mirror of
https://github.com/coreutils/coreutils.git
synced 2024-11-28 12:35:36 +08:00
.
This commit is contained in:
Jim Meyering
parent
66937ee56b
commit
0a72ec6c46
435
lib/c-stack.c
435
lib/c-stack.c
@ -1,435 +0,0 @@
|
|||||||
/* Stack overflow handling.
|
|
||||||
|
|
||||||
Copyright (C) 2002 Free Software Foundation, Inc.
|
|
||||||
|
|
||||||
This program is free software; you can redistribute it and/or modify
|
|
||||||
it under the terms of the GNU General Public License as published by
|
|
||||||
the Free Software Foundation; either version 2, or (at your option)
|
|
||||||
any later version.
|
|
||||||
|
|
||||||
This program 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 General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU General Public License
|
|
||||||
along with this program; if not, write to the Free Software Foundation,
|
|
||||||
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
|
|
||||||
|
|
||||||
/* Written by Paul Eggert. */
|
|
||||||
|
|
||||||
/* NOTES:
|
|
||||||
|
|
||||||
A program that uses alloca, dynamic arrays, or large local
|
|
||||||
variables may extend the stack by more than a page at a time. If
|
|
||||||
so, when the stack overflows the operating system may not detect
|
|
||||||
the overflow until the program uses the array, and this module may
|
|
||||||
incorrectly report a program error instead of a stack overflow.
|
|
||||||
|
|
||||||
To avoid this problem, allocate only small objects on the stack; a
|
|
||||||
program should be OK if it limits single allocations to a page or
|
|
||||||
less. Allocate larger arrays in static storage, or on the heap
|
|
||||||
(e.g., with malloc). Yes, this is a pain, but we don't know of any
|
|
||||||
better solution that is portable.
|
|
||||||
|
|
||||||
No attempt has been made to deal with multithreaded applications.
|
|
||||||
|
|
||||||
If ! HAVE_XSI_STACK_OVERFLOW_HEURISTIC, the current implementation
|
|
||||||
assumes that, if the RLIMIT_STACK limit changes during execution,
|
|
||||||
then c_stack_action is invoked immediately afterwards. */
|
|
||||||
|
|
||||||
#if HAVE_CONFIG_H
|
|
||||||
# include <config.h>
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#ifndef __attribute__
|
|
||||||
# if __GNUC__ < 3 || __STRICT_ANSI__
|
|
||||||
# define __attribute__(x)
|
|
||||||
# endif
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#include "gettext.h"
|
|
||||||
#define _(msgid) gettext (msgid)
|
|
||||||
|
|
||||||
#include <errno.h>
|
|
||||||
#ifndef ENOTSUP
|
|
||||||
# define ENOTSUP EINVAL
|
|
||||||
#endif
|
|
||||||
#ifndef EOVERFLOW
|
|
||||||
# define EOVERFLOW EINVAL
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#include <signal.h>
|
|
||||||
#if ! HAVE_STACK_T && ! defined stack_t
|
|
||||||
typedef struct sigaltstack stack_t;
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#include <stdlib.h>
|
|
||||||
#include <string.h>
|
|
||||||
|
|
||||||
#if HAVE_SYS_RESOURCE_H
|
|
||||||
/* Include sys/time.h here, because...
|
|
||||||
SunOS-4.1.x <sys/resource.h> fails to include <sys/time.h>.
