/* * Test cases for printf facility. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/printk.h> #include <linux/random.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/bitmap.h> #include <linux/dcache.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/gfp.h> #include <linux/mm.h> #define BUF_SIZE 256 #define PAD_SIZE 16 #define FILL_CHAR '$' static unsigned total_tests __initdata; static unsigned failed_tests __initdata; static char *test_buffer __initdata; static char *alloced_buffer __initdata; static int __printf(4, 0) __init do_test(int bufsize, const char *expect, int elen, const char *fmt, va_list ap) { va_list aq; int ret, written; total_tests++; memset(alloced_buffer, FILL_CHAR, BUF_SIZE + 2*PAD_SIZE); va_copy(aq, ap); ret = vsnprintf(test_buffer, bufsize, fmt, aq); va_end(aq); if (ret != elen) { pr_warn("vsnprintf(buf, %d, \"%s\", ...) returned %d, expected %d\n", bufsize, fmt, ret, elen); return 1; } if (memchr_inv(alloced_buffer, FILL_CHAR, PAD_SIZE)) { pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote before buffer\n", bufsize, fmt); return 1; } if (!bufsize) { if (memchr_inv(test_buffer, FILL_CHAR, BUF_SIZE + PAD_SIZE)) { pr_warn("vsnprintf(buf, 0, \"%s\", ...) wrote to buffer\n", fmt); return 1; } return 0; } written = min(bufsize-1, elen); if (test_buffer[written]) { pr_warn("vsnprintf(buf, %d, \"%s\", ...) did not nul-terminate buffer\n", bufsize, fmt); return 1; } if (memchr_inv(test_buffer + written + 1, FILL_CHAR, BUF_SIZE + PAD_SIZE - (written + 1))) { pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote beyond the nul-terminator\n", bufsize, fmt); return 1; } if (memcmp(test_buffer, expect, written)) { pr_warn("vsnprintf(buf, %d, \"%s\", ...) wrote '%s', expected '%.*s'\n", bufsize, fmt, test_buffer, written, expect); return 1; } return 0; } static void __printf(3, 4) __init __test(const char *expect, int elen, const char *fmt, ...) { va_list ap; int rand; char *p; if (elen >= BUF_SIZE) { pr_err("error in test suite: expected output length %d too long. Format was '%s'.\n", elen, fmt); failed_tests++; return; } va_start(ap, fmt); /* * Every fmt+args is subjected to four tests: Three where we * tell vsnprintf varying buffer sizes (plenty, not quite * enough and 0), and then we also test that kvasprintf would * be able to print it as expected. */ failed_tests += do_test(BUF_SIZE, expect, elen, fmt, ap); rand = 1 + prandom_u32_max(elen+1); /* Since elen < BUF_SIZE, we have 1 <= rand <= BUF_SIZE. */ failed_tests += do_test(rand, expect, elen, fmt, ap); failed_tests += do_test(0, expect, elen, fmt, ap); p = kvasprintf(GFP_KERNEL, fmt, ap); if (p) { total_tests++; if (memcmp(p, expect, elen+1)) { pr_warn("kvasprintf(..., \"%s\", ...) returned '%s', expected '%s'\n", fmt, p, expect); failed_tests++; } kfree(p); } va_end(ap); } #define test(expect, fmt, ...) \ __test(expect, strlen(expect), fmt, ##__VA_ARGS__) static void __init test_basic(void) { /* Work around annoying "warning: zero-length gnu_printf format string". */ char nul = '\0'; test("", &nul); test("100%", "100%%"); test("xxx%yyy", "xxx%cyyy", '%'); __test("xxx\0yyy", 