[BOLT] Incorporate umask into the output file permission

[Kepontry]

Summary

Fix https://github.com/llvm/llvm-project/issues/65061

[Amir]

Thank you for taking care of it. Can you please also add a test?

[Amir]

This comment was removed by Amir.

[Kepontry]

Add a testcase.

[Amir]

Thank you for the fix and the test!

bolt/lib/Rewrite/MachORewriteInstance.cpp

void MachORewriteInstance::rewriteFile() {
   writeInstrumentationSection("I__setup", OS);
   writeInstrumentationSection("I__fini", OS);
   writeInstrumentationSection("I__data", OS);
   writeInstrumentationSection("I__text", OS);
   writeInstrumentationSection("I__cstring", OS);
   writeInstrumentationSection("I__literal16", OS);
 
   Out->keep();
-  EC = sys::fs::setPermissions(opts::OutputFilename,
-                               sys::fs::perms::all_all);
+  EC = sys::fs::setPermissions(
+      opts::OutputFilename,
+      static_cast<sys::fs::perms>(sys::fs::perms::all_all &
+                                  ~sys::fs::getUmask()));
   check_error(EC, "cannot set permissions of output file");
 }
 
 void MachORewriteInstance::adjustCommandLineOptions() {
 //FIXME! Upstream change
 //  opts::CheckOverlappingElements = false;
   if (!opts::AlignText.getNumOccurrences())
     opts::AlignText = BC->PageAlign;

bolt/lib/Rewrite/RewriteInstance.cpp

void RewriteInstance::rewriteFile() {
   patchELFSectionHeaderTable();
 
   if (opts::PrintSections) {
     outs() << "BOLT-INFO: Sections after processing:\n";
     BC->printSections(outs());
   }
 
   Out->keep();
-  EC = sys::fs::setPermissions(opts::OutputFilename, sys::fs::perms::all_all);
+  EC = sys::fs::setPermissions(
+      opts::OutputFilename,
+      static_cast<sys::fs::perms>(sys::fs::perms::all_all &
+                                  ~sys::fs::getUmask()));
   check_error(EC, "cannot set permissions of output file");
 }
 
 void RewriteInstance::writeEHFrameHeader() {
   BinarySection *NewEHFrameSection =
       getSection(getNewSecPrefix() + getEHFrameSectionName());
 
   // No need to update the header if no new .eh_frame was created.

bolt/test/permission.test

+# Ensure that the permissions of the optimized binary file comply with the
+# system's umask.
+
+# This test performs a logical AND operation on the results of the `stat -c %a
+# %t.bolt` and `umask` commands (both results are displayed in octal), and
+# checks whether the result is equal to 0.
+REQUIRES: system-linux
+
+RUN: %clang %cflags %p/Inputs/hello.c -o %t -Wl,-q
+RUN: llvm-bolt %t -o %t.bolt
+RUN: echo $(( 8#$(stat -c %a %t.bolt) & 8#$(umask) )) | FileCheck %s
+
+CHECK: 0