diff --git a/libc/malloc_debug/MapData.cpp b/libc/malloc_debug/MapData.cpp
index e8fbc5401..ded81a2d5 100644
--- a/libc/malloc_debug/MapData.cpp
+++ b/libc/malloc_debug/MapData.cpp
@@ -116,14 +116,17 @@ static void read_loadbias(MapEntry* entry) {
     if (!get_val<ElfW(Word)>(entry, addr + offsetof(ElfW(Phdr), p_type), &phdr.p_type)) {
       return;
     }
+    if (!get_val<ElfW(Word)>(entry, addr + offsetof(ElfW(Phdr), p_flags), &phdr.p_flags)) {
+      return;
+    }
     if (!get_val<ElfW(Off)>(entry, addr + offsetof(ElfW(Phdr), p_offset), &phdr.p_offset)) {
       return;
     }
-    if (phdr.p_type == PT_LOAD && phdr.p_offset == entry->offset) {
+    if ((phdr.p_type == PT_LOAD) && (phdr.p_flags & PF_X) ) {
       if (!get_val<ElfW(Addr)>(entry, addr + offsetof(ElfW(Phdr), p_vaddr), &phdr.p_vaddr)) {
         return;
       }
-      entry->load_bias = phdr.p_vaddr;
+      entry->load_bias = phdr.p_vaddr - phdr.p_offset;
       return;
     }
     addr += sizeof(phdr);