diff --git a/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp b/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
--- a/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
+++ b/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
@@ -1433,7 +1433,7 @@
   uint32_t result = 0;
   if (seg_cmd.initprot & VM_PROT_READ)
     result |= ePermissionsReadable;
-  if (seg_cmd.initprot & VM_PROT_WRITE)
+  if ((seg_cmd.initprot & VM_PROT_WRITE) && !(seg_cmd.flags & SG_READ_ONLY))
     result |= ePermissionsWritable;
   if (seg_cmd.initprot & VM_PROT_EXECUTE)
     result |= ePermissionsExecutable;
diff --git a/llvm/include/llvm/BinaryFormat/MachO.h b/llvm/include/llvm/BinaryFormat/MachO.h
--- a/llvm/include/llvm/BinaryFormat/MachO.h
+++ b/llvm/include/llvm/BinaryFormat/MachO.h
@@ -106,6 +106,7 @@
   SG_FVMLIB = 0x2u,
   SG_NORELOC = 0x4u,
   SG_PROTECTED_VERSION_1 = 0x8u,
+  SG_READ_ONLY = 0x10u,
 
   // Constant masks for the "flags" field in llvm::MachO::section and
   // llvm::MachO::section_64