1/*
  2 * Test cases for printf facility.
  3 */
  4
  5#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  6
  7#include <linux/init.h>
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/printk.h>
 11#include <linux/random.h>
 12#include <linux/slab.h>
 13#include <linux/string.h>
 14
 15#include <linux/bitmap.h>
 16#include <linux/dcache.h>
 17#include <linux/socket.h>
 18#include <linux/in.h>
 19
 20#include <linux/gfp.h>
 21#include <linux/mm.h>
 22
 23#define BUF_SIZE 256
 24#define PAD_SIZE 16
 25#define FILL_CHAR '$'
 26
 27static unsigned total_tests __initdata;
 28static unsigned failed_tests __initdata;
 29static char *test_buffer __initdata;
 30static char *alloced_buffer __initdata;
 31
 32static int __printf(4, 0) __init
 33do_test(int bufsize, const char *expect, int elen,
 34	const char *fmt, va_list ap)
 35{
 36	va_list aq;
 37	int ret, written;
 38
 39	total_tests++;
 40
 41	memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE);
 42	va_copy(aq, ap);
 43	ret = vsnprintf(test_buffer, bufsize, fmt, aq);
 44	va_end(aq);
 45
 46	if (ret != elen) {
 47		pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n",
 48			bufsize, fmt, ret, elen);
 49		return 1;
 50	}
 51
 52	if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) {
 53		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt);
 54		return 1;
 55	}
 56
 57	if (!bufsize) {
 58		if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) {
 59			pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n",
 60				fmt);
 61			return 1;
 62		}
 63		return 0;
 64	}
 65
 66	written = min(bufsize-1, elen);
 67	if (test_buffer[written]) {
 68		pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n",
 69			bufsize, fmt);
 70		return 1;
 71	}
 72
 73	if (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) {
 74		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n",
 75			bufsize, fmt);
 76		return 1;
 77	}
 78
 79	if (memcmp(test_buffer, expect, written)) {
 80		pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n",
 81			bufsize, fmt, test_buffer, written, expect);
 82		return 1;
 83	}
 84	return 0;
 85}
 86
 87static void __printf(3, 4) __init
 88__test(const char *expect, int elen, const char *fmt, ...)
 89{
 90	va_list ap;
 91	int rand;
 92	char *p;
 93
 94	if (elen >= BUF_SIZE) {
 95		pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n",
 96		       elen, fmt);
 97		failed_tests++;
 98		return;
 99	}
100
101	va_start(ap, fmt);
102
103	/*
104	 * Every fmt+args is subjected to four tests: Three where we
105	 * tell vsnprintf varying buffer sizes (plenty, not quite
106	 * enough and 0), and then we also test that kvasprintf would
107	 * be able to print it as expected.
108	 */
109	failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap);
110	rand = 1 + prandom_u32_max(elen+1);
111	/* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */
112	failed_tests += do_test(rand, expect, elen, fmt, ap);
113	failed_tests += do_test(0, expect, elen, fmt, ap);
114
115	p = kvasprintf(GFP_KERNEL, fmt, ap);
116	if (p) {
117		total_tests++;
118		if (memcmp(p, expect, elen+1)) {
119			pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n",
120				fmt, p, expect);
121			failed_tests++;
122		}
123		kfree(p);
124	}
125	va_end(ap);
126}
127
128#define test(expect, fmt, ...)					\
129	__test(expect, strlen(expect), fmt, ##__VA_ARGS__)
130
131static void __init
132test_basic(void)
133{
134	/* Work around annoying "warning: zero-length gnu_printf format string". */
135	char nul = '\0';
136
137	test("", &nul);
138	test("100%", "100%%");
139	test("xxx%yyy", "xxx%cyyy", '%');
140	__test("xxx\0yyy", 7, "xxx%cyyy", '\0');
141}
142
143static void __init
144test_number(void)
145{
146	test("0x1234abcd  ", "%#-12x", 0x1234abcd);
147	test("  0x1234abcd", "%#12x", 0x1234abcd);
148	test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234);
149	test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1);
150	test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1);
151	test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627);
152	/*
153	 * POSIX/C99: »The result of converting zero with an explicit
154	 * precision of zero shall be no characters.« Hence the output
155	 * from the below test should really be "00|0||| ". However,
156	 * the kernel's printf also produces a single 0 in that
157	 * case. This test case simply documents the current
158	 * behaviour.
159	 */
160	test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0);
161#ifndef __CHAR_UNSIGNED__
162	{
163		/*
164		 * Passing a 'char' to a %02x specifier doesn't do
165		 * what was presumably the intention when char is
166		 * signed and the value is negative. One must either &
167		 * with 0xff or cast to u8.