|
|
||||||
This gives "incomplete type" errors for ru_utime and tu_stime. */
|
|
||||||
# if HAVE_SYS_TIME_H
|
|
||||||
# include <sys/time.h>
|
|
||||||
# endif
|
|
||||||
# include <sys/resource.h>
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#if HAVE_UCONTEXT_H
|
|
||||||
# include <ucontext.h>
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#if HAVE_UNISTD_H
|
|
||||||
# include <unistd.h>
|
|
||||||
#endif
|
|
||||||
#ifndef STDERR_FILENO
|
|
||||||
# define STDERR_FILENO 2
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#if DEBUG
|
|
||||||
# include <stdio.h>
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#include "c-stack.h"
|
|
||||||
#include "exitfail.h"
|
|
||||||
|
|
||||||
extern char *program_name;
|
|
||||||
|
|
||||||
/* The user-specified action to take when a SEGV-related program error
|
|
||||||
or stack overflow occurs. */
|
|
||||||
static void (* volatile segv_action) (int);
|
|
||||||
|
|
||||||
/* Translated messages for program errors and stack overflow. Do not
|
|
||||||
translate them in the signal handler, since gettext is not
|
|
||||||
async-signal-safe. */
|
|
||||||
static char const * volatile program_error_message;
|
|
||||||
static char const * volatile stack_overflow_message;
|
|
||||||
|
|
||||||
/* Output an error message, then exit with status EXIT_FAILURE if it
|
|
||||||
appears to have been a stack overflow, or with a core dump
|
|
||||||
otherwise. This function is async-signal-safe. */
|
|
||||||
|
|
||||||
static void die (int) __attribute__ ((noreturn));
|
|
||||||
static void
|
|
||||||
die (int signo)
|
|
||||||
{
|
|
||||||
char const *message =
|
|
||||||
signo ? program_error_message : stack_overflow_message;
|
|
||||||
segv_action (signo);
|
|
||||||
write (STDERR_FILENO, program_name, strlen (program_name));
|
|
||||||
write (STDERR_FILENO, ": ", 2);
|
|
||||||
write (STDERR_FILENO, message, strlen (message));
|
|
||||||
write (STDERR_FILENO, "\n", 1);
|
|
||||||
if (! signo)
|
|
||||||
_exit (exit_failure);
|
|
||||||
kill (getpid (), signo);
|
|
||||||
abort ();
|
|
||||||
}
|
|
||||||
|
|
||||||
#if HAVE_SIGALTSTACK && HAVE_DECL_SIGALTSTACK
|
|
||||||
|
|
||||||
/* Direction of the C runtime stack. This function is
|
|
||||||
async-signal-safe. */
|
|
||||||
|
|
||||||
# if STACK_DIRECTION
|
|
||||||
# define find_stack_direction(ptr) STACK_DIRECTION
|
|
||||||
# else
|
|
||||||
static int
|
|
||||||
find_stack_direction (char const *addr)
|
|
||||||
{
|
|
||||||
char dummy;
|
|
||||||
return ! addr ? find_stack_direction (&dummy) : addr < &dummy ? 1 : -1;
|
|
||||||
}
|
|
||||||
# endif
|
|
||||||
|
|
||||||
# if HAVE_XSI_STACK_OVERFLOW_HEURISTIC
|
|
||||||
# define get_stack_location(argv) 0
|
|
||||||
# else
|
|
||||||
|
|
||||||
# if defined RLIMIT_STACK && defined _SC_PAGESIZE
|
|
||||||
|
|
||||||
/* Return the minimum machine address deducible from ARGV. This
|
|
||||||
includes the addresses of all the strings that ARGV points at, as
|
|
||||||
well as the address of ARGV itself. */
|
|
||||||
|
|
||||||
static char const *
|
|
||||||
min_address_from_argv (char * const *argv)
|
|
||||||
{
