From 39913f32de3b9b7afe06cdf560ce42d1cc49be53 Mon Sep 17 00:00:00 2001
From: Peter Johnson <peter@tortall.net>
Date: Sat, 15 Sep 2007 06:40:27 +0000
Subject: [PATCH] Fix #114: Incorrect ELF32 ..gotpc address calculation.
 Reported by: Loren Merritt Fix by: mu@

We already had a testcase for this, but it had an incorrect "golden" result.

svn path=/trunk/yasm/; revision=1952
---
 modules/objfmts/elf/elf-machine.h   |  5 +++++
 modules/objfmts/elf/elf-objfmt.c    |  2 ++
 modules/objfmts/elf/elf-x86-amd64.c |  4 ++--
 modules/objfmts/elf/elf-x86-x86.c   |  4 ++--
 modules/objfmts/elf/elf.c           | 16 +++++++++++++++-
 modules/objfmts/elf/elf.h           |  1 +
 modules/objfmts/elf/tests/elfso.hex |  8 ++++----
 7 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/modules/objfmts/elf/elf-machine.h b/modules/objfmts/elf/elf-machine.h
index 562e098c..f2bb8db7 100644
--- a/modules/objfmts/elf/elf-machine.h
+++ b/modules/objfmts/elf/elf-machine.h
@@ -69,6 +69,11 @@ typedef void (*func_write_proghead)(unsigned char **bufpp,
                                     unsigned long secthead_count,
                                     elf_section_index shstrtab_index);
 
+enum {
+    ELF_SSYM_SYM_RELATIVE = 1 << 0,
+    ELF_SSYM_CURPOS_ADJUST = 1 << 1
+};
+
 typedef struct {
     const char *name;       /* should be something like ..name */
     const int sym_rel;      /* symbol or section-relative? */
diff --git a/modules/objfmts/elf/elf-objfmt.c b/modules/objfmts/elf/elf-objfmt.c
index 664d1351..5ec17b7c 100644
--- a/modules/objfmts/elf/elf-objfmt.c
+++ b/modules/objfmts/elf/elf-objfmt.c
@@ -514,6 +514,8 @@ elf_objfmt_output_value(yasm_value *value, unsigned char *buf,
             wrt = NULL;
         else if (wrt && elf_is_wrt_sym_relative(wrt))
             ;
+        else if (wrt && elf_is_wrt_pos_adjusted(wrt))
+            intn_val = offset + bc->offset;
         else if (vis == YASM_SYM_LOCAL) {
             yasm_bytecode *sym_precbc;
             /* Local symbols need relocation to their section's start, and
diff --git a/modules/objfmts/elf/elf-x86-amd64.c b/modules/objfmts/elf/elf-x86-amd64.c
index ce0cdda1..4bc53b21 100644
--- a/modules/objfmts/elf/elf-x86-amd64.c
+++ b/modules/objfmts/elf/elf-x86-amd64.c
@@ -209,8 +209,8 @@ elf_x86_amd64_write_proghead(unsigned char **bufpp,
 }
 
 static elf_machine_ssym elf_x86_amd64_ssyms[] = {
-    {"..gotpcrel", 1},
-    {"..got", 1},
+    {"..gotpcrel", ELF_SSYM_SYM_RELATIVE},
+    {"..got", ELF_SSYM_SYM_RELATIVE},
     {"..plt", 0}
 };
 
diff --git a/modules/objfmts/elf/elf-x86-x86.c b/modules/objfmts/elf/elf-x86-x86.c
index 827c861e..67a23d0a 100644
--- a/modules/objfmts/elf/elf-x86-x86.c
+++ b/modules/objfmts/elf/elf-x86-x86.c
@@ -194,9 +194,9 @@ elf_x86_x86_write_proghead(unsigned char **bufpp,
 }
 
 static elf_machine_ssym elf_x86_x86_ssyms[] = {
-    {"..gotpc", 0},
+    {"..gotpc", ELF_SSYM_CURPOS_ADJUST},
     {"..gotoff", 0},
-    {"..got", 1},
+    {"..got", ELF_SSYM_SYM_RELATIVE},
     {"..plt", 0}
 };
 
diff --git a/modules/objfmts/elf/elf.c b/modules/objfmts/elf/elf.c
index f187b9e7..87ee9828 100644
--- a/modules/objfmts/elf/elf.c
+++ b/modules/objfmts/elf/elf.c
@@ -99,13 +99,27 @@ elf_set_arch(yasm_arch *arch, yasm_symtab *symtab, int bits_pref)
 }
 
 /* reloc functions */
+int elf_ssym_has_flag(yasm_symrec *wrt, int flag);
+
 int
 elf_is_wrt_sym_relative(yasm_symrec *wrt)
+{
+    return elf_ssym_has_flag(wrt, ELF_SSYM_SYM_RELATIVE);
+}
+
+int
+elf_is_wrt_pos_adjusted(yasm_symrec *wrt)
+{
+    return elf_ssym_has_flag(wrt, ELF_SSYM_CURPOS_ADJUST);
+}
+
+int
+elf_ssym_has_flag(yasm_symrec *wrt, int flag)
 {
     int i;
     for (i=0; (unsigned int)i<elf_march->num_ssyms; i++) {
         if (elf_ssyms[i] == wrt)
-            return elf_march->ssyms[i].sym_rel;
+            return (elf_march->ssyms[i].sym_rel & flag) != 0;
     }
     return 0;
 }
diff --git a/modules/objfmts/elf/elf.h b/modules/objfmts/elf/elf.h
index b876a75e..954e052e 100644
--- a/modules/objfmts/elf/elf.h
+++ b/modules/objfmts/elf/elf.h
@@ -412,6 +412,7 @@ const elf_machine_handler *elf_set_arch(struct yasm_arch *arch,
 
 /* reloc functions */
 int elf_is_wrt_sym_relative(yasm_symrec *wrt);
+int elf_is_wrt_pos_adjusted(yasm_symrec *wrt);
 elf_reloc_entry *elf_reloc_entry_create(yasm_symrec *sym,
                                         /*@null@*/ yasm_symrec *wrt,
                                         yasm_intnum *addr,
diff --git a/modules/objfmts/elf/tests/elfso.hex b/modules/objfmts/elf/tests/elfso.hex
index 9d99c0f8..206cce9c 100644
--- a/modules/objfmts/elf/tests/elfso.hex
+++ b/modules/objfmts/elf/tests/elfso.hex
@@ -88,10 +88,10 @@ e8
 5b 
 81 
 c3 
-e9 
-ff 
-ff 
-ff 
+03 
+00 
+00 
+00 
 8b 
 83 
 00 
-- 
2.40.0