1 /* Test and measure strcmp and wcscmp functions.
2    Copyright (C) 1999-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #define TEST_LEN (getpagesize () * 3)
20 #define MIN_PAGE_SIZE (TEST_LEN + 2 * getpagesize ())
21 
22 #define TEST_MAIN
23 #ifdef WIDE
24 # define TEST_NAME "wcscmp"
25 #else
26 # define TEST_NAME "strcmp"
27 #endif
28 #include "test-string.h"
29 #include <support/test-driver.h>
30 
31 #ifdef WIDE
32 # include <wchar.h>
33 
34 # define L(str) L##str
35 # define STRCMP wcscmp
36 # define STRCPY wcscpy
37 # define STRLEN wcslen
38 # define MEMCPY wmemcpy
39 # define SIMPLE_STRCMP simple_wcscmp
40 # define CHAR wchar_t
41 # define UCHAR wchar_t
42 # define CHARBYTES 4
43 # define CHARBYTESLOG 2
44 # define CHARALIGN __alignof__ (CHAR)
45 # define MIDCHAR 0x7fffffff
46 # define LARGECHAR 0xfffffffe
47 # define CHAR__MAX WCHAR_MAX
48 # define CHAR__MIN WCHAR_MIN
49 
50 /* Wcscmp uses signed semantics for comparison, not unsigned */
51 /* Avoid using substraction since possible overflow */
52 
53 int
simple_wcscmp(const wchar_t * s1,const wchar_t * s2)54 simple_wcscmp (const wchar_t *s1, const wchar_t *s2)
55 {
56   wchar_t c1, c2;
57   do
58     {
59       c1 = *s1++;
60       c2 = *s2++;
61       if (c2 == L'\0')
62       return c1 - c2;
63     }
64   while (c1 == c2);
65 
66   return c1 < c2 ? -1 : 1;
67 }
68 
69 #else
70 # include <limits.h>
71 
72 # define L(str) str
73 # define STRCMP strcmp
74 # define STRCPY strcpy
75 # define STRLEN strlen
76 # define MEMCPY memcpy
77 # define SIMPLE_STRCMP simple_strcmp
78 # define CHAR char
79 # define UCHAR unsigned char
80 # define CHARBYTES 1
81 # define CHARBYTESLOG 0
82 # define CHARALIGN 1
83 # define MIDCHAR 0x7f
84 # define LARGECHAR 0xfe
85 # define CHAR__MAX CHAR_MAX
86 # define CHAR__MIN CHAR_MIN
87 
88 /* Strcmp uses unsigned semantics for comparison. */
89 int
simple_strcmp(const char * s1,const char * s2)90 simple_strcmp (const char *s1, const char *s2)
91 {
92   int ret;
93 
94   while ((ret = *(unsigned char *) s1 - *(unsigned char*) s2++) == 0 && *s1++);
95   return ret;
96 }
97 
98 #endif
99 
100 typedef int (*proto_t) (const CHAR *, const CHAR *);
101 
102 IMPL (STRCMP, 1)
103 
104 static int
check_result(impl_t * impl,const CHAR * s1,const CHAR * s2,int exp_result)105 check_result (impl_t *impl,
106 	     const CHAR *s1, const CHAR *s2,
107 	     int exp_result)
108 {
109   int result = CALL (impl, s1, s2);
110   if ((exp_result == 0 && result != 0)
111       || (exp_result < 0 && result >= 0)
112       || (exp_result > 0 && result <= 0))
113     {
114       error (0, 0, "Wrong result in function %s %d %d", impl->name,
115 	     result, exp_result);
116       ret = 1;
117       return -1;
118     }
119 
120   return 0;
121 }
122 
123 static void
do_one_test(impl_t * impl,const CHAR * s1,const CHAR * s2,int exp_result)124 do_one_test (impl_t *impl,
125 	     const CHAR *s1, const CHAR *s2,
126 	     int exp_result)
127 {
128   if (check_result (impl, s1, s2, exp_result) < 0)
129     return;
130 }
131 
132 static void
do_test(size_t align1,size_t align2,size_t len,int max_char,int exp_result)133 do_test (size_t align1, size_t align2, size_t len, int max_char,
134          int exp_result)
135 {
136   size_t i;
137 
138   CHAR *s1, *s2;
139 
140   if (len == 0)
141     return;
142 
143   align1 &= ~(CHARBYTES - 1);
144   align2 &= ~(CHARBYTES - 1);
145 
146   align1 &= getpagesize () - 1;
147   if (align1 + (len + 1) * CHARBYTES >= page_size)
148     return;
149 
150   align2 &= getpagesize () - 1;
151   if (align2 + (len + 1) * CHARBYTES >= page_size)
152     return;
153 
154   /* Put them close to the end of page.  */
155   i = align1 + CHARBYTES * (len + 2);
156   s1 = (CHAR *)(buf1 + ((page_size - i) / 16 * 16) + align1);
157   i = align2 + CHARBYTES * (len + 2);
