From: George Rimar <grimar@accesssoftek.com>
Date: Fri, 19 Aug 2016 15:46:28 +0000 (+0000)
Subject: [ELF] - Fix for PR28976 - Corrupted section contents when using linker scripts
X-Git-Tag: llvmorg-4.0.0-rc1~11923
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3e6833b4b236e46ccf304a7b118615036d7c582b;p=platform%2Fupstream%2Fllvm.git

[ELF] - Fix for PR28976 - Corrupted section contents when using linker scripts

This is fix for PR28976.

Problem was that in scanRelocs, we computed relocation offset too early
for case when linkerscript was used. Patch fixes the issue
delaying the calculation.

Differential revision: https://reviews.llvm.org/D23655

llvm-svn: 279264
---

diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 191832e..a699044 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -351,7 +351,7 @@ void InputSectionBase<ELFT>::relocate(uint8_t *Buf, uint8_t *BufEnd) {
 
   const unsigned Bits = sizeof(uintX_t) * 8;
   for (const Relocation<ELFT> &Rel : Relocations) {
-    uintX_t Offset = Rel.Offset;
+    uintX_t Offset = getOffset(Rel.Offset);
     uint8_t *BufLoc = Buf + Offset;
     uint32_t Type = Rel.Type;
     uintX_t A = Rel.Addend;
diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index 02539f5..2631ccc 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -1274,7 +1274,7 @@ template <class ELFT>
 typename ELFT::uint DynamicReloc<ELFT>::getOffset() const {
   if (OutputSec)
     return OutputSec->getVA() + OffsetInSec;
-  return InputSec->OutSec->getVA() + OffsetInSec;
+  return InputSec->OutSec->getVA() + InputSec->getOffset(OffsetInSec);
 }
 
 template <class ELFT>
diff --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index dca84e1..0f03857 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -566,7 +566,7 @@ static void scanRelocs(InputSectionBase<ELFT> &C, ArrayRef<RelTy> Rels) {
         continue;
       Offset = PieceI->OutputOff + RI.r_offset - PieceI->InputOff;
     } else {
-      Offset = C.getOffset(RI.r_offset);
+      Offset = RI.r_offset;
     }
 
     // This relocation does not require got entry, but it is relative to got and
diff --git a/lld/test/ELF/linkerscript/Inputs/linkerscript-merge-sections-reloc.s b/lld/test/ELF/linkerscript/Inputs/linkerscript-merge-sections-reloc.s
new file mode 100644
index 0000000..07e599b
--- /dev/null
+++ b/lld/test/ELF/linkerscript/Inputs/linkerscript-merge-sections-reloc.s
@@ -0,0 +1,3 @@
+.globl _start
+_start:
+ .quad 0x11223344
diff --git a/lld/test/ELF/linkerscript/linkerscript-merge-sections-reloc.s b/lld/test/ELF/linkerscript/linkerscript-merge-sections-reloc.s
new file mode 100644
index 0000000..9d8089a
--- /dev/null
+++ b/lld/test/ELF/linkerscript/linkerscript-merge-sections-reloc.s
@@ -0,0 +1,16 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %p/Inputs/linkerscript-merge-sections-reloc.s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t2.o
+# RUN: echo "SECTIONS {}" > %t.script
+# RUN: ld.lld -o %t --script %t.script %t1.o %t2.o
+# RUN: llvm-objdump -s %t | FileCheck %s
+
+## Check that sections content is not corrupted.
+# CHECK:      Contents of section .text:
+# CHECK-NEXT:  44332211 00000000 44332211 00000000
+# CHECK-NEXT:  f0ffffff ffffffff
+
+.globl _start
+_foo:
+ .quad 0x11223344
+ .quad _start - .