1  /*
       2   * Check for PTRACE_EVENT_EXEC diagnostics.
       3   *
       4   * Copyright (c) 2019 Dmitry V. Levin <ldv@strace.io>
       5   * Copyright (c) 2019-2020 The strace developers.
       6   * All rights reserved.
       7   *
       8   * SPDX-License-Identifier: GPL-2.0-or-later
       9   */
      10  
      11  #include "tests.h"
      12  #include <errno.h>
      13  #include <pthread.h>
      14  #include <stdio.h>
      15  #include <unistd.h>
      16  #include "scno.h"
      17  
      18  #ifndef QUIET_MSG
      19  # define QUIET_MSG 0
      20  #endif
      21  
      22  static pid_t leader;
      23  static volatile unsigned int trigger;
      24  
      25  static void *
      26  thread(void *arg)
      27  {
      28  	const char *argv[] = {((char **) arg)[0], "1", "2", NULL};
      29  	int tid = syscall(__NR_gettid);
      30  
      31  	printf("%-5d execveat(AT_FDCWD, \"%s\", [\"%s\", \"%s\", \"%s\"]"
      32  	       ", NULL, 0 <pid changed to %d ...>\n"
      33  #if !QUIET_MSG
      34  	       "%-5d +++ superseded by execve in pid %d +++\n"
      35  #endif
      36  	       , tid, argv[0], argv[0], argv[1], argv[2], leader
      37  #if !QUIET_MSG
      38  	       , leader, tid
      39  #endif
      40  	       );
      41  
      42  	while (!trigger) {
      43  		/* Wait for the parent to enter the busy loop.  */
      44  	}
      45  
      46  	syscall(__NR_execveat, -100, argv[0], argv, NULL, 0);
      47  	perror_msg_and_fail("execveat");
      48  }
      49  
      50  int
      51  main(int ac, char **av)
      52  {
      53  	setvbuf(stdout, NULL, _IONBF, 0);
      54  	leader = getpid();
      55  
      56  	if (ac <= 1) {
      57  		char *argv[] = {av[0], (char *) "1", NULL};
      58  		printf("%-5d execveat(AT_FDCWD, \"%s\""
      59  		       ", [\"%s\", \"%s\"], NULL, 0) = 0\n",
      60  		       leader, argv[0], argv[0], argv[1]);
      61  		syscall(__NR_execveat, -100, argv[0], argv, NULL, 0);
      62  		perror_msg_and_skip("execveat");
      63  	}
      64  
      65  	/*
      66  	 * Since execveat is supported by the kernel,
      67  	 * PTRACE_EVENT_EXEC support in the kernel is good enough.
      68  	 */
      69  	if (ac <= 2) {
      70  		pthread_t t;
      71  		errno = pthread_create(&t, NULL, thread, av);
      72  		if (errno)
      73  			perror_msg_and_fail("pthread_create");
      74  
      75  		for (;;)
      76  			++trigger;
      77  	}
      78  
      79  	printf("%-5d <... execveat resumed>) = 0\n"
      80  	       "%-5d +++ exited with 0 +++\n",
      81  	       leader, leader);
      82  	return 0;
      83  }