/* Copyright (C) 2004, 2005, 2011 Free Software Foundation. Ensure builtin __stpncpy_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 *stpncpy (char *, const char *, size_t); extern int memcmp (const void *, const void *, size_t); extern int strcmp (const char *, const char *); extern int strncmp (const char *, const char *, size_t); extern void *memset (void *, int, size_t); #include "chk.h" const char s1[] = "123"; char p[32] = ""; char * volatile s2 = "defg"; /* prevent constant propagation to happen when whole program assumptions are made. */ char * volatile s3 = "FGH"; /* prevent constant propagation to happen when whole program assumptions are made. */ char *s4; volatile size_t l1 = 1; /* prevent constant propagation to happen when whole program assumptions are made. */ int i; void __attribute__((noinline)) test1 (void) { const char *const src = "hello world"; const char *src2; char dst[64], *dst2; chk_calls = 0; memset (dst, 0, sizeof (dst)); if (stpncpy (dst, src, 4) != dst+4 || strncmp (dst, src, 4)) abort(); memset (dst, 0, sizeof (dst)); if (stpncpy (dst+16, src, 4) != dst+20 || strncmp (dst+16, src, 4)) abort(); memset (dst, 0, sizeof (dst)); if (stpncpy (dst+32, src+5, 4) != dst+36 || strncmp (dst+32, src+5, 4)) abort(); memset (dst, 0, sizeof (dst)); dst2 = dst; if (stpncpy (++dst2, src+5, 4) != dst+5 || strncmp (dst2, src+5, 4) || dst2 != dst+1) abort(); memset (dst, 0, sizeof (dst)); if (stpncpy (dst, src, 0) != dst || strcmp (dst, "")) abort(); memset (dst, 0, sizeof (dst)); dst2 = dst; src2 = src; if (stpncpy (++dst2, ++src2, 0) != dst+1 || strcmp (dst2, "") || dst2 != dst+1 || src2 != src+1) abort(); memset (dst, 0, sizeof (dst)); dst2 = dst; src2 = src; if (stpncpy (++dst2+5, ++src2+5, 0) != dst+6 || strcmp (dst2+5, "") || dst2 != dst+1 || src2 != src+1) abort(); memset (dst, 0, sizeof (dst)); if (stpncpy (dst, src, 12) != dst+11 || strcmp (dst, src)) abort(); /* Test at least one instance of the __builtin_ style. We do this to ensure that it works and that the prototype is correct. */ memset (dst, 0, sizeof (dst)); if (__builtin_stpncpy (dst, src, 4) != dst+4 || strncmp (dst, src, 4)) abort(); memset (dst, 0, sizeof (dst)); if (stpncpy (dst, i++ ? "xfoo" + 1 : "bar", 4) != dst+3 || strcmp (dst, "bar") || i != 1) abort (); /* If return value of stpncpy is ignored, it should be optimized into stpncpy call. */ stpncpy_disallowed = 1; stpncpy (dst + 1, src, 4); stpncpy_disallowed = 0; if (strncmp (dst + 1, src, 4)) abort (); if (chk_calls) abort (); } void __attribute__((noinline)) test2 (void) { chk_calls = 0; /* No runtime checking should be done here, both destination and length are unknown. */ size_t cpy_length = l1 < 4 ? l1 + 1 : 4; if (stpncpy (s4, "abcd", l1 + 1) != s4 + cpy_length || strncmp (s4, "abcd", cpy_length)) 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)) test3 (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; const char *l; size_t l2; /* The following calls should do runtime checking - source length is not known, but destination is. The returned value is checked so that stpncpy calls are not rewritten to strncpy calls. */ chk_calls = 0; if (!stpncpy (a.buf1 + 2, s3 + 3, l1)) abort(); if (!stpncpy (r, s3 + 2, l1 + 2)) abort(); r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7]; if (!stpncpy (r, s2 + 2, l1 + 2)) abort(); if (!stpncpy (r + 2, s3 + 3, l1)) abort(); 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]; } if (!stpncpy (r, s2 + 4, l1)) abort(); if (chk_calls != 5) abort (); /* Following have known destination and known length, so if optimizing certainly shouldn't result in the checking variants. */ chk_calls = 0; if (!stpncpy (a.buf1 + 2, "", 3)) abort (); if (!stpncpy (a.buf1 + 2, "", 0)) abort (); if (!stpncpy (r, "a", 1)) abort (); if (!stpncpy (r, "a", 3)) abort (); r = l1 == 1 ? __builtin_alloca (4) : &a.buf2[7]; if (!stpncpy (r, s1 + 1, 3)) abort (); if (!stpncpy (r, s1 + 1, 2)) abort (); r = buf3; l = "abc"; l2 = 4; for (i = 0; i < 4; ++i) { if (i == l1 - 1) r = &a.buf1[1], l = "e", l2 = 2; else if (i == l1) r = &a.buf2[7], l = "gh", l2 = 3; else if (i == l1 + 1) r = &buf3[5], l = "jkl", l2 = 4; else if (i == l1 + 2) r = &a.buf1[9], l = "", l2 = 1; } if (!stpncpy (r, "", 1)) abort (); /* Here, strlen (l) + 1 is known to be at most 4 and __builtin_object_size (&buf3[16], 0) is 4, so this doesn't need runtime checking. */ if (!stpncpy (&buf3[16], l, l2)) abort (); if (!stpncpy (&buf3[15], "abc", l2)) abort (); if (!stpncpy (&buf3[10], "fghij", l2)) abort (); if (chk_calls) abort (); chk_calls = 0; } /* Test whether runtime and/or compile time checking catches buffer overflows. */ void __attribute__((noinline)) test4 (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) { if (stpncpy (&a.buf2[9], s2 + 4, l1 + 1)) // returned value used to prevent stpncpy calls // to be rewritten in strncpy calls i++; abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { if (stpncpy (&a.buf2[7], s3, l1 + 4)) i++; abort (); } /* This should be detectable at compile time already. */ if (__builtin_setjmp (chk_fail_buf) == 0) { if (stpncpy (&buf3[19], "abc", 2)) i++; abort (); } if (__builtin_setjmp (chk_fail_buf) == 0) { if (stpncpy (&buf3[18], "", 3)) i++; 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)); test1 (); s4 = p; test2 (); test3 (); test4 (); }