1 /* 2 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com> 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 /* Test readlink /proc/self/map_files/... with minimum address. */ 17 #include <errno.h> 18 #include <sys/types.h> 19 #include <sys/stat.h> 20 #include <fcntl.h> 21 #include <stdio.h> 22 #include <unistd.h> 23 #include <sys/mman.h> 24 #include <stdlib.h> 25 26 static void pass(const char *fmt, unsigned long a, unsigned long b) 27 { 28 char name[64]; 29 char buf[64]; 30 31 snprintf(name, sizeof(name), fmt, a, b); 32 if (readlink(name, buf, sizeof(buf)) == -1) 33 exit(1); 34 } 35 36 static void fail(const char *fmt, unsigned long a, unsigned long b) 37 { 38 char name[64]; 39 char buf[64]; 40 41 snprintf(name, sizeof(name), fmt, a, b); 42 if (readlink(name, buf, sizeof(buf)) == -1 && errno == ENOENT) 43 return; 44 exit(1); 45 } 46 47 int main(void) 48 { 49 const int PAGE_SIZE = sysconf(_SC_PAGESIZE); 50 const unsigned long va_max = 1UL << 32; 51 unsigned long va; 52 void *p; 53 int fd; 54 unsigned long a, b; 55 56 fd = open("/dev/zero", O_RDONLY); 57 if (fd == -1) 58 return 1; 59 60 for (va = 0; va < va_max; va += PAGE_SIZE) { 61 p = mmap((void *)va, PAGE_SIZE, PROT_NONE, MAP_PRIVATE|MAP_FILE|MAP_FIXED, fd, 0); 62 if (p == (void *)va) 63 break; 64 } 65 if (va == va_max) { 66 fprintf(stderr, "error: mmap doesn't like you\n"); 67 return 1; 68 } 69 70 a = (unsigned long)p; 71 b = (unsigned long)p + PAGE_SIZE; 72 73 pass("/proc/self/map_files/%lx-%lx", a, b); 74 fail("/proc/self/map_files/ %lx-%lx", a, b); 75 fail("/proc/self/map_files/%lx -%lx", a, b); 76 fail("/proc/self/map_files/%lx- %lx", a, b); 77 fail("/proc/self/map_files/%lx-%lx ", a, b); 78 fail("/proc/self/map_files/0%lx-%lx", a, b); 79 fail("/proc/self/map_files/%lx-0%lx", a, b); 80 if (sizeof(long) == 4) { 81 fail("/proc/self/map_files/100000000%lx-%lx", a, b); 82 fail("/proc/self/map_files/%lx-100000000%lx", a, b); 83 } else if (sizeof(long) == 8) { 84 fail("/proc/self/map_files/10000000000000000%lx-%lx", a, b); 85 fail("/proc/self/map_files/%lx-10000000000000000%lx", a, b); 86 } else 87 return 1; 88 89 return 0; 90 } 91