158   s2 = (CHAR *)(buf2 + ((page_size - i) / 16 * 16) + align2);
159 
160   for (i = 0; i < len; i++)
161     s1[i] = s2[i] = 1 + (23 << ((CHARBYTES - 1) * 8)) * i % max_char;
162 
163   s1[len] = s2[len] = 0;
164   s1[len + 1] = 23;
165   s2[len + 1] = 24 + exp_result;
166   s2[len - 1] -= exp_result;
167 
168   FOR_EACH_IMPL (impl, 0)
169   do_one_test (impl, s1, s2, exp_result);
170 }
171 
172 
173 static void
do_random_tests(void)174 do_random_tests (void)
175 {
176 	UCHAR *p1 = (UCHAR *) (buf1 + page_size - 512 * CHARBYTES);
177 	UCHAR *p2 = (UCHAR *) (buf2 + page_size - 512 * CHARBYTES);
178 
179 	for (size_t n = 0; n < ITERATIONS; n++)
180 	  {
181 	    /* for wcscmp case align1 and align2 mean here alignment
182 	       in wchar_t symbols, it equal 4*k alignment in bytes, we
183 	       don't check other alignments like for example
184 	       p1 = (wchar_t *)(buf1 + 1)
185 	       because it's wrong using of wchar_t type.  */
186 	    size_t align1 = random () & 31;
187 	    size_t align2;
188 	    if (random () & 1)
189 	      align2 = random () & 31;
190 	    else
191 	      align2 = align1 + (random () & 24);
192 	    size_t pos = random () & 511;
193 	    size_t j = align1 > align2 ? align1 : align2;
194 	    if (pos + j >= 511)
195 	      pos = 510 - j - (random () & 7);
196 	    size_t len1 = random () & 511;
197 	    if (pos >= len1 && (random () & 1))
198 	      len1 = pos + (random () & 7);
199 	    if (len1 + j >= 512)
200 	      len1 = 511 - j - (random () & 7);
201 	    size_t len2;
202 	    if (pos >= len1)
203 	      len2 = len1;
204 	    else
205 	      len2 = len1 + (len1 != 511 - j ? random () % (511 - j - len1) : 0);
206 	    j = (pos > len2 ? pos : len2) + align1 + 64;
207 	    if (j > 512)
208 	      j = 512;
209 	    for (size_t i = 0; i < j; ++i)
210 	      {
211 		p1[i] = random () & 255;
212 		if (i < len1 + align1 && !p1[i])
213 		  {
214 		    p1[i] = random () & 255;
215 		    if (!p1[i])
216 		      p1[i] = 1 + (random () & 127);
217 		  }
218 	      }
219 	    for (size_t i = 0; i < j; ++i)
220 	      {
221 		p2[i] = random () & 255;
222 		if (i < len2 + align2 && !p2[i])
223 		  {
224 		    p2[i] = random () & 255;
225 		    if (!p2[i])
226 		      p2[i] = 1 + (random () & 127);
227 		  }
228 	      }
229 
230 	    int result = 0;
231 	    MEMCPY (p2 + align2, p1 + align1, pos);
232 	    if (pos < len1)
233 	      {
234 		if (p2[align2 + pos] == p1[align1 + pos])
235 		  {
236 		    p2[align2 + pos] = random () & 255;
237 		    if (p2[align2 + pos] == p1[align1 + pos])
238 		      p2[align2 + pos] = p1[align1 + pos] + 3 + (random () & 127);
239 		  }
240 
241 		if (p1[align1 + pos] < p2[align2 + pos])
242 		  result = -1;
243 		else
244 		  result = 1;
245 	      }
246 	    p1[len1 + align1] = 0;
247 	    p2[len2 + align2] = 0;
248 
249 	    FOR_EACH_IMPL (impl, 1)
250 	      {
251 		int r = CALL (impl, (CHAR *) (p1 + align1), (CHAR *) (p2 + align2));
252 		/* Test whether on 64-bit architectures where ABI requires
253 		   callee to promote has the promotion been done.  */
254 		asm ("" : "=g" (r) : "0" (r));
255 		if ((r == 0 && result)
256 		    || (r < 0 && result >= 0)
257 		    || (r > 0 && result <= 0))
258 		  {
259 		    error (0, 0, "Iteration %zd - wrong result in function %s (align in bytes: %zd, align in bytes: %zd, len1:  %zd, len2: %zd, pos: %zd) %d != %d, p1 %p p2 %p",
260 			   n, impl->name, (size_t) (p1 + align1) & 63, (size_t) (p1 + align2) & 63, len1, len2, pos, r, result, p1, p2);
261 		    ret = 1;
262 		  }
263 	      }
264      }
265 }
266 
267 static void
check(void)268 check (void)
269 {
270   CHAR *s1 = (CHAR *) (buf1 + 0xb2c);
271   CHAR *s2 = (CHAR *) (buf1 + 0xfd8);
272 
273   STRCPY(s1, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrs"));
274   STRCPY(s2, L("abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkLMNOPQRSTUV"));
