1/* 2* Copyright (c) International Business Machines Corp., 2007 3* This program is free software; you can redistribute it and/or modify 4* it under the terms of the GNU General Public License as published by 5* the Free Software Foundation; either version 2 of the License, or 6* (at your option) any later version. 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 10* the GNU General Public License for more details. 11* You should have received a copy of the GNU General Public License 12* along with this program; if not, write to the Free Software 13* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 14* 15*************************************************************************** 16* File: pidns20.c 17* * 18* * Description: 19* * The pidns20.c testcase verifies that signal handler of SIGUSR1 is called 20* * (and cinit is NOT terminated) when: 21* * - container-init blocks SIGUSR1, 22* * - parent queues SIGUSR1 and 23* * - a handler is specified for SIGUSR1 before it is unblocked. 24* * 25* * Test Assertion & Strategy: 26* * Create a PID namespace container. 27* * Block SIGUSR1 signal inside it. 28* * Let parent to deliver SIGUSR1 signal to container. 29* * Redefine SIGUSR1 handler of cinit to user function. 30* * Unblock SIGUSR1 from blocked queue. 31* * Check if user function is called. 32* * 33* * Usage: <for command-line> 34* * pidns20 35* * 36* * History: 37* * DATE NAME DESCRIPTION 38* * 13/11/08 Gowrishankar M Creation of this test. 39* * <gowrishankar.m@in.ibm.com> 40* 41******************************************************************************/ 42#define _GNU_SOURCE 1 43#include <sys/wait.h> 44#include <sys/types.h> 45#include <signal.h> 46#include <stdlib.h> 47#include <unistd.h> 48#include <stdio.h> 49#include "pidns_helper.h" 50#include "test.h" 51#include "safe_macros.h" 52 53char *TCID = "pidns20"; 54int TST_TOTAL = 1; 55 56int parent_cinit[2]; 57int cinit_parent[2]; 58int broken = 1; /* broken should be 0 when test completes properly */ 59 60#define CHILD_PID 1 61#define PARENT_PID 0 62 63/* 64 * child_signal_handler() - to handle SIGUSR1 65 */ 66static void child_signal_handler(int sig, siginfo_t * si, void *unused) 67{ 68 if (si->si_signo != SIGUSR1) 69 tst_resm(TBROK, "cinit: recieved %s unexpectedly!", 70 strsignal(si->si_signo)); 71 else 72 tst_resm(TPASS, "cinit: user function is called as expected"); 73 74 /* Disable broken flag */ 75 broken = 0; 76} 77 78/* 79 * child_fn() - Inside container 80 */ 81int child_fn(void *arg) 82{ 83 pid_t pid, ppid; 84 sigset_t newset; 85 struct sigaction sa; 86 char buf[5]; 87 88 /* Setup pipe read and write ends */ 89 pid = getpid(); 90 ppid = getppid(); 91 92 if (pid != CHILD_PID || ppid != PARENT_PID) { 93 printf("cinit: pidns was not created properly\n"); 94 exit(1); 95 } 96 97 /* Setup pipes to communicate with parent */ 98 close(cinit_parent[0]); 99 close(parent_cinit[1]); 100 101 /* Block SIGUSR1 signal */ 102 sigemptyset(&newset); 103 sigaddset(&newset, SIGUSR1); 104 if (sigprocmask(SIG_BLOCK, &newset, 0) == -1) { 105 perror("cinit: sigprocmask() failed"); 106 exit(1); 107 } 108 tst_resm(TINFO, "cinit: blocked SIGUSR1"); 109 110 /* Let parent to queue SIGUSR1 in pending */ 111 if (write(cinit_parent[1], "c:go", 5) != 5) { 112 perror("cinit: pipe is broken to write"); 113 exit(1); 114 } 115 116 /* Check if parent has queued up SIGUSR1 */ 117 read(parent_cinit[0], buf, 5); 118 if (strcmp(buf, "p:go") != 0) { 119 printf("cinit: parent did not respond!\n"); 120 exit(1); 121 } 122 123 /* Now redefine handler for SIGUSR1 */ 124 sa.sa_flags = SA_SIGINFO; 125 sigfillset(&sa.sa_mask); 126 sa.sa_sigaction = child_signal_handler; 127 if (sigaction(SIGUSR1, &sa, NULL) == -1) { 128 perror("cinit: sigaction failed"); 129 exit(1); 130 } 131 132 /* Unblock traffic on SIGUSR1 queue */ 133 tst_resm(TINFO, "cinit: unblocking SIGUSR1"); 134 sigprocmask(SIG_UNBLOCK, &newset, 0); 135 136 /* Check if new handler is called */ 137 if (broken == 1) { 138 printf("cinit: broken flag didn't change\n"); 139 exit(1); 140 } 141 142 /* Cleanup and exit */ 143 close(cinit_parent[1]); 144 close(parent_cinit[0]); 145 exit(0); 146} 147 148static void setup(void) 149{ 150 tst_require_root(); 151 check_newpid(); 152} 153 154int main(int argc, char *argv[]) 155{ 156 int status; 157 char buf[5]; 158 pid_t cpid; 159 160 setup(); 161 162 /* Create pipes for intercommunication */ 163 if (pipe(parent_cinit) == -1 || pipe(cinit_parent) == -1) { 164 tst_brkm(TBROK | TERRNO, NULL, "pipe failed"); 165 } 166 167 cpid = ltp_clone_quick(CLONE_NEWPID | SIGCHLD, child_fn, NULL); 168 if (cpid == -1) { 169 tst_brkm(TBROK | TERRNO, NULL, "clone failed"); 170 } 171 172 /* Setup pipe read and write ends */ 173 close(cinit_parent[1]); 174 close(parent_cinit[0]); 175 176 /* Is container ready */ 177 read(cinit_parent[0], buf, 5); 178 if (strcmp(buf, "c:go") != 0) { 179 tst_brkm(TBROK, NULL, "parent: container did not respond!"); 180 } 181 182 /* Enqueue SIGUSR1 in pending signal queue of container */ 183 SAFE_KILL(NULL, cpid, SIGUSR1); 184 185 tst_resm(TINFO, "parent: signalled SIGUSR1 to container"); 186 if (write(parent_cinit[1], "p:go", 5) != 5) { 187 tst_brkm(TBROK | TERRNO, NULL, "write failed"); 188 } 189 190 /* collect exit status of child */ 191 SAFE_WAIT(NULL, &status); 192 193 if (WIFSIGNALED(status)) { 194 if (WTERMSIG(status) == SIGUSR1) 195 tst_resm(TFAIL, 196 "user function was not called inside cinit"); 197 else 198 tst_resm(TBROK, 199 "cinit was terminated by %d", 200 WTERMSIG(status)); 201 } 202 203 /* Cleanup and exit */ 204 close(parent_cinit[1]); 205 close(cinit_parent[0]); 206 tst_exit(); 207} 208