[PATCH] D75629: Fix dyld opcode *_ADD_ADDR_IMM_SCALED error detection.

[Michael Trent via Phabricator via llvm-commits]

mtrent created this revision.
mtrent added reviewers: pete, ab, lhames, steven_wu.
Herald added subscribers: rupprecht, dexonsmith, hiraditya.
Herald added a reviewer: jhenderson.
Herald added a project: LLVM.

Move the check for malformed REBASE_OPCODE_ADD_ADDR_IMM_SCALED and
BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED opcodes after the immediate
has been applied to the SegmentOffset. This fixes specious errors
where SegmentOffset is pointing between two sections when trying to
correct the SegmentOffset value.

Update the regression tests to verify the proper error message.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D75629

Files:
  llvm/lib/Object/MachOObjectFile.cpp
  llvm/test/tools/llvm-objdump/macho-bad-bind.test


Index: llvm/test/tools/llvm-objdump/macho-bad-bind.test
===================================================================
--- llvm/test/tools/llvm-objdump/macho-bad-bind.test
+++ llvm/test/tools/llvm-objdump/macho-bad-bind.test
@@ -35,7 +35,7 @@
 ADD-ADDR-ULEB: macho-bind-bind-add-addr-uleb': truncated or malformed object (for BIND_OPCODE_ADD_ADDR_ULEB (after adding ULEB) bad offset, not in section for opcode at: 0x18)
 
 RUN: not llvm-objdump -macho -bind %p/Inputs/macho-bind-add-addr-imm-scaled 2>&1 | FileCheck -check-prefix ADD-ADDR-IMM-SCALED %s
-ADD-ADDR-IMM-SCALED: macho-bind-add-addr-imm-scaled': truncated or malformed object (for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED  (after adding immediate times the pointer size) bad offset, not in section for opcode at: 0x17)
+ADD-ADDR-IMM-SCALED: macho-bind-add-addr-imm-scaled': truncated or malformed object (for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED bad offset, not in section for opcode at: 0x17)
 
 RUN: not llvm-objdump -macho -bind %p/Inputs/macho-bind-uleb-times-skipping-uleb 2>&1 | FileCheck -check-prefix ULEB-TIMES-SKIPPING-ULEB %s
 ULEB-TIMES-SKIPPING-ULEB: macho-bind-uleb-times-skipping-uleb': truncated or malformed object (for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB bad offset, not in section for opcode at: 0x17)
@@ -83,7 +83,7 @@
 REBASE-ADD-ADDR-ULEB: macho-rebase-add-addr-uleb': truncated or malformed object (for REBASE_OPCODE_ADD_ADDR_ULEB bad offset, not in section for opcode at: 0x3)
 
 RUN: not llvm-objdump -macho -rebase %p/Inputs/macho-rebase-add-addr-imm-scaled 2>&1 | FileCheck -check-prefix REBASE-ADD-ADDR-IMM-SCALED %s
-REBASE-ADD-ADDR-IMM-SCALED: macho-rebase-add-addr-imm-scaled': truncated or malformed object (for REBASE_OPCODE_ADD_ADDR_IMM_SCALED  (after adding immediate times the pointer size) bad offset, not in section for opcode at: 0x3)
+REBASE-ADD-ADDR-IMM-SCALED: macho-rebase-add-addr-imm-scaled': truncated or malformed object (for REBASE_OPCODE_ADD_ADDR_IMM_SCALED bad offset, not in section for opcode at: 0x3)
 
 RUN: not llvm-objdump -macho -rebase %p/Inputs/macho-rebase-imm-times 2>&1 | FileCheck -check-prefix REBASE-IMM-TIMES %s
 REBASE-IMM-TIMES: macho-rebase-imm-times': truncated or malformed object (for REBASE_OPCODE_DO_REBASE_IMM_TIMES bad offset, not in section for opcode at: 0x3)
Index: llvm/lib/Object/MachOObjectFile.cpp
===================================================================
--- llvm/lib/Object/MachOObjectFile.cpp
+++ llvm/lib/Object/MachOObjectFile.cpp
@@ -3214,6 +3214,7 @@
                                        SegmentOffset) << "\n");
       break;
     case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
+      SegmentOffset += ImmValue * PointerSize;
       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
                                                PointerSize);
       if (error) {
@@ -3223,18 +3224,6 @@
         moveToEnd();
         return;
       }
-      SegmentOffset += ImmValue * PointerSize;
-      error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
-                                               PointerSize);
-      if (error) {
-        *E =
-            malformedError("for REBASE_OPCODE_ADD_ADDR_IMM_SCALED "
-                           " (after adding immediate times the pointer size) " +
-                           Twine(error) + " for opcode at: 0x" +
-                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
-        moveToEnd();
-        return;
-      }
       DEBUG_WITH_TYPE("mach-o-rebase",
                       dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: "
                              << format("SegmentOffset=0x%06X",
@@ -3803,15 +3792,6 @@
         moveToEnd();
         return;
       }
-      error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
-                                             PointerSize);
-      if (error) {
-        *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED " +
-                            Twine(error) + " for opcode at: 0x" +
-                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
-        moveToEnd();
-        return;
-      }
       if (SymbolName == StringRef()) {
         *E = malformedError(
             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
@@ -3835,11 +3815,9 @@
       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
                                              AdvanceAmount, PointerSize);
       if (error) {
-        *E =
-            malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
-                           " (after adding immediate times the pointer size) " +
-                           Twine(error) + " for opcode at: 0x" +
-                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
+        *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED " +
+                            Twine(error) + " for opcode at: 0x" +
+                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
         moveToEnd();
         return;
       }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D75629.248255.patch
Type: text/x-patch
Size: 5086 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20200304/11f483eb/attachment.bin>