[PATCH] Set __libc_stack_end earlier on all arches, export back at GLIBC_2.1

[Jakub Jelinek <jakub at redhat dot com>]

Hi!

Roland's execstack code needs __libc_stack_end set already during dl_main,
not after it.
The following patch does that (tested on a bunch of arches).
I haven't touched hppa, mips, can maintainers do something about it?
Also, for ia64, the __libc_stack_end setting code in RTLD_START should
be removed, but removing of that requires rebundling the whole assembly.
Any volunteers?

2003-09-24  Jakub Jelinek  <jakub@redhat.com>

	* elf/Versions (ld): Export __libc_stack_end@GLIBC_2.1 instead of
	__libc_stack_end@GLIBC_PRIVATE.

	* sysdeps/generic/dl-sysdep.c (DL_STACK_END): Define if not defined.
	(_dl_sysdep_start): Set __libc_stack_end here.
	* sysdeps/alpha/dl-machine.h (RTLD_START): Remove setting of
	__libc_stack_end.
	* sysdeps/arm/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/cris/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/m68k/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/s390/s390-32/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/s390/s390-64/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/sh/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/x86_64/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/ia64/dl-machine.h (DL_STACK_END): Define.
	* sysdeps/sparc/sparc32/dl-machine.h (DL_STACK_END): Define.
	(RTLD_START): Remove setting of __libc_stack_end.
	* sysdeps/sparc/sparc64/dl-machine.h (DL_STACK_END): Define.
	(RTLD_START): Remove setting of __libc_stack_end.

--- libc/elf/Versions.jj	2003-09-23 10:14:05.000000000 -0400
+++ libc/elf/Versions	2003-09-24 05:37:50.000000000 -0400
@@ -36,6 +36,8 @@ ld {
   GLIBC_2.1 {
     # functions used in other libraries
     _dl_mcount;
+    # historically used by Garbage Collectors
+    __libc_stack_end;
   }
   GLIBC_2.3 {
     # runtime interface to TLS
@@ -43,7 +45,7 @@ ld {
   }
   GLIBC_PRIVATE {
     # Those are in the dynamic linker, but used by libc.so.
-    __libc_enable_secure; __libc_stack_end;
+    __libc_enable_secure;
     _dl_argv; _dl_catch_error; _dl_check_map_versions;
     _dl_debug_printf; _dl_debug_state; _dl_dst_count;
     _dl_dst_substitute; _dl_init; _dl_lookup_symbol; _dl_lookup_symbol_skip;
--- libc/sysdeps/alpha/dl-machine.h.jj	2003-07-31 04:35:53.000000000 -0400
+++ libc/sysdeps/alpha/dl-machine.h	2003-09-24 04:34:21.000000000 -0400
@@ -319,8 +319,6 @@ _dl_start_user:							\n\
 	.prologue 0						\n\
 	/* Save the user entry point address in s0.  */		\n\
 	mov	$0, $9						\n\
-	/* Store the highest stack address.  */			\n\
-	stq	$30, __libc_stack_end				\n\
 	/* See if we were run as a command with the executable	\n\
 	   file name as an extra leading argument.  */		\n\
 	ldl	$1, _dl_skip_args($gp)	!gprel			\n\
--- libc/sysdeps/arm/dl-machine.h.jj	2003-09-22 11:35:41.000000000 -0400
+++ libc/sysdeps/arm/dl-machine.h	2003-09-24 04:35:37.000000000 -0400
@@ -265,10 +265,6 @@ _dl_start_user:\n\
 	ldr	sl, .L_GET_GOT\n\
 	add	sl, pc, sl\n\
 .L_GOT_GOT:\n\
-	@ Store the highest stack address\n\
-	ldr	r1, .L_STACK_END\n\
-	ldr	r1, [sl, r1]\n\
-	str	sp, [r1]\n\
 	@ See if we were run as a command with the executable file\n\
 	@ name as an extra leading argument.\n\
 	ldr	r4, .L_SKIP_ARGS\n\
@@ -311,8 +307,6 @@ _dl_start_user:\n\
 	.word	_dl_starting_up(GOT)\n\
 .L_FINI_PROC:\n\
 	.word	_dl_fini(GOT)\n\
-.L_STACK_END:\n\
-	.word	__libc_stack_end(GOT)\n\
 .L_LOADED:\n\
 	.word	_rtld_local(GOT)\n\
 .previous\n\
--- libc/sysdeps/cris/dl-machine.h.jj	2003-09-17 07:42:32.000000000 -0400
+++ libc/sysdeps/cris/dl-machine.h	2003-09-24 04:36:14.000000000 -0400
@@ -188,9 +188,6 @@ _dl_start_user:\n\
 	; Point R0 at the GOT.\n\
 	move.d	$pc,$r0\n\
 	sub.d	.:GOTOFF,$r0\n\
-	; Remember the highest stack address.\n\
-	move.d	[$r0+__libc_stack_end:GOT16],$r13\n\
-	move.d	$sp,[$r13]\n\
 	; See if we were run as a command with the executable file\n\
 	; name as an extra leading argument.\n\
 	move.d	[$r0+_dl_skip_args:GOT16],$r13\n\
--- libc/sysdeps/generic/dl-sysdep.c.jj	2003-07-15 11:14:39.000000000 -0400
+++ libc/sysdeps/generic/dl-sysdep.c	2003-09-24 04:31:10.000000000 -0400
@@ -69,6 +69,9 @@ static ElfW(auxv_t) *_dl_auxv;
   } while (0)
 #endif
 
