Fix dyld opcode *_ADD_ADDR_IMM_SCALED error detection.

Summary: 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. Reviewers: pete, ab, lhames, steven_wu, jhenderson Reviewed By: pete Subscribers: hiraditya, dexonsmith, rupprecht, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D75629
llvm · Mar 5, 2020 · df05869 · df05869
1 parent cc61283
commit df05869
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Showing 2 changed files with 6 additions and 28 deletions.
diff --git a/llvm/lib/Object/MachOObjectFile.cpp b/llvm/lib/Object/MachOObjectFile.cpp
@@ -3214,6 +3214,7 @@ void MachORebaseEntry::moveNext() {
                                        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 @@ void MachORebaseEntry::moveNext() {
         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 @@ void MachOBindEntry::moveNext() {
         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 @@ void MachOBindEntry::moveNext() {
       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;
       }

diff --git a/llvm/test/tools/llvm-objdump/macho-bad-bind.test b/llvm/test/tools/llvm-objdump/macho-bad-bind.test
@@ -35,7 +35,7 @@ RUN: not llvm-objdump -macho -bind %p/Inputs/macho-bind-bind-add-addr-uleb 2>&1
 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 @@ RUN: not llvm-objdump -macho -rebase %p/Inputs/macho-rebase-add-addr-uleb 2>&1 |
 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)