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/* Copyright (C) 2004, 2005 Free Software Foundation.
Ensure builtin __vsprintf_chk performs correctly. */
#include <stdarg.h>
extern void abort (void);
typedef __SIZE_TYPE__ size_t;
extern size_t strlen(const char *);
extern void *memcpy (void *, const void *, size_t);
extern char *strcpy (char *, const char *);
extern int memcmp (const void *, const void *, size_t);
extern void *memset (void *, int, size_t);
extern int vsprintf (char *, const char *, va_list);
#include "chk.h"
const char s1[] = "123";
char p[32] = "";
char *s2 = "defg";
char *s3 = "FGH";
char *s4;
size_t l1 = 1;
static char buffer[32];
char * volatile ptr = "barf"; /* prevent constant propagation to happen when whole program assumptions are made. */
int
__attribute__((noinline))
test1_sub (int i, ...)
{
int ret = 0;
va_list ap;
va_start (ap, i);
switch (i)
{
case 0:
vsprintf (buffer, "foo", ap);
break;
case 1:
ret = vsprintf (buffer, "foo", ap);
break;
case 2:
vsprintf (buffer, "%s", ap);
break;
case 3:
ret = vsprintf (buffer, "%s", ap);
break;
case 4:
vsprintf (buffer, "%d - %c", ap);
break;
case 5:
vsprintf (s4, "%d - %c", ap);
break;
}
va_end (ap);
return ret;
}
void
__attribute__((noinline))
test1 (void)
{
chk_calls = 0;
vsprintf_disallowed = 1;
memset (buffer, 'A', 32);
test1_sub (0);
if (memcmp (buffer, "foo", 4) || buffer[4] != 'A')
abort ();
memset (buffer, 'A', 32);
if (test1_sub (1) != 3)
abort ();
if (memcmp (buffer, "foo", 4) || buffer[4] != 'A')
abort ();
if (chk_calls)
abort ();
vsprintf_disallowed = 0;
memset (buffer, 'A', 32);
test1_sub (2, "bar");
if (memcmp (buffer, "bar", 4) || buffer[4] != 'A')
abort ();
memset (buffer, 'A', 32);
if (test1_sub (3, "bar") != 3)
abort ();
if (memcmp (buffer, "bar", 4) || buffer[4] != 'A')
abort ();
memset (buffer, 'A', 32);
test1_sub (2, ptr);
if (memcmp (buffer, "barf", 5) || buffer[5] != 'A')
abort ();
memset (buffer, 'A', 32);
test1_sub (4, (int) l1 + 27, *ptr);
if (memcmp (buffer, "28 - b\0AAAAA", 12))
abort ();
if (chk_calls != 4)
abort ();
chk_calls = 0;
test1_sub (5, (int) l1 - 17, ptr[1]);
if (memcmp (s4, "-16 - a", 8))
abort ();
if (chk_calls)
abort ();
}
void
__attribute__((noinline))
test2_sub (int i, ...)
{
va_list ap;
struct A { char buf1[10]; char buf2[10]; } a;
char *r = l1 == 1 ? &a.buf1[5] : &a.buf2[4];
char buf3[20];
int j;
va_start (ap, i);
/* The following calls should do runtime checking
- source length is not known, but destination is. */
switch (i)
{
case 0:
vsprintf (a.buf1 + 2, "%s", ap);
break;
case 1:
vsprintf (r, "%s%c", ap);
break;
case 2:
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
vsprintf (r, "%c %s", ap);
break;
case 3:
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
vsprintf (r + 2, s3 + 3, ap);
break;
case 4:
case 7:
r = buf3;
for (j = 0; j < 4; ++j)
{
if (j == l1 - 1)
r = &a.buf1[1];
else if (j == l1)
r = &a.buf2[7];
else if (j == l1 + 1)
r = &buf3[5];
else if (j == l1 + 2)
r = &a.buf1[9];
}
if (i == 4)
vsprintf (r, s2 + 4, ap);
else
vsprintf (r, "a", ap);
break;
case 5:
r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7];
vsprintf (r, "%s", ap);
break;
case 6:
vsprintf (a.buf1 + 2, "", ap);
break;
case 8:
vsprintf (s4, "%s %d", ap);
break;
}
va_end (ap);
}
/* Test whether compile time checking is done where it should
and so is runtime object size checking. */
void
__attribute__((noinline))
test2 (void)
{
/* The following calls should do runtime checking
- source length is not known, but destination is. */
chk_calls = 0;
test2_sub (0, s3 + 3);
test2_sub (1, s3 + 3, s3[3]);
test2_sub (2, s2[2], s2 + 4);
test2_sub (3);
test2_sub (4);
test2_sub (5, s1 + 1);
if (chk_calls != 6)
abort ();
/* Following have known destination and known source length,
so if optimizing certainly shouldn't result in the checking
variants. */
chk_calls = 0;
vsprintf_disallowed = 1;
test2_sub (6);
test2_sub (7);
vsprintf_disallowed = 0;
/* Unknown destination and source, no checking. */
test2_sub (8, s3, 0);
if (chk_calls)
abort ();
}
void
__attribute__((noinline))
test3_sub (int i, ...)
{
va_list ap;
struct A { char buf1[10]; char buf2[10]; } a;
char buf3[20];
va_start (ap, i);
/* The following calls should do runtime checking
- source length is not known, but destination is. */
switch (i)
{
case 0:
vsprintf (&a.buf2[9], "%c%s", ap);
break;
case 1:
vsprintf (&a.buf2[7], "%s%c", ap);
break;
case 2:
vsprintf (&a.buf2[7], "%d", ap);
break;
case 3:
vsprintf (&buf3[17], "%s", ap);
break;
case 4:
vsprintf (&buf3[19], "a", ap);
break;
}
va_end (ap);
}
/* Test whether runtime and/or compile time checking catches
buffer overflows. */
void
__attribute__((noinline))
test3 (void)
{
chk_fail_allowed = 1;
/* Runtime checks. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
test3_sub (0, s2[3], s2 + 4);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
test3_sub (1, s3 + strlen (s3) - 2, *s3);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
test3_sub (2, (int) l1 + 9999);
abort ();
}
if (__builtin_setjmp (chk_fail_buf) == 0)
{
test3_sub (3, "abc");
abort ();
}
/* This should be detectable at compile time already. */
if (__builtin_setjmp (chk_fail_buf) == 0)
{
test3_sub (4);
abort ();
}
chk_fail_allowed = 0;
}
void
main_test (void)
{
#ifndef __OPTIMIZE__
/* Object size checking is only intended for -O[s123]. */
return;
#endif
__asm ("" : "=r" (s2) : "0" (s2));
__asm ("" : "=r" (s3) : "0" (s3));
__asm ("" : "=r" (l1) : "0" (l1));
s4 = p;
test1 ();
test2 ();
test3 ();
}
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