+#ifndef DL_STACK_END
+# define DL_STACK_END(cookie) ((void *) (cookie))
+#endif
 
 ElfW(Addr)
 _dl_sysdep_start (void **start_argptr,
@@ -98,6 +101,7 @@ _dl_sysdep_start (void **start_argptr,
   ElfW(Word) new_sysinfo = 0;
 #endif
 
+  __libc_stack_end = DL_STACK_END (start_argptr);
   DL_FIND_ARG_COMPONENTS (start_argptr, _dl_argc, INTUSE(_dl_argv), _environ,
 			  _dl_auxv);
 
--- libc/sysdeps/i386/dl-machine.h.jj	2003-09-23 11:03:03.000000000 -0400
+++ libc/sysdeps/i386/dl-machine.h	2003-09-24 04:38:49.000000000 -0400
@@ -276,17 +276,15 @@ _dl_runtime_profile:\n\
 .globl _start\n\
 .globl _dl_start_user\n\
 _start:\n\
-	# Point %ebx at the GOT.\n\
-	call 0b\n\
-	addl $_GLOBAL_OFFSET_TABLE_, %ebx\n\
 	# Note that _dl_start gets the parameter in %eax.\n\
 	movl %esp, %eax\n\
-	# Store the highest stack address\n\
-	movl %eax, __libc_stack_end@GOTOFF(%ebx)\n\
 	call _dl_start\n\
 _dl_start_user:\n\
 	# Save the user entry point address in %edi.\n\
 	movl %eax, %edi\n\
+	# Point %ebx at the GOT.\n\
+	call 0b\n\
+	addl $_GLOBAL_OFFSET_TABLE_, %ebx\n\
 	# See if we were run as a command with the executable file\n\
 	# name as an extra leading argument.\n\
 	movl _dl_skip_args@GOTOFF(%ebx), %eax\n\
--- libc/sysdeps/ia64/dl-machine.h.jj	2003-08-26 17:07:43.000000000 -0400
+++ libc/sysdeps/ia64/dl-machine.h	2003-09-24 04:44:19.000000000 -0400
@@ -267,6 +267,10 @@ elf_machine_runtime_setup (struct link_m
   strong_alias (_dl_runtime_resolve, _dl_runtime_profile);
 #endif
 
+/* Undo the adds out0 = 16, sp below to get at the value we want in
+   __libc_stack_end.  */
+#define DL_STACK_END(cookie) \
+  ((void *) (((long) (cookie)) - 16))
 
