From 7e631fb024651c1aa645d2565a19c03356c83400 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sun, 6 May 2018 05:16:07 -0700
Subject: [PATCH] Mark _init and _fini as hidden [BZ #23145]
_init and _fini are special functions provided by glibc for linker to
define DT_INIT and DT_FINI in executable and shared library. They
should never be put in dynamic symbol table. This patch marks them as
hidden to remove them from dynamic symbol table.
Tested with build-many-glibcs.py.
[BZ #23145]
* elf/Makefile (tests-special): Add $(objpfx)check-initfini.out.
($(all-built-dso:=.dynsym): New target.
(common-generated): Add $(all-built-dso:$(common-objpfx)%=%.dynsym).
($(objpfx)check-initfini.out): New target.
(generated): Add check-initfini.out.
* scripts/check-initfini.awk: New file.
* sysdeps/aarch64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/alpha/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/arm/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/hppa/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/i386/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/ia64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/m68k/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/microblaze/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips64/n32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/mips/mips64/n64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/nios2/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/powerpc/powerpc32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/powerpc/powerpc64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/s390/s390-32/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/s390/s390-64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/sh/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/sparc/crti.S (_init): Mark as hidden.
(_fini): Likewise.
* sysdeps/x86_64/crti.S (_init): Mark as hidden.
(_fini): Likewise.
---
elf/Makefile | 15 +++++++-
scripts/check-initfini.awk | 63 ++++++++++++++++++++++++++++++++
sysdeps/aarch64/crti.S | 2 +
sysdeps/alpha/crti.S | 2 +
sysdeps/arm/crti.S | 2 +
sysdeps/hppa/crti.S | 2 +
sysdeps/i386/crti.S | 2 +
sysdeps/ia64/crti.S | 2 +
sysdeps/m68k/crti.S | 2 +
sysdeps/microblaze/crti.S | 2 +
sysdeps/mips/mips32/crti.S | 2 +
sysdeps/mips/mips64/n32/crti.S | 2 +
sysdeps/mips/mips64/n64/crti.S | 2 +
sysdeps/nios2/crti.S | 2 +
sysdeps/powerpc/powerpc32/crti.S | 2 +
sysdeps/powerpc/powerpc64/crti.S | 2 +
sysdeps/s390/s390-32/crti.S | 2 +
sysdeps/s390/s390-64/crti.S | 2 +
sysdeps/sh/crti.S | 2 +
sysdeps/sparc/crti.S | 2 +
sysdeps/x86_64/crti.S | 2 +
21 files changed, 115 insertions(+), 1 deletion(-)
create mode 100644 scripts/check-initfini.awk
@@ -348,7 +348,7 @@ ifeq ($(run-built-tests),yes)
tests-special += $(objpfx)tst-pathopt.out $(objpfx)tst-rtld-load-self.out
endif
tests-special += $(objpfx)check-textrel.out $(objpfx)check-execstack.out \
- $(objpfx)check-localplt.out
+ $(objpfx)check-localplt.out $(objpfx)check-initfini.out
endif
ifeq ($(run-built-tests),yes)
@@ -1136,6 +1136,19 @@ $(objpfx)check-localplt.out: $(..)scripts/check-localplt.awk \
$(evaluate-test)
endif
+$(all-built-dso:=.dynsym): %.dynsym: %
+ @rm -f $@T
+ LC_ALL=C $(READELF) -W --dyn-syms $< > $@T
+ test -s $@T
+ mv -f $@T $@
+common-generated += $(all-built-dso:$(common-objpfx)%=%.dynsym)
+
+$(objpfx)check-initfini.out: $(..)scripts/check-initfini.awk \
+ $(all-built-dso:=.dynsym)
+ LC_ALL=C $(AWK) -f $^ > $@; \
+ $(evaluate-test)
+generated += check-initfini.out
+
$(objpfx)tst-dlopenrpathmod.so: $(libdl)
$(objpfx)tst-dlopenrpath: $(objpfx)tst-dlopenrpathmod.so $(libdl)
CFLAGS-tst-dlopenrpath.c += -DPFX=\"$(objpfx)\"
new file mode 100644
@@ -0,0 +1,63 @@
+# Copyright (C) 2018 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+
+# You should have received a copy of the GNU Lesser General Public
+# License along with the GNU C Library; if not, see
+# <http://www.gnu.org/licenses/>.
+
+# This awk script expects to get command-line files that are each
+# the output of 'readelf -W --dyn-syms' on a single shared object.
+# It exits successfully (0) if none contained _init nor _fini in dynamic
+# symbol table.
+# It fails (1) if any did contain _init or _fini in dynamic symbol table.
+# It fails (2) if the input did not take the expected form.
+
+BEGIN { result = _init = _fini = sanity = 0 }
+
+function check_one(name) {
+ if (!sanity) {
+ print name ": *** input did not look like readelf -d output";
+ result = 2;
+ } else {
+ ok = 1;
+ if (_init) {
+ print name ": *** _init is in dynamic symbol table";
+ result = result ? result : 1;
+ ok = 0;
+ }
+ if (_fini) {
+ print name ": *** _fini is in dynamic symbol table";
+ result = result ? result : 1;
+ ok = 0;
+ }
+ if (ok)
+ print name ": OK";
+ }
+
+ _init = _fini = sanity = 0
+}
+
+FILENAME != lastfile {
+ if (lastfile)
+ check_one(lastfile);
+ lastfile = FILENAME;
+}
+
+$1 == "Symbol" && $2 == "table" && $3 == "'.dynsym'" { sanity = 1 }
+$8 == "_init" { _init = 1 }
+$8 == "_fini" { _fini = 1 }
+
+END {
+ check_one(lastfile);
+ exit(result);
+}
@@ -72,6 +72,7 @@ call_weak_fn:
.section .init,"ax",%progbits
.align 2
.global _init
+ .hidden _init
.type _init, %function
_init:
stp x29, x30, [sp, -16]!
