[PATCH] D36140: [ELF] - Do not segfault if linkerscript tries to access Target too early.

[George Rimar via Phabricator via llvm-commits]

grimar updated this revision to Diff 109103.
grimar added a comment.

- Addressed review comment.


https://reviews.llvm.org/D36140

Files:
  ELF/ScriptParser.cpp
  test/ELF/linkerscript/memory-err.s


Index: test/ELF/linkerscript/memory-err.s
===================================================================
--- test/ELF/linkerscript/memory-err.s
+++ test/ELF/linkerscript/memory-err.s
@@ -0,0 +1,10 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: echo "MEMORY { name : ORIGIN = DATA_SEGMENT_RELRO_END; }" > %t.script
+# RUN: not ld.lld -shared -o %t2 --script %t.script %t 2>&1 | FileCheck %s
+# CHECK: error: {{.*}}.script:1: unable to calculate page size
+
+# RUN: echo "MEMORY { name : ORIGIN = CONSTANT(COMMONPAGESIZE); }" > %t.script
+# RUN: not ld.lld -shared -o %t2 --script %t.script %t 2>&1 |\
+# RUN:   FileCheck %s --check-prefix=ERR2
+# ERR2: error: {{.*}}.script:1: unable to calculate page size
Index: ELF/ScriptParser.cpp
===================================================================
--- ELF/ScriptParser.cpp
+++ ELF/ScriptParser.cpp
@@ -793,9 +793,17 @@
   return Lhs;
 }
 
-uint64_t static getConstant(StringRef S) {
-  if (S == "COMMONPAGESIZE")
+static uint64_t getPageSize(StringRef Location) {
+  if (Target)
     return Target->PageSize;
+  error(Location + ": unable to calculate page size");
+  // Result value may be used in align(), and alignment can't be 0.
+  return 1;
+}
+
+uint64_t static getConstant(StringRef S, StringRef Location) {
+  if (S == "COMMONPAGESIZE")
+    return getPageSize(Location);
   if (S == "MAXPAGESIZE")
     return Config->MaxPageSize;
   error("unknown constant: " + S);
@@ -921,7 +929,7 @@
     return readAssertExpr();
   if (Tok == "CONSTANT") {
     StringRef Name = readParenLiteral();
-    return [=] { return getConstant(Name); };
+    return [=] { return getConstant(Name, Location); };
   }
   if (Tok == "DATA_SEGMENT_ALIGN") {
     expect("(");
@@ -948,7 +956,7 @@
     expect(",");
     readExpr();
     expect(")");
-    return [] { return alignTo(Script->getDot(), Target->PageSize); };
+    return [=] { return alignTo(Script->getDot(), getPageSize(Location)); };
   }
   if (Tok == "DEFINED") {
     StringRef Name = readParenLiteral();


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D36140.109103.patch
Type: text/x-patch
Size: 2067 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20170801/222ee359/attachment.bin>