1 /* Copyright (c) 2014 Red Hat, Inc. 2 * 3 * This program is free software: you can redistribute it and/or modify 4 * it under the terms of version 2 the GNU General Public License as 5 * published by the Free Software Foundation. 6 * 7 * This program is distributed in the hope that it will be useful, 8 * but WITHOUT ANY WARRANTY; without even the implied warranty of 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 10 * GNU General Public License for more details. 11 * 12 * You should have received a copy of the GNU General Public License 13 * along with this program. If not, see <http://www.gnu.org/licenses/>. 14 *********************************************************************** 15 * File: mountns04.c 16 * 17 * Tests an unbindable mount: unbindable mount is an unbindable 18 * private mount. 19 * Description: 20 * 1. Creates directories "A", "B" and files "A/A", "B/B" 21 * 2. Unshares mount namespace and makes it private (so mounts/umounts 22 * have no effect on a real system) 23 * 3. Bind mounts directory "A" to "A" 24 * 4. Makes directory directory "A" unbindable 25 * 5. Tries to bind mount unbindable "A" to "B": 26 * - if it fails, test passes 27 * - if it passes, test fails 28 ***********************************************************************/ 29 30 #define _GNU_SOURCE 31 #include <sys/wait.h> 32 #include <sys/mount.h> 33 #include <stdio.h> 34 #include <errno.h> 35 #include "test.h" 36 #include "libclone.h" 37 #include "safe_macros.h" 38 #include "mountns_helper.h" 39 40 41 char *TCID = "mountns04"; 42 int TST_TOTAL = 1; 43 44 45 #if defined(MS_SHARED) && defined(MS_PRIVATE) \ 46 && defined(MS_REC) && defined(MS_UNBINDABLE) 47 48 static void test(void) 49 { 50 /* unshares the mount ns */ 51 if (unshare(CLONE_NEWNS) == -1) 52 tst_brkm(TBROK | TERRNO, cleanup, "unshare failed"); 53 /* makes sure mounts/umounts have no effect on a real system */ 54 SAFE_MOUNT(cleanup, "none", "/", "none", MS_REC|MS_PRIVATE, NULL); 55 56 /* bind mounts DIRA to itself */ 57 SAFE_MOUNT(cleanup, DIRA, DIRA, "none", MS_BIND, NULL); 58 /* makes mount DIRA unbindable */ 59 SAFE_MOUNT(cleanup, "none", DIRA, "none", MS_UNBINDABLE, NULL); 60 61 /* tries to bind mount unbindable DIRA to DIRB which should fail */ 62 if (mount(DIRA, DIRB, "none", MS_BIND, NULL) == -1) { 63 tst_resm(TPASS, "unbindable mount passed"); 64 } else { 65 SAFE_UMOUNT(cleanup, DIRB); 66 tst_resm(TFAIL, "unbindable mount faled"); 67 } 68 69 SAFE_UMOUNT(cleanup, DIRA); 70 } 71 72 int main(int argc, char *argv[]) 73 { 74 int lc; 75 76 tst_parse_opts(argc, argv, NULL, NULL); 77 78 setup(); 79 80 for (lc = 0; TEST_LOOPING(lc); lc++) 81 test(); 82 83 cleanup(); 84 tst_exit(); 85 } 86 87 #else 88 int main(void) 89 { 90 tst_brkm(TCONF, NULL, "needed mountflags are not defined"); 91 } 92 #endif 93