Home | History | Annotate | Download | only in speculative 
      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 _GNU_SOURCE 1		/* XXX: Read baloney below about CAP_* */
     16 #define _XOPEN_SOURCE 600
     17 
     18 #include <sys/mman.h>
     19 #include <stdio.h>
     20 #include <unistd.h>
     21 #include <stdlib.h>
     22 #include <errno.h>
     23 #include <sys/types.h>
     24 #include <pwd.h>
     25 #include <string.h>
     26 #include <sys/resource.h>
     27 #include "posixtest.h"
     28 
     29 #define BUFSIZE 8
     30 
     31 /** Set the euid of this process to a non-root uid */
     32 int set_nonroot()
     33 {
     34 	struct passwd *pw;
     35 	struct rlimit rlim;
     36 	int ret = 0;
     37 
     38 	setpwent();
     39 	/* search for the first user which is non root */
     40 	while ((pw = getpwent()) != NULL)
     41 		if (strcmp(pw->pw_name, "root"))
     42 			break;
     43 	endpwent();
     44 	if (pw == NULL) {
     45 		printf("There is no other user than current and root.\n");
     46 		return 1;
     47 	}
     48 
     49 	/*
     50 	 * mlock()
     51 	 * EPERM:
     52 	 * (Linux 2.6.9 and later) the caller was not privileged (CAP_IPC_LOCK)
     53 	 * and its RLIMIT_MEMLOCK soft resource limit was 0.
     54 	 */
     55 
     56 	rlim.rlim_cur = 0;
     57 	rlim.rlim_max = 0;
     58 	if ((ret = setrlimit(RLIMIT_MEMLOCK, &rlim)) != 0)
     59 		printf("Failed at setrlimit() return %d \n", ret);
     60 
     61 	if (seteuid(pw->pw_uid) != 0) {
     62 		if (errno == EPERM) {
     63 			printf
     64 			    ("You don't have permission to change your UID.\n");
     65 			return 1;
     66 		}
     67 		perror("An error occurs when calling seteuid()");
     68 		return 1;
     69 	}
     70 
     71 	printf("Testing with user '%s' (uid: %d)\n",
     72 	       pw->pw_name, (int)geteuid());
     73 	return 0;
     74 }
     75 
     76 int main(void)
     77 {
     78 	int result;
     79 	void *ptr;
     80 
     81 	/* This test should be run under standard user permissions */
     82 	if (getuid() == 0) {
     83 		if (set_nonroot() != 0) {
     84 			printf("Cannot run this test as non-root user\n");
     85 			return PTS_UNTESTED;
     86 		}
     87 	}
     88 
     89 	ptr = malloc(BUFSIZE);
     90 	if (ptr == NULL) {
     91 		printf("Can not allocate memory.\n");
     92 		return PTS_UNRESOLVED;
     93 	}
     94 
     95 	result = mlock(ptr, BUFSIZE);
     96 
     97 	if (result == -1 && errno == EPERM) {
     98 		printf("Test PASSED\n");
     99 		return PTS_PASS;
    100 	} else if (result == 0) {
    101 		printf("You have the right to call mlock\n");
    102 		return PTS_FAIL;
    103 	} else {
    104 		perror("Unexpected error");
    105 		return PTS_UNRESOLVED;
    106 	}
    107 
    108 }
    109