| /* |
| * Copyright (c) 2017 Fujitsu Ltd. |
| * Ported: Guangwen Feng <fenggw-fnst@cn.fujitsu.com> |
| * |
| * This program is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program, if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| /* |
| * This is a regression test for the race between keyctl_read() and |
| * keyctl_revoke(), if the revoke happens between keyctl_read() |
| * checking the validity of a key and the key's semaphore being taken, |
| * then the key type read method will see a revoked key. |
| * |
| * This causes a problem for the user-defined key type because it |
| * assumes in its read method that there will always be a payload |
| * in a non-revoked key and doesn't check for a NULL pointer. |
| * |
| * This test can crash the buggy kernel, and the bug was fixed in: |
| * |
| * commit b4a1b4f5047e4f54e194681125c74c0aa64d637d |
| * Author: David Howells <dhowells@redhat.com> |
| * Date: Fri Dec 18 01:34:26 2015 +0000 |
| * |
| * KEYS: Fix race between read and revoke |
| */ |
| |
| #include "config.h" |
| #include <errno.h> |
| #include <pthread.h> |
| #include <sys/types.h> |
| #ifdef HAVE_KEYUTILS_H |
| # include <keyutils.h> |
| #endif |
| #include "tst_safe_pthread.h" |
| #include "tst_test.h" |
| |
| #ifdef HAVE_KEYUTILS_H |
| |
| #define LOOPS 20000 |
| |
| static void *do_read(void *arg) |
| { |
| key_serial_t key = (unsigned long)arg; |
| char buffer[4] = { 0 }; |
| |
| keyctl(KEYCTL_READ, key, buffer, 4); |
| |
| return NULL; |
| } |
| |
| static void *do_revoke(void *arg) |
| { |
| key_serial_t key = (unsigned long)arg; |
| |
| keyctl(KEYCTL_REVOKE, key); |
| |
| return NULL; |
| } |
| |
| static void do_test(void) |
| { |
| int i; |
| key_serial_t key; |
| pthread_t pth[4]; |
| |
| for (i = 0; i < LOOPS; i++) { |
| key = add_key("user", "ltptestkey", "foo", 3, |
| KEY_SPEC_PROCESS_KEYRING); |
| if (key == -1) |
| tst_brk(TBROK, "Failed to add key"); |
| |
| SAFE_PTHREAD_CREATE(&pth[0], NULL, do_read, |
| (void *)(unsigned long)key); |
| SAFE_PTHREAD_CREATE(&pth[1], NULL, do_revoke, |
| (void *)(unsigned long)key); |
| SAFE_PTHREAD_CREATE(&pth[2], NULL, do_read, |
| (void *)(unsigned long)key); |
| SAFE_PTHREAD_CREATE(&pth[3], NULL, do_revoke, |
| (void *)(unsigned long)key); |
| |
| SAFE_PTHREAD_JOIN(pth[0], NULL); |
| SAFE_PTHREAD_JOIN(pth[1], NULL); |
| SAFE_PTHREAD_JOIN(pth[2], NULL); |
| SAFE_PTHREAD_JOIN(pth[3], NULL); |
| } |
| |
| tst_res(TPASS, "Bug not reproduced"); |
| } |
| |
| static struct tst_test test = { |
| .tid = "keyctl02", |
| .test_all = do_test, |
| }; |
| |
| #else |
| TST_TEST_TCONF("keyutils.h does not exist"); |
| #endif /* HAVE_KEYUTILS_H */ |