1 /* 2 * Copyright (c) 2019 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 that pointing #! script interpreter to self doesn't recurse. */ 17 #include <errno.h> 18 #include <sched.h> 19 #include <stdio.h> 20 #include <string.h> 21 #include <sys/types.h> 22 #include <sys/stat.h> 23 #include <fcntl.h> 24 #include <sys/mount.h> 25 #include <unistd.h> 26 27 int main(void) 28 { 29 if (unshare(CLONE_NEWNS) == -1) { 30 if (errno == ENOSYS || errno == EPERM) { 31 fprintf(stderr, "error: unshare, errno %d\n", errno); 32 return 4; 33 } 34 fprintf(stderr, "error: unshare, errno %d\n", errno); 35 return 1; 36 } 37 if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) { 38 fprintf(stderr, "error: mount '/', errno %d\n", errno); 39 return 1; 40 } 41 /* Require "exec" filesystem. */ 42 if (mount(NULL, "/tmp", "ramfs", 0, NULL) == -1) { 43 fprintf(stderr, "error: mount ramfs, errno %d\n", errno); 44 return 1; 45 } 46 47 #define FILENAME "/tmp/1" 48 49 int fd = creat(FILENAME, 0700); 50 if (fd == -1) { 51 fprintf(stderr, "error: creat, errno %d\n", errno); 52 return 1; 53 } 54 #define S "#!" FILENAME "\n" 55 if (write(fd, S, strlen(S)) != strlen(S)) { 56 fprintf(stderr, "error: write, errno %d\n", errno); 57 return 1; 58 } 59 close(fd); 60 61 int rv = execve(FILENAME, NULL, NULL); 62 if (rv == -1 && errno == ELOOP) { 63 return 0; 64 } 65 fprintf(stderr, "error: execve, rv %d, errno %d\n", rv, errno); 66 return 1; 67 } 68