168		 */
169		char val = -16;
170		test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val);
171	}
172#endif
173}
174
175static void __init
176test_string(void)
177{
178	test("", "%s%.0s", "", "123");
179	test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456");
180	test("1  |  2|3  |  4|5  ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5");
181	test("1234      ", "%-10.4s", "123456");
182	test("      1234", "%10.4s", "123456");
183	/*
184	 * POSIX and C99 say that a negative precision (which is only
185	 * possible to pass via a * argument) should be treated as if
186	 * the precision wasn't present, and that if the precision is
187	 * omitted (as in %.s), the precision should be taken to be
188	 * 0. However, the kernel's printf behave exactly opposite,
189	 * treating a negative precision as 0 and treating an omitted
190	 * precision specifier as if no precision was given.
191	 *
192	 * These test cases document the current behaviour; should
193	 * anyone ever feel the need to follow the standards more
194	 * closely, this can be revisited.
195	 */
196	test("    ", "%4.*s", -5, "123456");
197	test("123456", "%.s", "123456");
198	test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c");
199	test("a  |   |   ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c");
200}
201
202#define PLAIN_BUF_SIZE 64	/* leave some space so we don't oops */
203
204#if BITS_PER_LONG == 64
205
206#define PTR_WIDTH 16
207#define PTR ((void *)0xffff0123456789ab)
208#define PTR_STR "ffff0123456789ab"
209#define ZEROS "00000000"	/* hex 32 zero bits */
210
211static int __init
212plain_format(void)
213{
214	char buf[PLAIN_BUF_SIZE];
215	int nchars;
216
217	nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR);
218
219	if (nchars != PTR_WIDTH || strncmp(buf, ZEROS, strlen(ZEROS)) != 0)
220		return -1;
221
222	return 0;
223}
224
225#else
226
227#define PTR_WIDTH 8
228#define PTR ((void *)0x456789ab)
229#define PTR_STR "456789ab"
230
231static int __init
232plain_format(void)
233{
234	/* Format is implicitly tested for 32 bit machines by plain_hash() */
235	return 0;
236}
237
238#endif	/* BITS_PER_LONG == 64 */
239
240static int __init
241plain_hash(void)
242{
243	char buf[PLAIN_BUF_SIZE];
244	int nchars;
245
246	nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR);
247
248	if (nchars != PTR_WIDTH || strncmp(buf, PTR_STR, PTR_WIDTH) == 0)
249		return -1;
250
251	return 0;
252}
253
254/*
255 * We can't use test() to test %p because we don't know what output to expect
256 * after an address is hashed.
257 */
258static void __init
259plain(void)
260{
261	int err;
262
263	err = plain_hash();
264	if (err) {
265		pr_warn("plain 'p' does not appear to be hashed\n");
266		failed_tests++;
267		return;
268	}
269
270	err = plain_format();
271	if (err) {
272		pr_warn("hashing plain 'p' has unexpected format\n");
273		failed_tests++;
274	}
275}
276
277static void __init
278symbol_ptr(void)
279{
280}
281
282static void __init
283kernel_ptr(void)
284{
285	/* We can't test this without access to kptr_restrict. */
286}
287
288static void __init
289struct_resource(void)
290{
291}
292
293static void __init
294addr(void)
295{
296}
297
298static void __init
299escaped_str(void)
300{
301}
302
303static void __init
304hex_string(void)
305{
306	const char buf[3] = {0xc0, 0xff, 0xee};
307
308	test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",
309	     "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf);
310	test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee",
311	     "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf);
312}
313
314static void __init
315mac(void)
316{
317	const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05};
318
319	test("2d:48:d6:fc:7a:05", "%pM", addr);
320	test("05:7a:fc:d6:48:2d", "%pMR", addr);
321	test("2d-48-d6-fc-7a-05", "%pMF", addr);
322	test("2d48d6fc7a05", "%pm", addr);
323	test("057afcd6482d", "%pmR", addr);
324}
325
326static void __init
327ip4(void)
328{
329	struct sockaddr_in sa;
330
331	sa.sin_family = AF_INET;
332	sa.sin_port = cpu_to_be16(12345);
333	sa.sin_addr.s_addr = cpu_to_be32(0x7f000001);
334
335	test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr);
336	test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa);
337	sa.sin_addr.s_addr = cpu_to_be32(0x01020304);
338	test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa);
339}
340
341static void __init
342ip6(void)
343{
344}
345
346static void __init
347ip(void)
348{
349	ip4();
350	ip6();
351}
352
353static void __init
354uuid(void)
355{
356	const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
357			       0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf};
358
359	test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid);
360	test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid);
