Don't read one command past the end.

Thanks to Evgeniy Stepanov for reporting this. It might be a good idea to add a command iterator abstraction to MachO.h, but this fixes the bug for now. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179848 91177308-0d34-0410-b5e6-96231b3b80d8
compnerd · Apr 19, 2013 · db5f927 · db5f927
1 parent 4521019
commit db5f927
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Showing 4 changed files with 16 additions and 4 deletions.
diff --git a/lib/Object/MachOObjectFile.cpp b/lib/Object/MachOObjectFile.cpp
@@ -405,7 +405,7 @@ MachOObjectFile::MachOObjectFile(MemoryBuffer *Object,
     macho::LCT_Segment64 : macho::LCT_Segment;
 
   MachOObjectFile::LoadCommandInfo Load = getFirstLoadCommandInfo();
-  for (unsigned I = 0; I < LoadCommandCount; ++I) {
+  for (unsigned I = 0; ; ++I) {
     if (Load.C.Type == macho::LCT_Symtab) {
       assert(!SymtabLoadCmd && "Multiple symbol tables");
       SymtabLoadCmd = Load.Ptr;
@@ -418,7 +418,11 @@ MachOObjectFile::MachOObjectFile(MemoryBuffer *Object,
         Sections.push_back(reinterpret_cast<const char*>(Sec));
       }
     }
-    Load = getNextLoadCommandInfo(Load);
+
+    if (I == LoadCommandCount - 1)
+      break;
+    else
+      Load = getNextLoadCommandInfo(Load);
   }
 }
 

diff --git a/test/Object/ARM/objdump-thumb.test b/test/Object/ARM/objdump-thumb.test
@@ -0,0 +1,4 @@
+RUN: llvm-objdump -d -macho -triple=thumbv7-apple-ios \
+RUN: %p/../Inputs/macho-text.thumb | FileCheck %s
+
+CHECK: 0:	00 bf                                        	nop
diff --git a/test/Object/Inputs/macho-text.thumb b/test/Object/Inputs/macho-text.thumb
diff --git a/tools/llvm-objdump/MachODump.cpp b/tools/llvm-objdump/MachODump.cpp
@@ -205,7 +205,7 @@ getSectionsAndSymbols(const macho::Header Header,
 
   MachOObjectFile::LoadCommandInfo Command =
     MachOObj->getFirstLoadCommandInfo();
-  for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
+  for (unsigned i = 0; ; ++i) {
     if (Command.C.Type == macho::LCT_FunctionStarts) {
       // We found a function starts segment, parse the addresses for later
       // consumption.
@@ -214,7 +214,11 @@ getSectionsAndSymbols(const macho::Header Header,
 
       MachOObj->ReadULEB128s(LLC.DataOffset, FoundFns);
     }
-    Command = MachOObj->getNextLoadCommandInfo(Command);
+
+    if (i == Header.NumLoadCommands - 1)
+      break;
+    else
+      Command = MachOObj->getNextLoadCommandInfo(Command);
   }
 }