|
|
||||||
char const *min = (char const *) argv;
|
|
||||||
char const *p;
|
|
||||||
while ((p = *argv++))
|
|
||||||
if (p < min)
|
|
||||||
min = p;
|
|
||||||
return min;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Return the maximum machine address deducible from ARGV. */
|
|
||||||
|
|
||||||
static char const *
|
|
||||||
max_address_from_argv (char * const *argv)
|
|
||||||
{
|
|
||||||
char const *max = *argv;
|
|
||||||
char const *max1;
|
|
||||||
char const *p;
|
|
||||||
while ((p = *argv++))
|
|
||||||
if (max < p)
|
|
||||||
max = p;
|
|
||||||
max1 = (char const *) (argv + 1);
|
|
||||||
return max && max1 < max ? max + strlen (max) + 1 : max1;
|
|
||||||
}
|
|
||||||
# endif
|
|
||||||
|
|
||||||
/* The base and size of the stack, determined at startup. */
|
|
||||||
static char const * volatile stack_base;
|
|
||||||
static size_t volatile stack_size;
|
|
||||||
|
|
||||||
/* Store the base and size of the stack into the static variables
|
|
||||||
STACK_BASE and STACK_SIZE. The base is the numerically lowest
|
|
||||||
address in the stack. Return -1 (setting errno) if this cannot be
|
|
||||||
done. */
|
|
||||||
|
|
||||||
static int
|
|
||||||
get_stack_location (char * const *argv)
|
|
||||||
{
|
|
||||||
# if ! (defined RLIMIT_STACK && defined _SC_PAGESIZE)
|
|
||||||
|
|
||||||
errno = ENOTSUP;
|
|
||||||
return -1;
|
|
||||||
|
|
||||||
# else
|
|
||||||
|
|
||||||
struct rlimit rlimit;
|
|
||||||
int r = getrlimit (RLIMIT_STACK, &rlimit);
|
|
||||||
if (r == 0)
|
|
||||||
{
|
|
||||||
char const *base;
|
|
||||||
size_t size = rlimit.rlim_cur;
|
|
||||||
extern char **environ;
|
|
||||||
size_t page_size = sysconf (_SC_PAGESIZE);
|
|
||||||
int stack_direction = find_stack_direction (0);
|
|
||||||
|
|
||||||
# if HAVE_GETCONTEXT && HAVE_DECL_GETCONTEXT
|
|
||||||
ucontext_t context;
|
|
||||||
if (getcontext (&context) == 0)
|
|
||||||
{
|
|
||||||
base = context.uc_stack.ss_sp;
|
|
||||||
if (stack_direction < 0)
|
|
||||||
base -= size - context.uc_stack.ss_size;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
# endif
|
|
||||||
{
|
|
||||||
if (stack_direction < 0)
|
|
||||||
{
|
|
||||||
char const *a = max_address_from_argv (argv);
|
|
||||||
char const *b = max_address_from_argv (environ);
|
|
||||||
base = (a < b ? b : a) - size;
|
|
||||||
base += - (size_t) base % page_size;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
char const *a = min_address_from_argv (argv);
|
|
||||||
char const *b = min_address_from_argv (environ);
|
|
||||||
base = a < b ? a : b;
|
|
||||||
base -= (size_t) base % page_size;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
if (size != rlimit.rlim_cur
|
|
||||||
|| rlimit.rlim_cur < 0
|
|
||||||
|| base + size < base
|
|
||||||
# ifdef RLIM_SAVED_CUR
|
|
||||||
|| rlimit.rlim_cur == RLIM_SAVED_CUR
|
|
||||||
# endif
|
|
||||||
# ifdef RLIM_SAVED_MAX
|
|
||||||
|| rlimit.rlim_cur == RLIM_SAVED_MAX
|
|
||||||
# endif
|
|
||||||
# ifdef RLIM_INFINITY
|
|
||||||
|| rlimit.rlim_cur == RLIM_INFINITY
|
|
||||||
# endif
|
|
||||||
)
|
|
||||||
{
|
|
||||||
errno = EOVERFLOW;
|
|
||||||
return -1;
|