@@ -85,6 +86,7 @@ _init:
.section .fini,"ax",%progbits
.align 2
.global _fini
+ .hidden _fini
.type _fini, %function
_fini:
stp x29, x30, [sp, -16]!
@@ -67,6 +67,7 @@
.section .init, "ax", @progbits
.globl _init
+ .hidden _init
.type _init, @function
.usepv _init, std
_init:
@@ -89,6 +90,7 @@ _init:
.section .fini, "ax", @progbits
.globl _fini
+ .hidden _fini
.type _fini,@function
.usepv _fini,std
_fini:
@@ -78,6 +78,7 @@ call_weak_fn:
.section .init,"ax",%progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, %function
_init:
push {r3, lr}
@@ -90,6 +91,7 @@ _init:
.section .fini,"ax",%progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, %function
_fini:
push {r3, lr}
@@ -142,6 +142,7 @@ gmon_initializer:
.section .init, "ax", %progbits
.align 4
.globl _init
+ .hidden _init
.type _init,@function
_init:
stw %rp,-20(%sp)
@@ -152,6 +153,7 @@ _init:
.section .fini,"ax",%progbits
.align 4
.globl _fini
+ .hidden _fini
.type _fini,@function
_fini:
stw %rp,-20(%sp)
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
pushl %ebx
@@ -77,6 +78,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
pushl %ebx
@@ -129,6 +129,7 @@ gmon_initializer:
.section .init,"ax",@progbits
.global _init#
+ .hidden _init#
.proc _init#
_init:
.prologue
@@ -145,6 +146,7 @@ _init:
.section .fini,"ax",@progbits
.global _fini#
+ .hidden _fini#
.proc _fini#
_fini:
.prologue
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
link.w %fp, #0
@@ -75,6 +76,7 @@ _init:
.section .fini,"ax",@progbits
.align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
link.w %fp, #0
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
addik r1,r1,-32
@@ -79,6 +80,7 @@ $Lno_weak_fn:
.section .fini,"ax",@progbits
.align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
addik r1,r1,-32
@@ -65,6 +65,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
.set noreorder
@@ -90,6 +91,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
.set noreorder
@@ -65,6 +65,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
addiu $sp,$sp,-16
@@ -90,6 +91,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
addiu $sp,$sp,-16
@@ -65,6 +65,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
daddiu $sp,$sp,-16
@@ -90,6 +91,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
daddiu $sp,$sp,-16
@@ -57,6 +57,7 @@
.section .init,"ax",@progbits
.align 2
.global _init
+ .hidden _init
.type _init, @function
_init:
addi sp, sp, -8
@@ -84,6 +85,7 @@ _init:
.section .fini,"ax",@progbits
.align 2
.global _fini
+ .hidden _fini
.type _fini, @function
_fini:
addi sp, sp, -8
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
stwu r1, -16(r1)
@@ -80,6 +81,7 @@ _init:
.section .fini,"ax",@progbits
.align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
stwu r1, -16(r1)
@@ -62,6 +62,7 @@
#endif
.section ".init", "ax", @progbits
ENTRY_2(_init)
+ .hidden _init
.align ALIGNARG (2)
BODY_LABEL (_init):
LOCALENTRY(_init)
@@ -80,6 +81,7 @@ BODY_LABEL (_init):
.section ".fini", "ax", @progbits
ENTRY_2(_fini)
+ .hidden _fini
.align ALIGNARG (2)
BODY_LABEL (_fini):
LOCALENTRY(_fini)
@@ -57,6 +57,7 @@
.section .init,"ax",@progbits
.globl _init
+ .hidden _init
.type _init,@function
.align 4
_init:
@@ -88,6 +89,7 @@ _init:
.section .fini,"ax",@progbits
.globl _fini
+ .hidden _fini
.type _fini,@function
.align 4
_fini:
@@ -59,6 +59,7 @@
.section .init,"ax",@progbits
.align 4
.globl _init
+ .hidden _init
.type _init,@function
_init:
stmg %r6,%r15,48(%r15)
@@ -81,6 +82,7 @@ _init:
.section .fini,"ax",@progbits
.align 4
.globl _fini
+ .hidden _fini
.type _fini,@function
_fini:
stmg %r6,%r15,48(%r15)
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.align 5
.global _init
+ .hidden _init
.type _init, @function
_init:
mov.l r12,@-r15
@@ -103,6 +104,7 @@ _init:
.section .fini,"ax",@progbits
.align 5
.global _fini
+ .hidden _fini
.type _fini, @function
_fini:
mov.l r12,@-r15
@@ -66,6 +66,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
save %sp, -STACKFRAME_SIZE, %sp
@@ -88,6 +89,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
save %sp, -STACKFRAME_SIZE, %sp
@@ -58,6 +58,7 @@
.section .init,"ax",@progbits
.p2align 2
.globl _init
+ .hidden _init
.type _init, @function
_init:
/* Maintain 16-byte stack alignment for called functions. */
@@ -75,6 +76,7 @@ _init:
.section .fini,"ax",@progbits
.p2align 2
.globl _fini
+ .hidden _fini
.type _fini, @function
_fini:
subq $8, %rsp
--
2.17.0