7, "xxx%cyyy", '\0'); } static void __init test_number(void) { test("0x1234abcd ", "%#-12x", 0x1234abcd); test(" 0x1234abcd", "%#12x", 0x1234abcd); test("0|001| 12|+123| 1234|-123|-1234", "%d|%03d|%3d|%+d|% d|%+d|% d", 0, 1, 12, 123, 1234, -123, -1234); test("0|1|1|128|255", "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); test("0|1|1|-128|-1", "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); /* * POSIX/C99: »The result of converting zero with an explicit * precision of zero shall be no characters.« Hence the output * from the below test should really be "00|0||| ". However, * the kernel's printf also produces a single 0 in that * case. This test case simply documents the current * behaviour. */ test("00|0|0|0|0", "%.2d|%.1d|%.0d|%.*d|%1.0d", 0, 0, 0, 0, 0, 0); #ifndef __CHAR_UNSIGNED__ { /* * Passing a 'char' to a %02x specifier doesn't do * what was presumably the intention when char is * signed and the value is negative. One must either & * with 0xff or cast to u8. */ char val = -16; test("0xfffffff0|0xf0|0xf0", "%#02x|%#02x|%#02x", val, val & 0xff, (u8)val); } #endif } static void __init test_string(void) { test("", "%s%.0s", "", "123"); test("ABCD|abc|123", "%s|%.3s|%.*s", "ABCD", "abcdef", 3, "123456"); test("1 | 2|3 | 4|5 ", "%-3s|%3s|%-*s|%*s|%*s", "1", "2", 3, "3", 3, "4", -3, "5"); test("1234 ", "%-10.4s", "123456"); test(" 1234", "%10.4s", "123456"); /* * POSIX and C99 say that a negative precision (which is only * possible to pass via a * argument) should be treated as if * the precision wasn't present, and that if the precision is * omitted (as in %.s), the precision should be taken to be * 0. However, the kernel's printf behave exactly opposite, * treating a negative precision as 0 and treating an omitted * precision specifier as if no precision was given. * * These test cases document the current behaviour; should * anyone ever feel the need to follow the standards more * closely, this can be revisited. */ test(" ", "%4.*s", -5, "123456"); test("123456", "%.s", "123456"); test("a||", "%.s|%.0s|%.*s", "a", "b", 0, "c"); test("a | | ", "%-3.s|%-3.0s|%-3.*s", "a", "b", 0, "c"); } #define PLAIN_BUF_SIZE 64 /* leave some space so we don't oops */ #if BITS_PER_LONG == 64 #define PTR_WIDTH 16 #define PTR ((void *)0xffff0123456789abUL) #define PTR_STR "ffff0123456789ab" #define PTR_VAL_NO_CRNG "(____ptrval____)" #define ZEROS "00000000" /* hex 32 zero bits */ static int __init plain_format(void) { char buf[PLAIN_BUF_SIZE]; int nchars; nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR); if (nchars != PTR_WIDTH) return -1; if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", PTR_VAL_NO_CRNG); return 0; } if (strncmp(buf, ZEROS, strlen(ZEROS)) != 0) return -1; return 0; } #else #define PTR_WIDTH 8 #define PTR ((void *)0x456789ab) #define PTR_STR "456789ab" #define PTR_VAL_NO_CRNG "(ptrval)" static int __init plain_format(void) { /* Format is implicitly tested for 32 bit machines by plain_hash() */ return 0; } #endif /* BITS_PER_LONG == 64 */ static int __init plain_hash(void) { char buf[PLAIN_BUF_SIZE]; int nchars; nchars = snprintf(buf, PLAIN_BUF_SIZE, "%p", PTR); if (nchars != PTR_WIDTH) return -1; if (strncmp(buf, PTR_VAL_NO_CRNG, PTR_WIDTH) == 0) { pr_warn("crng possibly not yet initialized. plain 'p' buffer contains \"%s\"", PTR_VAL_NO_CRNG); return 0; } if (strncmp(buf, PTR_STR, PTR_WIDTH) == 0) return -1; return 0; } /* * We can't use test() to test %p because we don't know what output to expect * after an address is hashed. */ static void __init plain(void) { int err; err = plain_hash(); if (err) { pr_warn("plain 'p' does not appear to be hashed\n"); failed_tests++; return; } err = plain_format(); if (err) { pr_warn("hashing plain 'p' has unexpected format\n"); failed_tests++; } } static void __init symbol_ptr(void) { } static void __init kernel_ptr(void) { /* We can't test this without access to kptr_restrict. */ } static void __init struct_resource(void) { } static void __init addr(void) { } static void __init escaped_str(void) { } static void __init hex_string(void) { const char buf[3] = {0xc0, 0xff, 0xee}; test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", "%3ph|%3phC|%3phD|%3phN", buf, buf, buf, buf); test("c0 ff ee|c0:ff:ee|c0-ff-ee|c0ffee", "%*ph|%*phC|%*phD|%*phN", 3, buf, 3, buf, 3, buf, 3, buf); } static void __init mac(void) { const u8 addr[6] = {0x2d, 0x48, 0xd6, 0xfc, 0x7a, 0x05}; test("2d:48:d6:fc:7a:05", "%pM", addr); test("05:7a:fc:d6:48:2d", "%pMR", addr); test("2d-48-d6-fc-7a-05", "%pMF", addr); test("2d48d6fc7a05", "%pm", addr); test("057afcd6482d", "%pmR", addr); } static void __init ip4(void) { struct sockaddr_in sa; sa.sin_family = AF_INET; sa.sin_port = cpu_to_be16(12345); sa.sin_addr.s_addr = cpu_to_be32(0x7f000001); test("127.000.000.001|127.0.0.1", "%pi4|%pI4", &sa.sin_addr, &sa.sin_addr); test("127.000.000.001|127.0.0.1", "%piS|%pIS", &sa, &sa); sa.sin_addr.s_addr = cpu_to_be32(0x01020304); test("001.002.003.004:12345|1.2.3.4:12345", "%piSp|%pISp", &sa, &sa); } static void __init ip6(void) { } static void __init ip(void) { ip4(); ip6(); } static void __init uuid(void) { const char uuid[16] = {0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf}; test("00010203-0405-0607-0809-0a0b0c0d0e0f", "%pUb", uuid); test("00010203-0405-0607-0809-0A0B0C0D0E0F", "%pUB", uuid); test("03020100-0504-0706-0809-0a0b0c0d0e0f", "%pUl", uuid); test("03020100-0504-0706-0809-0A0B0C0D0E0F", "%pUL", uuid); } static struct dentry test_dentry[4] __initdata = { { .d_parent = &test_dentry[0], .d_name = QSTR_INIT(test_dentry[0].d_iname, 3), .d_iname = "foo" }, { .d_parent = &test_dentry[0], .d_name = QSTR_INIT(test_dentry[1].d_iname, 5), .d_iname = "bravo" }, { .d_parent = &test_dentry[1], .d_name = QSTR_INIT(test_dentry[2].d_iname, 4), .d_iname = "alfa" }, { .d_parent = &test_dentry[2], .d_name = QSTR_INIT(test_dentry[3].d_iname, 5), .d_iname = "romeo" }, }; static void __init dentry(void) { test("foo", "%pd", &test_dentry[0]); test("foo", "%pd2", &test_dentry[0]); test("romeo", "%pd", &test_dentry[3]); test("alfa/romeo", "%pd2", &test_dentry[3]); test("bravo/alfa/romeo", "%pd3", &test_dentry[3]); test("/bravo/alfa/romeo", "%pd4", &test_dentry[3]); test("/bravo/alfa", "%pd4", &test_dentry[2]); test("bravo/alfa |bravo/alfa ", "%-12pd2|%*pd2", &test_dentry[2], -12, &test_dentry[2]); test(" bravo/alfa| bravo/alfa", "%12pd2|%*pd2", &test_dentry[2], 12, &test_dentry[2]); } static void __init struct_va_format(void) { } static void __init struct_clk(void) { } static void __init large_bitmap(void) { const int nbits = 1 << 16; unsigned long *bits = kcalloc(BITS_TO_LONGS(nbits), sizeof(long), GFP_KERNEL); if (!bits) return; bitmap_set(bits, 1, 20); bitmap_set(bits, 60000, 15); test("1-20,60000-60014", "%*pbl", nbits, bits); kfree(bits); } static void __init bitmap(void) { DECLARE_BITMAP(bits, 20); const int primes[] = {2,3,5,7,11,13,17,19}; int i; bitmap_zero(bits, 20); test("00000|00000", "%20pb|%*pb", bits, 20, bits); test("|", "%20pbl|%*pbl", bits, 20, bits); for (i = 0; i < ARRAY_SIZE(primes); ++i) set_bit(primes[i], bits); test("a28ac|a28ac", "%20pb|%*pb", bits, 20, bits); test("2-3,5,7,11,13,17,19|2-3,5,7,11,13,17,19", "%20pbl|%*pbl", bits, 20, bits); bitmap_fill(bits, 20); test("fffff|fffff", "%20pb|%*pb", bits, 20, bits); test("0-19|0-19", "%20pbl|%*pbl", bits, 20, bits); large_bitmap(); } static void __init netdev_features(void) { } static void __init flags(void) { unsigned long flags; gfp_t gfp; char *cmp_buffer; flags = 0; test("", "%pGp", &flags); /* Page flags should filter the zone id */ flags = 1UL << NR_PAGEFLAGS; test("", "%pGp", &flags); flags |= 1UL << PG_uptodate | 1UL << PG_dirty | 1UL << PG_lru | 1UL << PG_active | 1UL << PG_swapbacked; test("uptodate|dirty|lru|active|swapbacked", "%pGp", &flags); flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC | VM_DENYWRITE; test("read|exec|mayread|maywrite|mayexec|denywrite", "%pGv", &flags); gfp = GFP_TRANSHUGE; test("GFP_TRANSHUGE", "%pGg", &gfp); gfp = GFP_ATOMIC|__GFP_DMA; test("GFP_ATOMIC|GFP_DMA", "%pGg", &gfp); gfp = __GFP_ATOMIC; test("__GFP_ATOMIC", "%pGg", &gfp); cmp_buffer = kmalloc(BUF_SIZE, GFP_KERNEL); if (!cmp_buffer) return; /* Any flags not translated by the table should remain numeric */ gfp = ~__GFP_BITS_MASK; snprintf(cmp_buffer, BUF_SIZE, "%#lx", (unsigned long) gfp); test(cmp_buffer, "%pGg", &gfp); snprintf(cmp_buffer, BUF_SIZE, "__GFP_ATOMIC|%#lx", (unsigned long) gfp); gfp |= __GFP_ATOMIC; test(cmp_buffer, "%pGg", &gfp); kfree(cmp_buffer); } static void __init test_pointer(void) { plain(); symbol_ptr(); kernel_ptr(); struct_resource(); addr(); escaped_str(); hex_string(); mac(); ip(); uuid(); dentry(); struct_va_format(); struct_clk(); bitmap(); netdev_features(); flags(); } static int __init test_printf_init(void) { alloced_buffer = kmalloc(BUF_SIZE + 2*PAD_SIZE, GFP_KERNEL); if (!alloced_buffer) return -ENOMEM; test_buffer = alloced_buffer + PAD_SIZE; test_basic(); test_number(); test_string(); test_pointer(); kfree(alloced_buffer); if (failed_tests == 0) pr_info("all %u tests passed\n", total_tests); else pr_warn("failed %u out of %u tests\n", failed_tests, total_tests); return failed_tests ? -EINVAL : 0; } module_init(test_printf_init); MODULE_AUTHOR("Rasmus Villemoes <linux@rasmusvillemoes.dk>"); MODULE_LICENSE("GPL");