 /* Initial entry point code for the dynamic linker.
    The C function `_dl_start' is the real entry point;
--- libc/sysdeps/m68k/dl-machine.h.jj	2003-07-31 04:35:58.000000000 -0400
+++ libc/sysdeps/m68k/dl-machine.h	2003-09-24 04:54:45.000000000 -0400
@@ -157,9 +157,6 @@ _start:\n\
 _dl_start_user:\n\
 	| Save the user entry point address in %a4.\n\
 	move.l %d0, %a4\n\
-	| Remember the highest stack address.\n\
-	move.l __libc_stack_end@GOTPC(%pc), %a0\n\
-	move.l %sp, (%a0)\n\
 	| See if we were run as a command with the executable file\n\
 	| name as an extra leading argument.\n\
 	move.l _dl_skip_args(%pc), %d0\n\
--- libc/sysdeps/s390/s390-32/dl-machine.h.jj	2003-08-06 14:36:16.000000000 -0400
+++ libc/sysdeps/s390/s390-32/dl-machine.h	2003-09-24 05:05:21.000000000 -0400
@@ -262,9 +262,6 @@ _dl_start_user:\n\
 	# Point %r12 at the GOT.\n\
 	l     %r12,.Ladr0-.Llit(%r13)\n\
 	ar    %r12,%r13\n\
-	# Store the highest stack address\n\
-	l     %r1,__libc_stack_end@GOT(%r12)\n\
-	st    %r15, 0(%r1)\n\
 	# See if we were run as a command with the executable file\n\
 	# name as an extra leading argument.\n\
 	l     %r1,_dl_skip_args@GOT12(0,%r12)\n\
--- libc/sysdeps/s390/s390-64/dl-machine.h.jj	2003-08-06 14:36:16.000000000 -0400
+++ libc/sysdeps/s390/s390-64/dl-machine.h	2003-09-24 05:05:55.000000000 -0400
@@ -235,10 +235,6 @@ _dl_start_user:\n\
 	lgr   %r8,%r2\n\
 	# Point %r12 at the GOT.\n\
 	larl  %r12,_GLOBAL_OFFSET_TABLE_\n\
-	# Store the highest stack address\n\
-	lghi  %r1,__libc_stack_end@GOT\n\
-	lg    %r1,0(%r1,%r12)\n\
-	stg   %r15, 0(%r1)\n\
 	# See if we were run as a command with the executable file\n\
 	# name as an extra leading argument.\n\
 	lghi  %r1,_dl_skip_args@GOT\n\
--- libc/sysdeps/sh/dl-machine.h.jj	2003-07-31 04:36:01.000000000 -0400
+++ libc/sysdeps/sh/dl-machine.h	2003-09-24 05:07:19.000000000 -0400
@@ -334,11 +334,7 @@ _dl_start_user:\n\
 	 add r0,r12\n\
 	.align 2\n\
 1:	.long _GLOBAL_OFFSET_TABLE_\n\
-2:	! Store the highest stack address\n\
-	mov.l .L_stack_end,r0\n\
-	mov.l @(r0,r12),r0\n\
-	mov.l r15,@r0\n\
-	! See if we were run as a command with the executable file\n\
+2:	! See if we were run as a command with the executable file\n\
 	! name as an extra leading argument.\n\
 	mov.l .L_dl_skip_args,r0\n\
 	mov.l @(r0,r12),r0\n\
@@ -381,8 +377,6 @@ _dl_start_user:\n\
 	.align 2\n\
 .L_dl_start:\n\
 	.long _dl_start@PLT\n\
-.L_stack_end:\n\
-	.long __libc_stack_end@GOT\n\
 .L_dl_skip_args:\n\
 	.long _dl_skip_args@GOT\n\
 .L_dl_init:\n\
--- libc/sysdeps/sparc/sparc32/dl-machine.h.jj	2003-08-26 17:07:46.000000000 -0400
+++ libc/sysdeps/sparc/sparc32/dl-machine.h	2003-09-24 05:11:04.000000000 -0400
@@ -248,6 +248,11 @@ elf_machine_runtime_setup (struct link_m
 /* The SPARC overlaps DT_RELA and DT_PLTREL.  */
 #define ELF_MACHINE_PLTREL_OVERLAP 1
 