361	test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid);
362	test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid);
363}
364
365static struct dentry test_dentry[4] __initdata = {
366	{ .d_parent = &test_dentry[0],
367	  .d_name = QSTR_INIT(test_dentry[0].d_iname, 3),
368	  .d_iname = "foo" },
369	{ .d_parent = &test_dentry[0],
370	  .d_name = QSTR_INIT(test_dentry[1].d_iname, 5),
371	  .d_iname = "bravo" },
372	{ .d_parent = &test_dentry[1],
373	  .d_name = QSTR_INIT(test_dentry[2].d_iname, 4),
374	  .d_iname = "alfa" },
375	{ .d_parent = &test_dentry[2],
376	  .d_name = QSTR_INIT(test_dentry[3].d_iname, 5),
377	  .d_iname = "romeo" },
378};
379
380static void __init
381dentry(void)
382{
383	test("foo", "%pd", &test_dentry[0]);
384	test("foo", "%pd2", &test_dentry[0]);
385
386	test("romeo", "%pd", &test_dentry[3]);
387	test("alfa/romeo", "%pd2", &test_dentry[3]);
388	test("bravo/alfa/romeo", "%pd3", &test_dentry[3]);
389	test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]);
390	test("/bravo/alfa", "%pd4", &test_dentry[2]);
391
392	test("bravo/alfa  |bravo/alfa  ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]);
393	test("  bravo/alfa|  bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]);
394}
395
396static void __init
397struct_va_format(void)
398{
399}
400
401static void __init
402struct_clk(void)
403{
404}
405
406static void __init
407large_bitmap(void)
408{
409	const int nbits = 1 << 16;
410	unsigned long *bits = kcalloc(BITS_TO_LONGS(nbits), sizeof(long), GFP_KERNEL);
411	if (!bits)
412		return;
413
414	bitmap_set(bits, 1, 20);
415	bitmap_set(bits, 60000, 15);
416	test("1-20,60000-60014", "%*pbl", nbits, bits);
417	kfree(bits);
418}
419
420static void __init
421bitmap(void)
422{
423	DECLARE_BITMAP(bits, 20);
424	const int primes[] = {2,3,5,7,11,13,17,19};
425	int i;
426
427	bitmap_zero(bits, 20);
428	test("00000|00000", "%20pb|%*pb", bits, 20, bits);
429	test("|", "%20pbl|%*pbl", bits, 20, bits);
430
431	for (i = 0; i < ARRAY_SIZE(primes); ++i)
432		set_bit(primes[i], bits);
433	test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits);
434	test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits);
435
436	bitmap_fill(bits, 20);
437	test("fffff|fffff", "%20pb|%*pb", bits, 20, bits);
438	test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits);
439
440	large_bitmap();
441}
442
443static void __init
444netdev_features(void)
445{
446}
447
448static void __init
449flags(void)
450{
451	unsigned long flags;
452	gfp_t gfp;
453	char *cmp_buffer;
454
455	flags = 0;
456	test("", "%pGp", &flags);
457
458	/* Page flags should filter the zone id */
459	flags = 1UL << NR_PAGEFLAGS;
460	test("", "%pGp", &flags);
461
462	flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru
463		| 1UL << PG_active | 1UL << PG_swapbacked;
464	test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags);
465
466
467	flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC
468			| VM_DENYWRITE;
469	test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags);
470
471	gfp = GFP_TRANSHUGE;
472	test("GFP_TRANSHUGE", "%pGg", &gfp);
473
474	gfp = GFP_ATOMIC|__GFP_DMA;
475	test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp);
476
477	gfp = __GFP_ATOMIC;
478	test("__GFP_ATOMIC", "%pGg", &gfp);
479
480	cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL);
481	if (!cmp_buffer)
482		return;
483
484	/* Any flags not translated by the table should remain numeric */
485	gfp = ~__GFP_BITS_MASK;
486	snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp);
487	test(cmp_buffer, "%pGg", &gfp);
488
489	snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx",
490							(unsigned long) gfp);
491	gfp |= __GFP_ATOMIC;
492	test(cmp_buffer, "%pGg", &gfp);
493
494	kfree(cmp_buffer);
495}
496
497static void __init
498test_pointer(void)
499{
500	plain();
501	symbol_ptr();
502	kernel_ptr();
503	struct_resource();
504	addr();
505	escaped_str();
506	hex_string();
507	mac();
508	ip();
509	uuid();
510	dentry();
511	struct_va_format();
512	struct_clk();
513	bitmap();
514	netdev_features();
515	flags();
516}
517
518static int __init
519test_printf_init(void)
520{
521	alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL);
522	if (!alloced_buffer)
523		return -ENOMEM;
524	test_buffer = alloced_buffer + PAD_SIZE;
525
526	test_basic();
527	test_number();
528	test_string();
529	test_pointer();
530
531	kfree(alloced_buffer);
532
533	if (failed_tests == 0)
534		pr_info("all %u tests passed\n", total_tests);
535	else
536		pr_warn("failed %u out of %u tests\n", failed_tests, total_tests);
537
538	return failed_tests ? -EINVAL : 0;
539}
540
541module_init(test_printf_init);
542
543MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>");
544MODULE_LICENSE("GPL");