275 
276   /* Check correct working for negatives values */
277 
278   s1[0] = 1;
279   s2[0] = 1;
280   s1[1] = 1;
281   s2[1] = 1;
282   s1[2] = -1;
283   s2[2] = 3;
284   s1[3] = 0;
285   s2[3] = -1;
286 
287   /* Check possible overflow bug, actual more for wcscmp */
288 
289   s1[7] = CHAR__MIN;
290   s2[7] = CHAR__MAX;
291 
292   size_t l1 = STRLEN (s1);
293   size_t l2 = STRLEN (s2);
294 
295   for (size_t i1 = 0; i1 < l1; i1++)
296     for (size_t i2 = 0; i2 < l2; i2++)
297       {
298 		int exp_result = SIMPLE_STRCMP (s1 + i1, s2 + i2);
299 		FOR_EACH_IMPL (impl, 0)
300 		check_result (impl, s1 + i1, s2 + i2, exp_result);
301       }
302 
303   /* Test cases where there are multiple zero bytes after the first.  */
304 
305   for (size_t i = 0; i < 16 + 1; i++)
306     {
307       s1[i] = 0x00;
308       s2[i] = 0x00;
309     }
310 
311   for (size_t i = 0; i < 16; i++)
312     {
313       int exp_result;
314 
315       for (int val = 0x01; val < 0x100; val++)
316 	{
317 	  for (size_t j = 0; j < i; j++)
318 	    {
319 	      s1[j] = val;
320 	      s2[j] = val;
321 	    }
322 
323 	  s2[i] = val;
324 
325 	  exp_result = SIMPLE_STRCMP (s1, s2);
326 	  FOR_EACH_IMPL (impl, 0)
327 	    check_result (impl, s1, s2, exp_result);
328 	}
329     }
330 }
331 
332 static void
check2(void)333 check2 (void)
334 {
335   /* To trigger bug 25933, we need a size that is equal to the vector
336      length times 4. In the case of AVX2 for Intel, we need 32 * 4.  We
337      make this test generic and run it for all architectures as additional
338      boundary testing for such related algorithms.  */
339   size_t size = 32 * 4;
340   CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size);
341   CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size);
342   int exp_result;
343 
344   memset (s1, 'a', page_size);
345   memset (s2, 'a', page_size);
346   s1[(page_size / CHARBYTES) - 1] = (CHAR) 0;
347   s2[(page_size / CHARBYTES) - 1] = (CHAR) 0;
348 
349   /* Iterate over a size that is just below where we expect the bug to
350      trigger up to the size we expect will trigger the bug e.g. [99-128].
351      Likewise iterate the start of two strings between 30 and 31 bytes
352      away from the boundary to simulate alignment changes.  */
353   for (size_t s = 99; s <= size; s++)
354     for (size_t s1a = 30; s1a < 32; s1a++)
355       for (size_t s2a = 30; s2a < 32; s2a++)
356 	{
357 	  CHAR *s1p = s1 + (page_size / CHARBYTES - s) - s1a;
358 	  CHAR *s2p = s2 + (page_size / CHARBYTES - s) - s2a;
359 	  exp_result = SIMPLE_STRCMP (s1p, s2p);
360 	  FOR_EACH_IMPL (impl, 0)
361 	    check_result (impl, s1p, s2p, exp_result);
362 	}
363 }
364 
365 static void
check3(void)366 check3 (void)
367 {
368   size_t size = 0xd000 + 0x4000;
369   CHAR *s1, *s2;
370   CHAR *buffer1 = mmap (NULL, size, PROT_READ | PROT_WRITE,
371 			MAP_PRIVATE | MAP_ANON, -1, 0);
372   CHAR *buffer2 = mmap (NULL, size, PROT_READ | PROT_WRITE,
373 			MAP_PRIVATE | MAP_ANON, -1, 0);
374   if (buffer1 == MAP_FAILED || buffer1 == MAP_FAILED)
375     error (EXIT_UNSUPPORTED, errno, "mmap failed");
376 
377   s1 = (CHAR *) (buffer1 + 0x8f8 / sizeof (CHAR));
378   s2 = (CHAR *) (buffer2 + 0xcff3 / sizeof (CHAR));
379 
380   STRCPY(s1, L("/export/redhat/rpms/BUILD/java-1.8.0-openjdk-1.8.0.312.b07-2.fc35.x86_64/openjdk/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/util/PathDocFileFactory.java"));
381   STRCPY(s2, L("/export/redhat/rpms/BUILD/java-1.8.0-openjdk-1.8.0.312.b07-2.fc35.x86_64/openjdk/langtools/src/share/classes/com/sun/tools/doclets/internal/toolkit/taglets/ThrowsTaglet.java"));
382 
383   int exp_result = SIMPLE_STRCMP (s1, s2);
384   FOR_EACH_IMPL (impl, 0)
385     check_result (impl, s1, s2, exp_result);
386 
387   munmap ((void *) buffer1, size);
388   munmap ((void *) buffer2, size);
