/* Copyright (C) 2004, 2005 Free Software Foundation. Ensure builtin __snprintf_chk performs correctly. */ 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 sprintf (char *, const char *, ...); extern int snprintf (char *, size_t, const char *, ...); #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. */ void __attribute__((noinline)) test1 (void) { chk_calls = 0; /* snprintf_disallowed = 1; */ memset (buffer, 'A', 32); snprintf (buffer, 4, "foo"); if (memcmp (buffer, "foo", 4) || buffer[4] != 'A') abort (); memset (buffer, 'A', 32); if (snprintf (buffer, 4, "foo bar") != 7) abort (); if (memcmp (buffer, "foo", 4) || buffer[4] != 'A') abort (); memset (buffer, 'A', 32); snprintf (buffer, 32, "%s", "bar"); if (memcmp (buffer, "bar", 4) || buffer[4] != 'A') abort (); memset (buffer, 'A', 32); if (snprintf (buffer, 21, "%s", "bar") != 3) abort (); if (memcmp (buffer, "bar", 4) || buffer[4] != 'A') abort (); snprintf_disallowed = 0; memset (buffer, 'A', 32); if (snprintf (buffer, 4, "%d%d%d", (int) l1, (int) l1 + 1, (int) l1 + 12) != 4) abort (); if (memcmp (buffer, "121", 4) || buffer[4] != 'A') abort (); memset (buffer, 'A', 32); if (snprintf (buffer, 32, "%d%d%d", (int) l1, (int) l1 + 1, (int) l1 + 12) != 4) abort (); if (memcmp (buffer, "1213", 5) || buffer[5] != 'A') abort (); if (chk_calls) abort (); memset (buffer, 'A', 32); snprintf (buffer, strlen (ptr) + 1, "%s", ptr); if (memcmp (buffer, "barf", 5) || buffer[5] != 'A') abort (); memset (buffer, 'A', 32); snprintf (buffer, l1 + 31, "%d - %c", (int) l1 + 27, *ptr); if (memcmp (buffer, "28 - b\0AAAAA", 12)) abort (); if (chk_calls != 2) abort (); chk_calls = 0; memset (s4, 'A', 32); snprintf (s4, l1 + 6, "%d - %c", (int) l1 - 17, ptr[1]); if (memcmp (s4, "-16 - \0AAA", 10)) abort (); if (chk_calls) abort (); } /* Test whether compile time checking is done where it should and so is runtime object size checking. */ void __attribute__((noinline)) test2 (void) { struct A { char buf1[10]; char buf2[10]; } a; char *r = l1 == 1 ? &a.buf1[5] : &a.buf2[4]; char buf3[20]; int i; /* The following calls should do runtime checking - length is not known, but destination is. */ chk_calls = 0; snprintf (a.buf1 + 2, l1, "%s", s3 + 3); snprintf (r, l1 + 4, "%s%c", s3 + 3, s3[3]); r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7]; snprintf (r, strlen (s2) - 2, "%c %s", s2[2], s2 + 4); snprintf (r + 2, l1, s3 + 3); r = buf3; for (i = 0; i < 4; ++i) { if (i == l1 - 1) r = &a.buf1[1]; else if (i == l1) r = &a.buf2[7]; else if (i == l1 + 1) r = &buf3[5]; else if (i == l1 + 2) r = &a.buf1[9]; } snprintf (r, l1, s2 + 4); if (chk_calls != 5) abort (); /* Following have known destination and known source length, so if optimizing certainly shouldn't result in the checking variants. */ chk_calls = 0; /* snprintf_disallowed = 1; */ snprintf (a.buf1 + 2, 4, ""); snprintf (r, 1, "a"); r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7]; snprintf (r, 3, "%s", s1 + 1); r = buf3; for (i = 0; i < 4; ++i) { if (i == l1 - 1) r = &a.buf1[1]; else if (i == l1) r = &a.buf2[7]; else if (i == l1 + 1) r = &buf3[5]; else if (i == l1 + 2) r = &a.buf1[9]; } snprintf (r, 1, "%s", ""); snprintf (r, 0, "%s", ""); snprintf_disallowed = 0; /* Unknown destination and source, no checking. */ snprintf (s4, l1 + 31, "%s %d", s3, 0); if (chk_calls) abort (); } /* Test whether runtime and/or compile time checking catches buffer overflows. */ void __attribute__((noinline)) test3 (void) { struct A { char buf1[10]; char buf2[10]; } a; char buf3[20]; chk_fail_allowed = 1; /* Runtime checks. */ if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&a.buf2[9], l1 + 1, "%c%s", s2[3], s2 + 4); abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&a.buf2[7], l1 + 30, "%s%c", s3 + strlen (s3) - 2, *s3); abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&a.buf2[7], l1 + 3, "%d", (int) l1 + 9999); abort (); } /* This should be detectable at compile time already. */ if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&buf3[19], 2, "a"); abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&buf3[17], 4, "a"); abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { snprintf (&buf3[17], 4, "%s", "abc"); 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 (); }