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re-enable function pointer table protection, this time make sure that

malloc.c gets the first mmap() call (since it depends on that, for its
sbrk(0) use). ok deraadt@
OPENBSD_3_2
dhartmei 22 years ago
parent
commit
cef62f0908
3 changed files with 92 additions and 71 deletions
  1. +51
    -35
      src/lib/libc/stdlib/atexit.c
  2. +26
    -30
      src/lib/libc/stdlib/atexit.h
  3. +15
    -6
      src/lib/libc/stdlib/exit.c

+ 51
- 35
src/lib/libc/stdlib/atexit.c View File

@ -1,46 +1,43 @@
/*-
* Copyright (c) 1990 The Regents of the University of California.
/*
* Copyright (c) 2002 Daniel Hartmeier
* All rights reserved. * All rights reserved.
* *
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without * Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions * modification, are permitted provided that the following conditions
* are met: * are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/ */
#if defined(LIBC_SCCS) && !defined(lint) #if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: atexit.c,v 1.4 2002/07/31 18:13:16 dhartmei Exp $";
static char *rcsid = "$OpenBSD: atexit.c,v 1.5 2002/08/30 07:58:07 dhartmei Exp $";
#endif /* LIBC_SCCS and not lint */ #endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/mman.h>
#include <stdlib.h> #include <stdlib.h>
#include "atexit.h" #include "atexit.h"
int __atexit_invalid = 1;
struct atexit *__atexit; struct atexit *__atexit;
/* /*
@ -50,18 +47,37 @@ int
atexit(fn) atexit(fn)
void (*fn)(); void (*fn)();
{ {
static struct atexit __atexit0; /* one guaranteed table */
register struct atexit *p;
register struct atexit *p = __atexit;
register int pgsize = getpagesize();
if ((p = __atexit) == NULL)
__atexit = p = &__atexit0;
else if (p->ind >= ATEXIT_SIZE) {
if ((p = malloc(sizeof(*p))) == NULL)
if (pgsize < sizeof(*p))
return (-1);
if (p != NULL) {
if (p->ind + 1 >= p->max)
p = NULL;
else if (mprotect(p, pgsize, PROT_READ | PROT_WRITE))
return (-1);
}
if (p == NULL) {
if (__atexit_invalid) {
/* malloc.c wants the first mmap() for sbrk()
games ('nice hack'), so enforce
malloc_init() with a dummy call. */
free(malloc(1));
__atexit_invalid = 0;
}
p = mmap(NULL, pgsize, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_PRIVATE, -1, 0);
if (p == MAP_FAILED)
return (-1); return (-1);
p->ind = 0; p->ind = 0;
p->max = (pgsize - ((char *)&p->fns[0] - (char *)p)) /
sizeof(p->fns[0]);
p->next = __atexit; p->next = __atexit;
__atexit = p; __atexit = p;
} }
p->fns[p->ind++] = fn; p->fns[p->ind++] = fn;
if (mprotect(p, pgsize, PROT_READ))
return (-1);
return (0); return (0);
} }

+ 26
- 30
src/lib/libc/stdlib/atexit.h View File

@ -1,45 +1,41 @@
/*-
* Copyright (c) 1990 The Regents of the University of California.
/* $OpenBSD: atexit.h,v 1.5 2002/08/30 07:58:07 dhartmei Exp $ */
/*
* Copyright (c) 2002 Daniel Hartmeier
* All rights reserved. * All rights reserved.
* *
* Redistribution and use in source and binary forms, with or without * Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions * modification, are permitted provided that the following conditions
* are met: * are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
* *
* $OpenBSD: atexit.h,v 1.4 2002/07/31 18:13:16 dhartmei Exp $
*/ */
/* must be at least 32 to guarantee ANSI conformance */
#define ATEXIT_SIZE 32
struct atexit { struct atexit {
struct atexit *next; /* next in list */ struct atexit *next; /* next in list */
int ind; /* next index in this table */ int ind; /* next index in this table */
void (*fns[ATEXIT_SIZE])(); /* the table itself */
int max; /* max entries >= ATEXIT_SIZE */
void (*fns[1])(); /* the table itself */
}; };
extern int __atexit_invalid;
extern struct atexit *__atexit; /* points to head of LIFO stack */ extern struct atexit *__atexit; /* points to head of LIFO stack */

+ 15
- 6
src/lib/libc/stdlib/exit.c View File

@ -32,9 +32,11 @@
*/ */
#if defined(LIBC_SCCS) && !defined(lint) #if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: exit.c,v 1.6 2002/07/31 18:13:16 dhartmei Exp $";
static char *rcsid = "$OpenBSD: exit.c,v 1.7 2002/08/30 07:58:07 dhartmei Exp $";
#endif /* LIBC_SCCS and not lint */ #endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/mman.h>
#include <stdlib.h> #include <stdlib.h>
#include <unistd.h> #include <unistd.h>
#include "atexit.h" #include "atexit.h"
@ -58,12 +60,19 @@ void
exit(status) exit(status)
int status; int status;
{ {
register struct atexit *p;
register int n;
register struct atexit *p, *q;
register int n, pgsize = getpagesize();
for (p = __atexit; p; p = p->next)
for (n = p->ind; --n >= 0;)
(*p->fns[n])();
if (!__atexit_invalid) {
p = __atexit;
while (p != NULL) {
for (n = p->ind; --n >= 0;)
(*p->fns[n])();
q = p;
p = p->next;
munmap(q, pgsize);
}
}
if (__cleanup) if (__cleanup)
(*__cleanup)(); (*__cleanup)();
_exit(status); _exit(status);


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