389 }
390 
391 int
test_main(void)392 test_main (void)
393 {
394   size_t i, j, k;
395   const size_t test_len = MIN(TEST_LEN, 3 * 4096);
396   test_init ();
397   check();
398   check2 ();
399   check3 ();
400 
401   printf ("%23s", "");
402   FOR_EACH_IMPL (impl, 0)
403     printf ("\t%s", impl->name);
404   putchar ('\n');
405 
406   for (i = 1; i < 32; ++i)
407     {
408       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 0);
409       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, 1);
410       do_test (CHARBYTES * i, CHARBYTES * i, i, MIDCHAR, -1);
411     }
412 
413   for (i = 1; i < 10 + CHARBYTESLOG; ++i)
414     {
415       do_test (0, 0, 2 << i, MIDCHAR, 0);
416       do_test (0, 0, 2 << i, LARGECHAR, 0);
417       do_test (0, 0, 2 << i, MIDCHAR, 1);
418       do_test (0, 0, 2 << i, LARGECHAR, 1);
419       do_test (0, 0, 2 << i, MIDCHAR, -1);
420       do_test (0, 0, 2 << i, LARGECHAR, -1);
421       do_test (0, CHARBYTES * i, 2 << i, MIDCHAR, 1);
422       do_test (CHARBYTES * i, CHARBYTES * (i + 1), 2 << i, LARGECHAR, 1);
423     }
424 
425   for (i = 1; i < 8; ++i)
426     {
427       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 0);
428       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 0);
429       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, 1);
430       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, 1);
431       do_test (CHARBYTES * i, 2 * CHARBYTES * i, 8 << i, MIDCHAR, -1);
432       do_test (2 * CHARBYTES * i, CHARBYTES * i, 8 << i, LARGECHAR, -1);
433     }
434 
435   for (j = 0; j < 160; ++j)
436     {
437       for (i = 0; i < test_len;)
438         {
439           do_test (getpagesize () - j - 1, 0, i, 127, 0);
440           do_test (getpagesize () - j - 1, 0, i, 127, 1);
441           do_test (getpagesize () - j - 1, 0, i, 127, -1);
442 
443           do_test (getpagesize () - j - 1, j, i, 127, 0);
444           do_test (getpagesize () - j - 1, j, i, 127, 1);
445           do_test (getpagesize () - j - 1, j, i, 127, -1);
446 
447           do_test (0, getpagesize () - j - 1, i, 127, 0);
448           do_test (0, getpagesize () - j - 1, i, 127, 1);
449           do_test (0, getpagesize () - j - 1, i, 127, -1);
450 
451           do_test (j, getpagesize () - j - 1, i, 127, 0);
452           do_test (j, getpagesize () - j - 1, i, 127, 1);
453           do_test (j, getpagesize () - j - 1, i, 127, -1);
454 
455           for (k = 2; k <= 128; k += k)
456             {
457               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, 0);
458               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
459                        0);
460               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, 1);
461               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
462                        1);
463               do_test (getpagesize () - k, getpagesize () - j - 1, i, 127, -1);
464               do_test (getpagesize () - k - 1, getpagesize () - j - 1, i, 127,
465                        -1);
466             }
467 
468           if (i < 32)
469             {
470               i += 1;
471             }
472           else if (i < 161)
473             {
474               i += 7;
475             }
476           else if (i + 161 < test_len)
477             {
478               i += 31;
479               i *= 17;
480               i /= 16;
481               if (i + 161 > test_len)
482                 {
483                   i = test_len - 160;
484                 }
485             }
486           else if (i + 32 < test_len)
487             {
488               i += 7;
489             }
490           else
491             {
492               i += 1;
493             }
494         }
495     }
496 
497   do_random_tests ();
498   return ret;
499 }
500 
501 #include <support/test-driver.c>
502