1 // SPDX-License-Identifier: GPL-2.0 2 #include <malloc.h> 3 #include <stdlib.h> 4 #include <string.h> 5 #include <sys/mman.h> 6 #include <time.h> 7 8 #include "utils.h" 9 10 #define SIZE 256 11 #define ITERATIONS 10000 12 13 #define LARGE_SIZE (5 * 1024) 14 #define LARGE_ITERATIONS 1000 15 #define LARGE_MAX_OFFSET 32 16 #define LARGE_SIZE_START 4096 17 18 /* This is big enough to fit LARGE_SIZE and works on 4K & 64K kernels */ 19 #define MAP_SIZE (64 * 1024) 20 21 #define MAX_OFFSET_DIFF_S1_S2 48 22 23 int vmx_count; 24 int enter_vmx_ops(void) 25 { 26 vmx_count++; 27 return 1; 28 } 29 30 void exit_vmx_ops(void) 31 { 32 vmx_count--; 33 } 34 int test_memcmp(const void *s1, const void *s2, size_t n); 35 36 /* test all offsets and lengths */ 37 static void test_one(char *s1, char *s2, unsigned long max_offset, 38 unsigned long size_start, unsigned long max_size) 39 { 40 unsigned long offset, size; 41 42 for (offset = 0; offset < max_offset; offset++) { 43 for (size = size_start; size < (max_size - offset); size++) { 44 int x, y; 45 unsigned long i; 46 47 y = memcmp(s1+offset, s2+offset, size); 48 x = test_memcmp(s1+offset, s2+offset, size); 49 50 if (((x ^ y) < 0) && /* Trick to compare sign */ 51 ((x | y) != 0)) { /* check for zero */ 52 printf("memcmp returned %d, should have returned %d (offset %ld size %ld)\n", x, y, offset, size); 53 54 for (i = offset; i < offset+size; i++) 55 printf("%02x ", s1[i]); 56 printf("\n"); 57 58 for (i = offset; i < offset+size; i++) 59 printf("%02x ", s2[i]); 60 printf("\n"); 61 abort(); 62 } 63 64 if (vmx_count != 0) { 65 printf("vmx enter/exit not paired.(offset:%ld size:%ld s1:%p s2:%p vc:%d\n", 66 offset, size, s1, s2, vmx_count); 67 printf("\n"); 68 abort(); 69 } 70 } 71 } 72 } 73 74 static int testcase(bool islarge) 75 { 76 unsigned long i, comp_size, alloc_size; 77 char *p, *s1, *s2; 78 int iterations; 79 80 comp_size = (islarge ? LARGE_SIZE : SIZE); 81 alloc_size = comp_size + MAX_OFFSET_DIFF_S1_S2; 82 iterations = islarge ? LARGE_ITERATIONS : ITERATIONS; 83 84 p = mmap(NULL, 4 * MAP_SIZE, PROT_READ | PROT_WRITE, 85 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); 86 FAIL_IF(p == MAP_FAILED); 87 88 /* Put s1/s2 at the end of a page */ 89 s1 = p + MAP_SIZE - alloc_size; 90 s2 = p + 3 * MAP_SIZE - alloc_size; 91 92 /* And unmap the subsequent page to force a fault if we overread */ 93 munmap(p + MAP_SIZE, MAP_SIZE); 94 munmap(p + 3 * MAP_SIZE, MAP_SIZE); 95 96 srandom(time(0)); 97 98 for (i = 0; i < iterations; i++) { 99 unsigned long j; 100 unsigned long change; 101 char *rand_s1 = s1; 102 char *rand_s2 = s2; 103 104 for (j = 0; j < alloc_size; j++) 105 s1[j] = random(); 106 107 rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2; 108 rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2; 109 memcpy(rand_s2, rand_s1, comp_size); 110 111 /* change one byte */ 112 change = random() % comp_size; 113 rand_s2[change] = random() & 0xff; 114 115 if (islarge) 116 test_one(rand_s1, rand_s2, LARGE_MAX_OFFSET, 117 LARGE_SIZE_START, comp_size); 118 else 119 test_one(rand_s1, rand_s2, SIZE, 0, comp_size); 120 } 121 122 srandom(time(0)); 123 124 for (i = 0; i < iterations; i++) { 125 unsigned long j; 126 unsigned long change; 127 char *rand_s1 = s1; 128 char *rand_s2 = s2; 129 130 for (j = 0; j < alloc_size; j++) 131 s1[j] = random(); 132 133 rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2; 134 rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2; 135 memcpy(rand_s2, rand_s1, comp_size); 136 137 /* change multiple bytes, 1/8 of total */ 138 for (j = 0; j < comp_size / 8; j++) { 139 change = random() % comp_size; 140 s2[change] = random() & 0xff; 141 } 142 143 if (islarge) 144 test_one(rand_s1, rand_s2, LARGE_MAX_OFFSET, 145 LARGE_SIZE_START, comp_size); 146 else 147 test_one(rand_s1, rand_s2, SIZE, 0, comp_size); 148 } 149 150 return 0; 151 } 152 153 static int testcases(void) 154 { 155 #ifdef __powerpc64__ 156 // vcmpequd used in memcmp_64.S is v2.07 157 SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07)); 158 #endif 159 160 testcase(0); 161 testcase(1); 162 return 0; 163 } 164 165 int main(void) 166 { 167 test_harness_set_timeout(300); 168 return test_harness(testcases, "memcmp"); 169 } 170