1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License version 2. 4 * 5 * This program is distributed in the hope that it will be useful, 6 * but WITHOUT ANY WARRANTY; without even the implied warranty of 7 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 8 * GNU General Public License for more details. 9 * 10 * Test that the mlock() function sets errno = EPERM if the calling process 11 * does not have the appropriate privilege to perform the requested operation 12 * (Linux 2.6.9 and later) and its RLIMIT_MEMLOCK soft resource limit set to 0. 13 */ 14 15 #define _XOPEN_SOURCE 600 16 17 #include <sys/mman.h> 18 #include <stdio.h> 19 #include <unistd.h> 20 #include <stdlib.h> 21 #include <errno.h> 22 #include <sys/types.h> 23 #include <pwd.h> 24 #include <string.h> 25 #include <sys/resource.h> 26 #include "posixtest.h" 27 28 #define BUFSIZE 8 29 30 /** Set the euid of this process to a non-root uid */ set_nonroot()31int set_nonroot() 32 { 33 struct passwd *pw; 34 struct rlimit rlim; 35 int ret = 0; 36 37 setpwent(); 38 /* search for the first user which is non root */ 39 while ((pw = getpwent()) != NULL) 40 if (strcmp(pw->pw_name, "root")) 41 break; 42 endpwent(); 43 if (pw == NULL) { 44 printf("There is no other user than current and root.\n"); 45 return 1; 46 } 47 48 /* 49 * mlock() 50 * EPERM: 51 * (Linux 2.6.9 and later) the caller was not privileged (CAP_IPC_LOCK) 52 * and its RLIMIT_MEMLOCK soft resource limit was 0. 53 */ 54 55 rlim.rlim_cur = 0; 56 rlim.rlim_max = 0; 57 if ((ret = setrlimit(RLIMIT_MEMLOCK, &rlim)) != 0) 58 printf("Failed at setrlimit() return %d \n", ret); 59 60 if (seteuid(pw->pw_uid) != 0) { 61 if (errno == EPERM) { 62 printf 63 ("You don't have permission to change your UID.\n"); 64 return 1; 65 } 66 perror("An error occurs when calling seteuid()"); 67 return 1; 68 } 69 70 printf("Testing with user '%s' (uid: %d)\n", 71 pw->pw_name, (int)geteuid()); 72 return 0; 73 } 74 main(void)75int main(void) 76 { 77 int result; 78 void *ptr; 79 80 /* This test should be run under standard user permissions */ 81 if (getuid() == 0) { 82 if (set_nonroot() != 0) { 83 printf("Cannot run this test as non-root user\n"); 84 return PTS_UNTESTED; 85 } 86 } 87 88 ptr = malloc(BUFSIZE); 89 if (ptr == NULL) { 90 printf("Can not allocate memory.\n"); 91 return PTS_UNRESOLVED; 92 } 93 94 result = mlock(ptr, BUFSIZE); 95 96 if (result == -1 && errno == EPERM) { 97 printf("Test PASSED\n"); 98 return PTS_PASS; 99 } else if (result == 0) { 100 printf("You have the right to call mlock\n"); 101 return PTS_FAIL; 102 } else { 103 perror("Unexpected error"); 104 return PTS_UNRESOLVED; 105 } 106 107 } 108