+/* Undo the sub %sp, 6*4, %sp; add %sp, 22*4, %o0 below to get at the
+   value we want in __libc_stack_end.  */
+#define DL_STACK_END(cookie) \
+  ((void *) (((long) (cookie)) - (22 - 6) * 4))
+
 /* Initial entry point code for the dynamic linker.
    The C function `_dl_start' is the real entry point;
    its return value is the user program's entry point.  */
@@ -274,16 +279,10 @@ _dl_start_user:\n\
 	add	%l7, %o7, %l7\n\
   /* Save the user entry point address in %l0 */\n\
 	mov	%o0, %l0\n\
-  /* Store the highest stack address.  */\n\
-	sethi	%hi(__libc_stack_end), %g2\n\
-	or	%g2, %lo(__libc_stack_end), %g2\n\
-	ld	[%l7 + %g2], %l1\n\
-	sethi	%hi(_dl_skip_args), %g2\n\
-	add	%sp, 6*4, %l2\n\
-	or	%g2, %lo(_dl_skip_args), %g2\n\
-	st	%l2, [%l1]\n\
   /* See if we were run as a command with the executable file name as an\n\
      extra leading argument.  If so, adjust the contents of the stack.  */\n\
+	sethi	%hi(_dl_skip_args), %g2\n\
+	or	%g2, %lo(_dl_skip_args), %g2\n\
 	ld	[%l7+%g2], %i0\n\
 	ld	[%i0], %i0\n\
 	tst	%i0\n\
--- libc/sysdeps/sparc/sparc64/dl-machine.h.jj	2003-07-31 04:36:02.000000000 -0400
+++ libc/sysdeps/sparc/sparc64/dl-machine.h	2003-09-24 05:14:58.000000000 -0400
@@ -666,6 +666,11 @@ elf_machine_runtime_setup (struct link_m
 /* The PLT uses Elf64_Rela relocs.  */
 #define elf_machine_relplt elf_machine_rela
 
+/* Undo the sub %sp, 6*8, %sp; add %sp, STACK_BIAS + 22*8, %o0 below
+   to get at the value we want in __libc_stack_end.  */
+#define DL_STACK_END(cookie) \
+  ((void *) (((long) (cookie)) - (22 - 6) * 8 - STACK_BIAS))
+
 /* Initial entry point code for the dynamic linker.
    The C function `_dl_start' is the real entry point;
    its return value is the user program's entry point.  */
@@ -694,20 +699,14 @@ elf_machine_runtime_setup (struct link_m
 "1:	call	11f\n"							\
 "	 sethi	%hi(_GLOBAL_OFFSET_TABLE_-(1b-.)), %l7\n"		\
 "11:	or	%l7, %lo(_GLOBAL_OFFSET_TABLE_-(1b-.)), %l7\n"		\
-"  /* Store the highest stack address.  */\n"				\
-"	sethi	%hi(__libc_stack_end), %g5\n"				\
+"	sethi	%hi(_dl_skip_args), %g5\n"				\
 "	add	%l7, %o7, %l7\n"					\
-"	or	%g5, %lo(__libc_stack_end), %g5\n"			\
+"	or	%g5, %lo(_dl_skip_args), %g5\n"				\
 "   /* Save the user entry point address in %l0.  */\n"			\
 "	mov	%o0, %l0\n"						\
-"	ldx	[%l7 + %g5], %l1\n"					\
-"	sethi	%hi(_dl_skip_args), %g5\n"				\
-"	add	%sp, 6*8, %l2\n"					\
 "   /* See if we were run as a command with the executable file name as an\n" \
 "      extra leading argument.  If so, we must shift things around since we\n" \
 "      must keep the stack doubleword aligned.  */\n"			\
-"	or	%g5, %lo(_dl_skip_args), %g5\n"				\
-"	stx	%l2, [%l1]\n"						\
 "	ldx	[%l7 + %g5], %i0\n"					\
 "	ld	[%i0], %i0\n"						\
 "	brz,pt	%i0, 2f\n"						\
--- libc/sysdeps/x86_64/dl-machine.h.jj	2003-09-24 04:20:43.000000000 -0400
+++ libc/sysdeps/x86_64/dl-machine.h	2003-09-24 05:16:28.000000000 -0400
@@ -260,8 +260,6 @@ _dl_runtime_profile:\n\
 .globl _start\n\
 .globl _dl_start_user\n\
 _start:\n\
-	# Store the highest stack address\n\
-	movq %rsp, __libc_stack_end(%rip)\n\
 	movq %rsp, %rdi\n\
 	call _dl_start\n\
 _dl_start_user:\n\

	Jakub