From 88f4b6929c26f9240a4b0b7dcc62922f02544a09 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Tue, 18 Oct 2022 17:00:07 +0200 Subject: Introduce , extracted from This allows us to define a generic no-op version of PTR_MANGLE and PTR_DEMANGLE. In the future, we can use PTR_MANGLE and PTR_DEMANGLE unconditionally in C sources, avoiding an unintended loss of hardening due to missing include files or unlucky header inclusion ordering. In i386 and x86_64, we can avoid a dependency in the C code by using the computed constant from . no longer includes these definitions, so there is no cyclic dependency anymore when computing the constants. Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/sh/____longjmp_chk.S | 1 + sysdeps/unix/sysv/linux/sh/pointer_guard.h | 43 ++++++++++++++++++++++++++++ sysdeps/unix/sysv/linux/sh/sysdep.h | 19 ------------ 3 files changed, 44 insertions(+), 19 deletions(-) create mode 100644 sysdeps/unix/sysv/linux/sh/pointer_guard.h (limited to 'sysdeps/unix/sysv/linux/sh') diff --git a/sysdeps/unix/sysv/linux/sh/____longjmp_chk.S b/sysdeps/unix/sysv/linux/sh/____longjmp_chk.S index e821e158c4..cf69926316 100644 --- a/sysdeps/unix/sysv/linux/sh/____longjmp_chk.S +++ b/sysdeps/unix/sysv/linux/sh/____longjmp_chk.S @@ -16,6 +16,7 @@ . */ #include +#include #include diff --git a/sysdeps/unix/sysv/linux/sh/pointer_guard.h b/sysdeps/unix/sysv/linux/sh/pointer_guard.h new file mode 100644 index 0000000000..32a571d496 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sh/pointer_guard.h @@ -0,0 +1,43 @@ +/* Pointer obfuscation implenentation. Generic (no-op) version. + Copyright (C) 2005-2022 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 + . */ + +#ifndef POINTER_GUARD_H +#define POINTER_GUARD_H + +#if IS_IN (rtld) +/* We cannot use the thread descriptor because in ld.so we use setjmp + earlier than the descriptor is initialized. Using a global variable + is too complicated here since we have no PC-relative addressing mode. */ +# include +#else +# ifdef __ASSEMBLER__ +# define PTR_MANGLE(reg, tmp) \ + stc gbr,tmp; mov.l @(POINTER_GUARD,tmp),tmp; xor tmp,reg +# define PTR_MANGLE2(reg, tmp) xor tmp,reg +# define PTR_DEMANGLE(reg, tmp) PTR_MANGLE (reg, tmp) +# define PTR_DEMANGLE2(reg, tmp) PTR_MANGLE2 (reg, tmp) +# else +# include +# include +# define PTR_MANGLE(var) \ + (var) = (void *) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ()) +# define PTR_DEMANGLE(var) PTR_MANGLE (var) +# endif +#endif + +#endif /* POINTER_GUARD_H */ diff --git a/sysdeps/unix/sysv/linux/sh/sysdep.h b/sysdeps/unix/sysv/linux/sh/sysdep.h index e9e13cd184..a2f43f68c3 100644 --- a/sysdeps/unix/sysv/linux/sh/sysdep.h +++ b/sysdeps/unix/sysv/linux/sh/sysdep.h @@ -315,23 +315,4 @@ #endif /* __ASSEMBLER__ */ -/* Pointer mangling support. */ -#if IS_IN (rtld) -/* We cannot use the thread descriptor because in ld.so we use setjmp - earlier than the descriptor is initialized. Using a global variable - is too complicated here since we have no PC-relative addressing mode. */ -#else -# ifdef __ASSEMBLER__ -# define PTR_MANGLE(reg, tmp) \ - stc gbr,tmp; mov.l @(POINTER_GUARD,tmp),tmp; xor tmp,reg -# define PTR_MANGLE2(reg, tmp) xor tmp,reg -# define PTR_DEMANGLE(reg, tmp) PTR_MANGLE (reg, tmp) -# define PTR_DEMANGLE2(reg, tmp) PTR_MANGLE2 (reg, tmp) -# else -# define PTR_MANGLE(var) \ - (var) = (void *) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ()) -# define PTR_DEMANGLE(var) PTR_MANGLE (var) -# endif -#endif - #endif /* linux/sh/sysdep.h */ -- cgit 1.4.1