From be9240c84c67de44959905a829141576965a0588 Mon Sep 17 00:00:00 2001 From: Fangrui Song Date: Tue, 19 Apr 2022 15:52:27 -0700 Subject: [PATCH] elf: Remove __libc_init_secure After 73fc4e28b9464f0e13edc719a5372839970e7ddb, __libc_enable_secure_decided is always 0 and a statically linked executable may overwrite __libc_enable_secure without considering AT_SECURE. The __libc_enable_secure has been correctly initialized in _dl_aux_init, so just remove __libc_enable_secure_decided and __libc_init_secure. This allows us to remove some startup_get*id functions from 22b79ed7f413cd980a7af0cf258da5bf82b6d5e5. Reviewed-by: Florian Weimer (cherry picked from commit 3e9acce8c50883b6cd8a3fb653363d9fa21e1608) --- csu/libc-start.c | 3 --- elf/enbl-secure.c | 10 --------- include/libc-internal.h | 3 --- include/unistd.h | 1 - sysdeps/generic/startup.h | 24 --------------------- sysdeps/mach/hurd/enbl-secure.c | 30 -------------------------- sysdeps/mach/hurd/i386/init-first.c | 4 ---- sysdeps/unix/sysv/linux/i386/startup.h | 24 --------------------- 8 files changed, 99 deletions(-) delete mode 100644 sysdeps/mach/hurd/enbl-secure.c diff --git a/csu/libc-start.c b/csu/libc-start.c index d01e57ea59..a2fc2f6f96 100644 --- a/csu/libc-start.c +++ b/csu/libc-start.c @@ -285,9 +285,6 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL), } } - /* Initialize very early so that tunables can use it. */ - __libc_init_secure (); - __tunables_init (__environ); ARCH_INIT_CPU_FEATURES (); diff --git a/elf/enbl-secure.c b/elf/enbl-secure.c index 9e47526bd3..1208610bd0 100644 --- a/elf/enbl-secure.c +++ b/elf/enbl-secure.c @@ -26,15 +26,5 @@ #include #include -/* If nonzero __libc_enable_secure is already set. */ -int __libc_enable_secure_decided; /* Safest assumption, if somehow the initializer isn't run. */ int __libc_enable_secure = 1; - -void -__libc_init_secure (void) -{ - if (__libc_enable_secure_decided == 0) - __libc_enable_secure = (startup_geteuid () != startup_getuid () - || startup_getegid () != startup_getgid ()); -} diff --git a/include/libc-internal.h b/include/libc-internal.h index 749dfb919c..44fcb6bdf8 100644 --- a/include/libc-internal.h +++ b/include/libc-internal.h @@ -21,9 +21,6 @@ #include -/* Initialize the `__libc_enable_secure' flag. */ -extern void __libc_init_secure (void); - /* Discover the tick frequency of the machine if something goes wrong, we return 0, an impossible hertz. */ extern int __profile_frequency (void); diff --git a/include/unistd.h b/include/unistd.h index 7849562c42..5824485629 100644 --- a/include/unistd.h +++ b/include/unistd.h @@ -180,7 +180,6 @@ libc_hidden_proto (__sbrk) and some functions contained in the C library ignore various environment variables that normally affect them. */ extern int __libc_enable_secure attribute_relro; -extern int __libc_enable_secure_decided; rtld_hidden_proto (__libc_enable_secure) diff --git a/sysdeps/generic/startup.h b/sysdeps/generic/startup.h index 04f20cde47..c3be5430bd 100644 --- a/sysdeps/generic/startup.h +++ b/sysdeps/generic/startup.h @@ -23,27 +23,3 @@ /* Use macro instead of inline function to avoid including . */ #define _startup_fatal(message) __libc_fatal ((message)) - -static inline uid_t -startup_getuid (void) -{ - return __getuid (); -} - -static inline uid_t -startup_geteuid (void) -{ - return __geteuid (); -} - -static inline gid_t -startup_getgid (void) -{ - return __getgid (); -} - -static inline gid_t -startup_getegid (void) -{ - return __getegid (); -} diff --git a/sysdeps/mach/hurd/enbl-secure.c b/sysdeps/mach/hurd/enbl-secure.c deleted file mode 100644 index 3e9a6b888d..0000000000 --- a/sysdeps/mach/hurd/enbl-secure.c +++ /dev/null @@ -1,30 +0,0 @@ -/* Define and initialize the `__libc_enable_secure' flag. Hurd version. - Copyright (C) 1998-2021 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 - . */ - -/* There is no need for this file in the Hurd; it is just a placeholder - to prevent inclusion of the sysdeps/generic version. - In the shared library, the `__libc_enable_secure' variable is defined - by the dynamic linker in dl-sysdep.c and set there. - In the static library, it is defined in init-first.c and set there. */ - -#include - -void -__libc_init_secure (void) -{ -} diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c index a430aae085..4dc9017ec8 100644 --- a/sysdeps/mach/hurd/i386/init-first.c +++ b/sysdeps/mach/hurd/i386/init-first.c @@ -38,10 +38,6 @@ extern void __init_misc (int, char **, char **); unsigned long int __hurd_threadvar_stack_offset; unsigned long int __hurd_threadvar_stack_mask; -#ifndef SHARED -int __libc_enable_secure; -#endif - extern int __libc_argc attribute_hidden; extern char **__libc_argv attribute_hidden; extern char **_dl_argv; diff --git a/sysdeps/unix/sysv/linux/i386/startup.h b/sysdeps/unix/sysv/linux/i386/startup.h index dee7a4f1d3..192c765361 100644 --- a/sysdeps/unix/sysv/linux/i386/startup.h +++ b/sysdeps/unix/sysv/linux/i386/startup.h @@ -32,30 +32,6 @@ _startup_fatal (const char *message __attribute__ ((unused))) ABORT_INSTRUCTION; __builtin_unreachable (); } - -static inline uid_t -startup_getuid (void) -{ - return (uid_t) INTERNAL_SYSCALL_CALL (getuid32); -} - -static inline uid_t -startup_geteuid (void) -{ - return (uid_t) INTERNAL_SYSCALL_CALL (geteuid32); -} - -static inline gid_t -startup_getgid (void) -{ - return (gid_t) INTERNAL_SYSCALL_CALL (getgid32); -} - -static inline gid_t -startup_getegid (void) -{ - return (gid_t) INTERNAL_SYSCALL_CALL (getegid32); -} #else # include_next #endif