diff options
Diffstat (limited to 'sys-libs/glibc/files/2.25/glibc-2.25-gentoo-chk_fail.c')
| -rw-r--r-- | sys-libs/glibc/files/2.25/glibc-2.25-gentoo-chk_fail.c | 303 |
1 files changed, 303 insertions, 0 deletions
diff --git a/sys-libs/glibc/files/2.25/glibc-2.25-gentoo-chk_fail.c b/sys-libs/glibc/files/2.25/glibc-2.25-gentoo-chk_fail.c new file mode 100644 index 0000000..2ef96b7 --- /dev/null +++ b/sys-libs/glibc/files/2.25/glibc-2.25-gentoo-chk_fail.c @@ -0,0 +1,303 @@ +/* Copyright (C) 2004-2014 Free Software Foundation, Inc. + Copyright (C) 2006-2014 Gentoo 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* Hardened Gentoo SSP and FORTIFY handler + + A failure handler that does not use functions from the rest of glibc; + it uses the INTERNAL_SYSCALL methods directly. This helps ensure no + possibility of recursion into the handler. + + Direct all bug reports to http://bugs.gentoo.org/ + + People who have contributed significantly to the evolution of this file: + Ned Ludd - <solar[@]gentoo.org> + Alexander Gabert - <pappy[@]gentoo.org> + The PaX Team - <pageexec[@]freemail.hu> + Peter S. Mazinger - <ps.m[@]gmx.net> + Yoann Vandoorselaere - <yoann[@]prelude-ids.org> + Robert Connolly - <robert[@]linuxfromscratch.org> + Cory Visi <cory[@]visi.name> + Mike Frysinger <vapier[@]gentoo.org> + Magnus Granberg <zorry[@]gentoo.org> + Kevin F. Quinn - <kevquinn[@]gentoo.org> + */ + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <signal.h> + +#include <sys/types.h> + +#include <sysdep-cancel.h> +#include <sys/syscall.h> + +#include <kernel-features.h> + +#include <alloca.h> +/* from sysdeps */ +#include <socketcall.h> +/* for the stuff in bits/socket.h */ +#include <sys/socket.h> +#include <sys/un.h> + +/* Sanity check on SYSCALL macro names - force compilation + * failure if the names used here do not exist + */ +#if !defined __NR_socketcall && !defined __NR_socket +# error Cannot do syscall socket or socketcall +#endif +#if !defined __NR_socketcall && !defined __NR_connect +# error Cannot do syscall connect or socketcall +#endif +#ifndef __NR_write +# error Cannot do syscall write +#endif +#ifndef __NR_close +# error Cannot do syscall close +#endif +#ifndef __NR_getpid +# error Cannot do syscall getpid +#endif +#ifndef __NR_kill +# error Cannot do syscall kill +#endif +#ifndef __NR_exit +# error Cannot do syscall exit +#endif +#ifdef SSP_SMASH_DUMPS_CORE +# define ENABLE_SSP_SMASH_DUMPS_CORE 1 +# if !defined _KERNEL_NSIG && !defined _NSIG +# error No _NSIG or _KERNEL_NSIG for rt_sigaction +# endif +# if !defined __NR_sigaction && !defined __NR_rt_sigaction +# error Cannot do syscall sigaction or rt_sigaction +# endif +/* Although rt_sigaction expects sizeof(sigset_t) - it expects the size + * of the _kernel_ sigset_t which is not the same as the user sigset_t. + * Most arches have this as _NSIG bits - mips has _KERNEL_NSIG bits for + * some reason. + */ +# ifdef _KERNEL_NSIG +# define _SSP_NSIG _KERNEL_NSIG +# else +# define _SSP_NSIG _NSIG +# endif +#else +# define _SSP_NSIG 0 +# define ENABLE_SSP_SMASH_DUMPS_CORE 0 +#endif + +/* Define DO_SIGACTION - default to newer rt signal interface but + * fallback to old as needed. + */ +#ifdef __NR_rt_sigaction +# define DO_SIGACTION(signum, act, oldact) \ + INLINE_SYSCALL(rt_sigaction, 4, signum, act, oldact, _SSP_NSIG/8) +#else +# define DO_SIGACTION(signum, act, oldact) \ + INLINE_SYSCALL(sigaction, 3, signum, act, oldact) +#endif + +/* Define DO_SOCKET/DO_CONNECT functions to deal with socketcall vs socket/connect */ +#if defined(__NR_socket) && defined(__NR_connect) +# define USE_OLD_SOCKETCALL 0 +#else +# define USE_OLD_SOCKETCALL 1 +#endif + +/* stub out the __NR_'s so we can let gcc optimize away dead code */ +#ifndef __NR_socketcall +# define __NR_socketcall 0 +#endif +#ifndef __NR_socket +# define __NR_socket 0 +#endif +#ifndef __NR_connect +# define __NR_connect 0 +#endif +#define DO_SOCKET(result, domain, type, protocol) \ + do { \ + if (USE_OLD_SOCKETCALL) { \ + socketargs[0] = domain; \ + socketargs[1] = type; \ + socketargs[2] = protocol; \ + socketargs[3] = 0; \ + result = INLINE_SYSCALL(socketcall, 2, SOCKOP_socket, socketargs); \ + } else \ + result = INLINE_SYSCALL(socket, 3, domain, type, protocol); \ + } while (0) +#define DO_CONNECT(result, sockfd, serv_addr, addrlen) \ + do { \ + if (USE_OLD_SOCKETCALL) { \ + socketargs[0] = sockfd; \ + socketargs[1] = (unsigned long int)serv_addr; \ + socketargs[2] = addrlen; \ + socketargs[3] = 0; \ + result = INLINE_SYSCALL(socketcall, 2, SOCKOP_connect, socketargs); \ + } else \ + result = INLINE_SYSCALL(connect, 3, sockfd, serv_addr, addrlen); \ + } while (0) + +#ifndef _PATH_LOG +# define _PATH_LOG "/dev/log" +#endif + +static const char path_log[] = _PATH_LOG; + +/* For building glibc with SSP switched on, define __progname to a + * constant if building for the run-time loader, to avoid pulling + * in more of libc.so into ld.so + */ +#ifdef IS_IN_rtld +static const char *__progname = "<ldso>"; +#else +extern const char *__progname; +#endif + +#ifdef GENTOO_SSP_HANDLER +# define ERROR_MSG "stack smashing" +#else +# define ERROR_MSG "buffer overflow" +#endif + +/* Common handler code, used by chk_fail + * Inlined to ensure no self-references to the handler within itself. + * Data static to avoid putting more than necessary on the stack, + * to aid core debugging. + */ +__attribute__ ((__noreturn__, __always_inline__)) +static inline void +__hardened_gentoo_fail(void) +{ +#define MESSAGE_BUFSIZ 512 + static pid_t pid; + static int plen, i, hlen; + static char message[MESSAGE_BUFSIZ]; + /* <11> is LOG_USER|LOG_ERR. A dummy date for loggers to skip over. */ + static const char msg_header[] = "<11>" __DATE__ " " __TIME__ " glibc-gentoo-hardened-check: "; + static const char msg_ssd[] = "*** " ERROR_MSG " detected ***: "; + static const char msg_terminated[] = " terminated; "; + static const char msg_report[] = "report to " REPORT_BUGS_TO "\n"; + static const char msg_unknown[] = "<unknown>"; + static int log_socket, connect_result; + static struct sockaddr_un sock; + static unsigned long int socketargs[4]; + + /* Build socket address */ + sock.sun_family = AF_UNIX; + i = 0; + while (path_log[i] != '\0' && i < sizeof(sock.sun_path) - 1) { + sock.sun_path[i] = path_log[i]; + ++i; + } + sock.sun_path[i] = '\0'; + + /* Try SOCK_DGRAM connection to syslog */ + connect_result = -1; + DO_SOCKET(log_socket, AF_UNIX, SOCK_DGRAM, 0); + if (log_socket != -1) + DO_CONNECT(connect_result, log_socket, &sock, sizeof(sock)); + if (connect_result == -1) { + if (log_socket != -1) + INLINE_SYSCALL(close, 1, log_socket); + /* Try SOCK_STREAM connection to syslog */ + DO_SOCKET(log_socket, AF_UNIX, SOCK_STREAM, 0); + if (log_socket != -1) + DO_CONNECT(connect_result, log_socket, &sock, sizeof(sock)); + } + + /* Build message. Messages are generated both in the old style and new style, + * so that log watchers that are configured for the old-style message continue + * to work. + */ +#define strconcat(str) \ + ({ \ + i = 0; \ + while ((str[i] != '\0') && ((i + plen) < (MESSAGE_BUFSIZ - 1))) { \ + message[plen + i] = str[i]; \ + ++i; \ + } \ + plen += i; \ + }) + + /* Tersely log the failure */ + plen = 0; + strconcat(msg_header); + hlen = plen; + strconcat(msg_ssd); + if (__progname != NULL) + strconcat(__progname); + else + strconcat(msg_unknown); + strconcat(msg_terminated); + strconcat(msg_report); + + /* Write out error message to STDERR, to syslog if open */ + INLINE_SYSCALL(write, 3, STDERR_FILENO, message + hlen, plen - hlen); + if (connect_result != -1) { + INLINE_SYSCALL(write, 3, log_socket, message, plen); + INLINE_SYSCALL(close, 1, log_socket); + } + + /* Time to kill self since we have no idea what is going on */ + pid = INLINE_SYSCALL(getpid, 0); + + if (ENABLE_SSP_SMASH_DUMPS_CORE) { + /* Remove any user-supplied handler for SIGABRT, before using it. */ +#if 0 + /* + * Note: Disabled because some programs catch & process their + * own crashes. We've already enabled this code path which + * means we want to let core dumps happen. + */ + static struct sigaction default_abort_act; + default_abort_act.sa_handler = SIG_DFL; + default_abort_act.sa_sigaction = NULL; + __sigfillset(&default_abort_act.sa_mask); + default_abort_act.sa_flags = 0; + if (DO_SIGACTION(SIGABRT, &default_abort_act, NULL) == 0) +#endif + INLINE_SYSCALL(kill, 2, pid, SIGABRT); + } + + /* SIGKILL is only signal which cannot be caught */ + INLINE_SYSCALL(kill, 2, pid, SIGKILL); + + /* In case the kill didn't work, exit anyway. + * The loop prevents gcc thinking this routine returns. + */ + while (1) + INLINE_SYSCALL(exit, 1, 137); +} + +__attribute__ ((__noreturn__)) +#ifdef GENTOO_SSP_HANDLER +void __stack_chk_fail(void) +#else +void __chk_fail(void) +#endif +{ + __hardened_gentoo_fail(); +} + +#ifdef GENTOO_SSP_HANDLER +strong_alias (__stack_chk_fail, __stack_chk_fail_local) +#endif |