|
||||||
}
|
|
||||||
|
|
||||||
stack_base = base;
|
|
||||||
stack_size = size;
|
|
||||||
|
|
||||||
# if DEBUG
|
|
||||||
fprintf (stderr, "get_stack_location base=%p size=%lx\n",
|
|
||||||
base, (unsigned long) size);
|
|
||||||
# endif
|
|
||||||
}
|
|
||||||
|
|
||||||
return r;
|
|
||||||
|
|
||||||
# endif
|
|
||||||
}
|
|
||||||
# endif
|
|
||||||
|
|
||||||
/* Storage for the alternate signal stack. */
|
|
||||||
static union
|
|
||||||
{
|
|
||||||
char buffer[SIGSTKSZ];
|
|
||||||
|
|
||||||
/* These other members are for proper alignment. There's no
|
|
||||||
standard way to guarantee stack alignment, but this seems enough
|
|
||||||
in practice. */
|
|
||||||
long double ld;
|
|
||||||
long l;
|
|
||||||
void *p;
|
|
||||||
} alternate_signal_stack;
|
|
||||||
|
|
||||||
# if defined SA_ONSTACK && defined SA_SIGINFO && defined _SC_PAGESIZE
|
|
||||||
|
|
||||||
/* Handle a segmentation violation and exit. This function is
|
|
||||||
async-signal-safe. */
|
|
||||||
|
|
||||||
static void segv_handler (int, siginfo_t *, void *) __attribute__((noreturn));
|
|
||||||
static void
|
|
||||||
segv_handler (int signo, siginfo_t *info,
|
|
||||||
void *context __attribute__ ((unused)))
|
|
||||||
{
|
|
||||||
/* Clear SIGNO if it seems to have been a stack overflow. */
|
|
||||||
if (0 < info->si_code)
|
|
||||||
{
|
|
||||||
/* If the faulting address is within the stack, or within one
|
|
||||||
page of the stack end, assume that it is a stack
|
|
||||||
overflow. */
|
|
||||||
# if HAVE_XSI_STACK_OVERFLOW_HEURISTIC
|
|
||||||
ucontext_t const *user_context = context;
|
|
||||||
char const *stack_base = user_context->uc_stack.ss_sp;
|
|
||||||
size_t stack_size = user_context->uc_stack.ss_size;
|
|
||||||
# endif
|
|
||||||
char const *faulting_address = info->si_addr;
|
|
||||||
size_t s = faulting_address - stack_base;
|
|
||||||
size_t page_size = sysconf (_SC_PAGESIZE);
|
|
||||||
if (find_stack_direction (0) < 0)
|
|
||||||
s += page_size;
|
|
||||||
if (s < stack_size + page_size)
|
|
||||||
signo = 0;
|
|
||||||
|
|
||||||
# if DEBUG
|
|
||||||
{
|
|
||||||
char buf[1024];
|
|
||||||
sprintf (buf,
|
|
||||||
"segv_handler fault=%p base=%p size=%lx page=%lx signo=%d\n",
|
|
||||||
faulting_address, stack_base, (unsigned long) stack_size,
|
|
||||||
(unsigned long) page_size, signo);
|
|
||||||
write (STDERR_FILENO, buf, strlen (buf));
|
|
||||||
}
|
|
||||||
# endif
|
|
||||||
}
|
|
||||||
|
|
||||||
die (signo);
|
|
||||||
}
|
|
||||||
# endif
|
|
||||||
|
|
||||||
static void
|
|
||||||
null_action (int signo __attribute__ ((unused)))
|
|
||||||
{
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Assuming ARGV is the argument vector of `main', set up ACTION so
|
|
||||||
that it is invoked on C stack overflow. Return -1 (setting errno)
|
|
||||||
if this cannot be done.
|
|
||||||
|
|
||||||
When ACTION is called, it is passed an argument equal to SIGSEGV
|
|
||||||
for a segmentation violation that does not appear related to stack
|
|
||||||
overflow, and is passed zero otherwise.
|
|
||||||
|
|
||||||
A null ACTION acts like an action that does nothing.
