From 61268f23daa4c166e574eb33f00d1ddebf981f91 Mon Sep 17 00:00:00 2001
From: christos <christos@NetBSD.org>
Date: Sun, 30 Dec 2018 01:48:37 +0000
Subject: [PATCH] binutils 2.31.1 can put copy relocations in the relro
 segment. Delay protecting the relro segment for the main object until copy
 relocations are done.

---
 libexec/ld.elf_so/reloc.c | 22 +++++++++-------------
 libexec/ld.elf_so/rtld.c  | 23 +++++++++++++++++++++--
 libexec/ld.elf_so/rtld.h  |  4 +++-
 3 files changed, 33 insertions(+), 16 deletions(-)

diff --git a/libexec/ld.elf_so/reloc.c b/libexec/ld.elf_so/reloc.c
index 425fc0c259e6..4b9ba49ef264 100644
--- a/libexec/ld.elf_so/reloc.c
+++ b/libexec/ld.elf_so/reloc.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: reloc.c,v 1.113 2018/10/17 23:36:58 joerg Exp $	 */
+/*	$NetBSD: reloc.c,v 1.114 2018/12/30 01:48:37 christos Exp $	 */
 
 /*
  * Copyright 1996 John D. Polstra.
@@ -39,7 +39,7 @@
 
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: reloc.c,v 1.113 2018/10/17 23:36:58 joerg Exp $");
+__RCSID("$NetBSD: reloc.c,v 1.114 2018/12/30 01:48:37 christos Exp $");
 #endif /* not lint */
 
 #include <err.h>
@@ -102,10 +102,10 @@ _rtld_do_copy_relocation(const Obj_Entry *dstobj, const Elf_Rela *rela)
 		return (-1);
 	}
 	srcaddr = (const void *)(srcobj->relocbase + srcsym->st_value);
-	(void)memcpy(dstaddr, srcaddr, size);
 	rdbg(("COPY %s %s %s --> src=%p dst=%p size %ld",
 	    dstobj->path, srcobj->path, name, srcaddr,
 	    (void *)dstaddr, (long)size));
+	(void)memcpy(dstaddr, srcaddr, size);
 	return (0);
 }
 #endif /* RTLD_INHIBIT_COPY_RELOCS */
@@ -149,6 +149,10 @@ _rtld_do_copy_relocations(const Obj_Entry *dstobj)
 			}
 		}
 	}
+#ifdef GNU_RELRO
+	if (_rtld_relro(dstobj, true) == -1)
+		return -1;
+#endif
 #endif /* RTLD_INHIBIT_COPY_RELOCS */
 
 	return (0);
@@ -225,18 +229,10 @@ _rtld_relocate_objects(Obj_Entry *first, bool bind_now)
 		if (obj->pltgot != NULL)
 			_rtld_setup_pltgot(obj);
 #ifdef GNU_RELRO
-		if (obj->relro_size > 0) {
-			if (mprotect(obj->relro_page, obj->relro_size,
-			    PROT_READ) == -1) {
-				_rtld_error("%s: Cannot enforce relro "
-				    "protection: %s", obj->path,
-				    xstrerror(errno));
-				return -1;
-			}
-		}
+		if (_rtld_relro(obj, false) == -1)
+			return -1;
 #endif
 	}
-
 	return 0;
 }
 
diff --git a/libexec/ld.elf_so/rtld.c b/libexec/ld.elf_so/rtld.c
index e4f411421f72..ff45dacaf371 100644
--- a/libexec/ld.elf_so/rtld.c
+++ b/libexec/ld.elf_so/rtld.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: rtld.c,v 1.194 2018/12/27 18:57:43 christos Exp $	 */
+/*	$NetBSD: rtld.c,v 1.195 2018/12/30 01:48:37 christos Exp $	 */
 
 /*
  * Copyright 1996 John D. Polstra.
@@ -40,7 +40,7 @@
 
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: rtld.c,v 1.194 2018/12/27 18:57:43 christos Exp $");
+__RCSID("$NetBSD: rtld.c,v 1.195 2018/12/30 01:48:37 christos Exp $");
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -1746,3 +1746,22 @@ _rtld_exclusive_exit(sigset_t *mask)
 
 	sigprocmask(SIG_SETMASK, mask, NULL);
 }
+
+int
+_rtld_relro(const Obj_Entry *obj, bool wantmain)
+{
+#ifdef GNU_RELRO
+	if (obj->relro_size == 0)
+		return 0;
+	if (wantmain != (obj ==_rtld_objmain))
+		return 0;
+
+	dbg(("RELRO %s %p %lx\n", obj->path, obj->relro_page, obj->relro_size));
+	if (mprotect(obj->relro_page, obj->relro_size, PROT_READ) == -1) {
+		_rtld_error("%s: Cannot enforce relro " "protection: %s",
+		    obj->path, xstrerror(errno));
+		return -1;
+	}
+#endif
+	return 0;
+}
diff --git a/libexec/ld.elf_so/rtld.h b/libexec/ld.elf_so/rtld.h
index 3219b2bb9a36..ade7e4147993 100644
--- a/libexec/ld.elf_so/rtld.h
+++ b/libexec/ld.elf_so/rtld.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: rtld.h,v 1.135 2018/11/26 17:40:26 joerg Exp $	 */
+/*	$NetBSD: rtld.h,v 1.136 2018/12/30 01:48:37 christos Exp $	 */
 
 /*
  * Copyright 1996 John D. Polstra.
@@ -372,6 +372,8 @@ void _rtld_shared_exit(void);
 void _rtld_exclusive_enter(sigset_t *);
 void _rtld_exclusive_exit(sigset_t *);
 
+int _rtld_relro(const Obj_Entry *, bool);
+
 /* expand.c */
 size_t _rtld_expand_path(char *, size_t, const char *, const char *,\
     const char *);