +0000
Subject: [PATCH] Fixed incorrect heap bounds

---
 photon/libc/sys/magenta/heap.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/photon/libc/sys/magenta/heap.c b/photon/libc/sys/magenta/heap.c
index 9a2d590..56c8cfb 100644
--- a/photon/libc/sys/magenta/heap.c
+++ b/photon/libc/sys/magenta/heap.c
@@ -14,19 +14,20 @@ static uintptr_t heap_alloc_point = 0;
 static size_t heap_sz = 0;
 static mx_handle_t heap_vmo = MX_NULL_HANDLE;
 
-void __crt_heap_init(size_t heap_sz)
+void __crt_heap_init(size_t sz)
 {
     mx_status_t status = mx_vmo_create(
-            heap_sz,
+            sz,
             MX_VM_CAN_MAP_READ | MX_VM_CAN_MAP_WRITE | MX_VM_CAN_MAP_SPECIFIC,
             &heap_vmo);
 
     mx_vaddr_t heap = 0;
     mx_vmar_map(mx_get_startup_handle(MX_B_VMAR_ROOT),
             MX_VM_PERM_READ | MX_VM_PERM_WRITE,
-            0, heap_vmo, 0, heap_sz,
+            0, heap_vmo, 0, sz,
             &heap);
 
+    heap_sz = sz;
     heap_start = heap;
     heap_end = heap + heap_sz;
     heap_alloc_point = heap_start;
@@ -41,20 +42,20 @@ void *__crt_heap_extend(size_t sz)
         sz += MX_PAGE_SIZE;
     }
 
+    if (!sz) {
+        return (void *)heap_end;
+    }
+
     if (!heap_start) {
         __crt_heap_init(sz);
         return (void *)heap_start;
     }
 
-    if (!sz) {
-        return (void *)heap_end;
-    }
-
     mx_vmo_set_size(heap_vmo, heap_sz + sz);
 
     mx_vaddr_t vmar_base, alloc_base;
     mx_vmar_bounds(mx_get_startup_handle(MX_B_VMAR_ROOT), &vmar_base, NULL);
-    mx_vaddr_t offset = heap_end - vmar_base;
+    size_t offset = heap_end - vmar_base;
 
     mx_vmar_map(mx_get_startup_handle(MX_B_VMAR_ROOT),
             MX_VM_PERM_READ | MX_VM_PERM_WRITE | MX_VM_SPECIFIC,