[Object, COFF] An import data directory might not consist soley of imports

The last import is the penultimate entry, the last entry is nulled out.
Data beyond the null entry should not be considered to hold import
entries.

This fixes PR28302.

N.B.  I am working on a reduced testcase, the one in PR28302 is too
large.

llvm-svn: 273790

1 files changed, 16 insertions, 10 deletions

diff --git a/llvm/tools/llvm-objdump/COFFDump.cpp b/llvm/tools/llvm-objdump/COFFDump.cpp
index 4f1b9b11913..3ec6a1f7375 100644
--- a/llvm/tools/llvm-objdump/COFFDump.cpp
+++ b/llvm/tools/llvm-objdump/COFFDump.cpp
@@ -352,11 +352,11 @@ static void printImportTables(const COFFObjectFile *Obj) {
   if (I == E)
     return;
   outs() << "The Import Tables:\n";
-  for (; I != E; I = ++I) {
+  for (const ImportDirectoryEntryRef &DirRef : Obj->import_directories()) {
     const import_directory_table_entry *Dir;
     StringRef Name;
-    if (I->getImportTableEntry(Dir)) return;
-    if (I->getName(Name)) return;
+    if (DirRef.getImportTableEntry(Dir)) return;
+    if (DirRef.getName(Name)) return;
 
     outs() << format("  lookup %08x time %08x fwd %08x name %08x addr %08x\n\n",
                      static_cast<uint32_t>(Dir->ImportLookupTableRVA),
@@ -366,17 +366,23 @@ static void printImportTables(const COFFObjectFile *Obj) {
                      static_cast<uint32_t>(Dir->ImportAddressTableRVA));
     outs() << "    DLL Name: " << Name << "\n";
     outs() << "    Hint/Ord  Name\n";
-    const import_lookup_table_entry32 *entry;
-    if (I->getImportLookupEntry(entry))
-      return;
-    for (; entry->Data; ++entry) {
-      if (entry->isOrdinal()) {
-        outs() << format("      % 6d\n", entry->getOrdinal());
+    for (const ImportedSymbolRef &Entry : DirRef.imported_symbols()) {
+      bool IsOrdinal;
+      if (Entry.isOrdinal(IsOrdinal))
+        return;
+      if (IsOrdinal) {
+        uint16_t Ordinal;
+        if (Entry.getOrdinal(Ordinal))
+          return;
+        outs() << format("      % 6d\n", Ordinal);
         continue;
       }
+      uint32_t HintNameRVA;
+      if (Entry.getHintNameRVA(HintNameRVA))
+        return;
       uint16_t Hint;
       StringRef Name;
-      if (Obj->getHintName(entry->getHintNameRVA(), Hint, Name))
+      if (Obj->getHintName(HintNameRVA, Hint, Name))
         return;
       outs() << format("      % 6d  ", Hint) << Name << "\n";
     }