|
|
||||||
|
|
||||||
ACTION must be async-signal-safe. ACTION together with its callees
|
|
||||||
must not require more than SIGSTKSZ bytes of stack space. */
|
|
||||||
|
|
||||||
int
|
|
||||||
c_stack_action (char * const *argv __attribute__ ((unused)),
|
|
||||||
void (*action) (int))
|
|
||||||
{
|
|
||||||
int r = get_stack_location (argv);
|
|
||||||
if (r != 0)
|
|
||||||
return r;
|
|
||||||
|
|
||||||
{
|
|
||||||
stack_t st;
|
|
||||||
st.ss_flags = 0;
|
|
||||||
st.ss_sp = alternate_signal_stack.buffer;
|
|
||||||
st.ss_size = sizeof alternate_signal_stack.buffer;
|
|
||||||
r = sigaltstack (&st, 0);
|
|
||||||
if (r != 0)
|
|
||||||
return r;
|
|
||||||
}
|
|
||||||
|
|
||||||
segv_action = action ? action : null_action;
|
|
||||||
program_error_message = _("program error");
|
|
||||||
stack_overflow_message = _("stack overflow");
|
|
||||||
|
|
||||||
{
|
|
||||||
# if ! (defined SA_ONSTACK && defined SA_SIGINFO && defined _SC_PAGESIZE)
|
|
||||||
return signal (SIGSEGV, die) == SIG_ERR ? -1 : 0;
|
|
||||||
# else
|
|
||||||
struct sigaction act;
|
|
||||||
sigemptyset (&act.sa_mask);
|
|
||||||
|
|
||||||
/* POSIX 1003.1-2001 says SA_RESETHAND implies SA_NODEFER, but
|
|
||||||
this is not true on Solaris 8 at least. It doesn't hurt to use
|
|
||||||
SA_NODEFER here, so leave it in. */
|
|
||||||
act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND | SA_SIGINFO;
|
|
||||||
|
|
||||||
act.sa_sigaction = segv_handler;
|
|
||||||
|
|
||||||
return sigaction (SIGSEGV, &act, 0);
|
|
||||||
# endif
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
#else /* ! (HAVE_SIGALTSTACK && HAVE_DECL_SIGALTSTACK) */
|
|
||||||
|
|
||||||
int
|
|
||||||
c_stack_action (char * const *argv __attribute__ ((unused)),
|
|
||||||
void (*action) (int) __attribute__ ((unused)))
|
|
||||||
{
|
|
||||||
errno = ENOTSUP;
|
|
||||||
return -1;
|
|
||||||
}
|
|
||||||
|
|
||||||
#endif
|
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
#if DEBUG
|
|
||||||
|
|
||||||
int volatile exit_failure;
|
|
||||||
|
|
||||||
static long
|
|
||||||
recurse (char *p)
|
|
||||||
{
|
|
||||||
char array[500];
|
|
||||||
array[0] = 1;
|
|
||||||
return *p + recurse (array);
|
|
||||||
}
|
|
||||||
|
|
||||||
char *program_name;
|
|
||||||
|
|
||||||
int
|
|
||||||
main (int argc __attribute__ ((unused)), char **argv)
|
|
||||||
{
|
|
||||||
program_name = argv[0];
|
|
||||||
fprintf (stderr, "The last line of output should be \"stack overflow\".\n");
|
|
||||||
if (c_stack_action (argv, 0) == 0)
|
|
||||||
return recurse ("\1");
|
|
||||||
perror ("c_stack_action");
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
#endif /* DEBUG */
|
|
||||||
|
|
||||||
/*
|
|
||||||
Local Variables:
|
|
||||||
compile-command: "gcc -DDEBUG -DHAVE_CONFIG_H -I.. -g -O -Wall -W c-stack.c"
|
|
||||||
End:
|
|
||||||
*/
|
|
||||||
@ -1,19 +0,0 @@
|
|||||||
/* Stack overflow handling.
|
|
||||||
|
|
||||||
Copyright (C) 2002 Free Software Foundation, Inc.
|
|
||||||
|
|
||||||
This program is free software; you can redistribute it and/or modify
|
|
||||||
it under the terms of the GNU General Public License as published by
|
|
||||||
the Free Software Foundation; either version 2, or (at your option)
|
|
||||||
any later version.
|
|
||||||
|
|
||||||
This program 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 General Public License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU General Public License
|
|
||||||
along with this program; if not, write to the Free Software Foundation,
|
|
||||||
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
|
|
||||||
|
|
||||||
int c_stack_action (char * const *, void (*) (int));
|
|
||||||
Loading…
Reference in New Issue
Block a user