Use integer offset math instead of pointer math to determine load
command bounds.

Upstream-URL: https://github.com/llvm/llvm-project/issues/56746

--- llvm-14.0.6.src/lib/Object/MachOObjectFile.cpp.old	2022-06-22 16:46:24.000000000 +0000
+++ llvm-14.0.6.src/lib/Object/MachOObjectFile.cpp	2022-11-28 04:21:02.730211841 +0000
@@ -190,7 +190,8 @@
 getLoadCommandInfo(const MachOObjectFile &Obj, const char *Ptr,
                    uint32_t LoadCommandIndex) {
   if (auto CmdOrErr = getStructOrErr<MachO::load_command>(Obj, Ptr)) {
-    if (CmdOrErr->cmdsize + Ptr > Obj.getData().end())
+    uint64_t Offset = Ptr - Obj.getData().begin();
+    if (CmdOrErr->cmdsize + Offset > Obj.getData().size())
       return malformedError("load command " + Twine(LoadCommandIndex) +
                             " extends past end of file");
     if (CmdOrErr->cmdsize < 8)