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malloc/tst-mallocfork2: Kill lingering process for unexpected failures

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If the test fails due some unexpected failure after the children
creation, either in the signal handler by calling abort or in the main
loop; the created children might not be killed properly.

This patches fixes it by:

  * Avoid aborting in the signal handler by setting a flag that
    an error has occured and add a check in the main loop.

  * Add a atexit handler to handle kill child processes.

Checked on x86_64-linux-gnu.
This commit is contained in:
Adhemerval Zanella 2020-02-20 14:37:04 -03:00
parent 758599bc9d
commit 5c8aa3849a
1 changed files with 28 additions and 11 deletions
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39
malloc/tst-mallocfork2.c
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@ -62,6 +62,9 @@ static volatile sig_atomic_t sigusr1_received;
progress. Checked by liveness_signal_handler. */
static volatile sig_atomic_t progress_indicator = 1;
/* Set to 1 if an error occurs in the signal handler. */
static volatile sig_atomic_t error_indicator = 0;
static void
sigusr1_handler (int signo)
{
@ -72,7 +75,8 @@ sigusr1_handler (int signo)
if (pid == -1)
{
write_message ("error: fork\n");
abort ();
error_indicator = 1;
return;
}
if (pid == 0)
_exit (0);
@ -81,12 +85,14 @@ sigusr1_handler (int signo)
if (ret < 0)
{
write_message ("error: waitpid\n");
abort ();
error_indicator = 1;
return;
}
if (status != 0)
{
write_message ("error: unexpected exit status from subprocess\n");
abort ();
error_indicator = 1;
return;
}
}
@ -122,9 +128,25 @@ signal_sender (int signo, bool sleep)
}
}
/* Children processes. */
static pid_t sigusr1_sender_pids[5] = { 0 };
static pid_t sigusr2_sender_pid = 0;
static void
kill_children (void)
{
for (size_t i = 0; i < array_length (sigusr1_sender_pids); ++i)
if (sigusr1_sender_pids[i] > 0)
kill (sigusr1_sender_pids[i], SIGKILL);
if (sigusr2_sender_pid > 0)
kill (sigusr2_sender_pid, SIGKILL);
}
static int
do_test (void)
{
atexit (kill_children);
/* shared->barrier is intialized along with sigusr1_sender_pids
below. */
shared = support_shared_allocate (sizeof (*shared));
@ -148,14 +170,13 @@ do_test (void)
return 1;
}
pid_t sigusr2_sender_pid = xfork ();
sigusr2_sender_pid = xfork ();
if (sigusr2_sender_pid == 0)
signal_sender (SIGUSR2, true);
/* Send SIGUSR1 signals from several processes. Hopefully, one
signal will hit one of the ciritical functions. Use a barrier to
avoid sending signals while not running fork/free/malloc. */
pid_t sigusr1_sender_pids[5];
{
pthread_barrierattr_t attr;
xpthread_barrierattr_init (&attr);
@ -166,7 +187,7 @@ do_test (void)
}
for (size_t i = 0; i < array_length (sigusr1_sender_pids); ++i)
{
sigusr1_sender_pids[i] = fork ();
sigusr1_sender_pids[i] = xfork ();
if (sigusr1_sender_pids[i] == 0)
signal_sender (SIGUSR1, false);
}
@ -211,7 +232,7 @@ do_test (void)
++malloc_signals;
xpthread_barrier_wait (&shared->barrier);
if (objects[slot] == NULL)
if (objects[slot] == NULL || error_indicator != 0)
{
printf ("error: malloc: %m\n");
for (size_t i = 0; i < array_length (sigusr1_sender_pids); ++i)
@ -225,10 +246,6 @@ do_test (void)
for (int slot = 0; slot < malloc_objects; ++slot)
free (objects[slot]);
for (size_t i = 0; i < array_length (sigusr1_sender_pids); ++i)
kill (sigusr1_sender_pids[i], SIGKILL);
kill (sigusr2_sender_pid, SIGKILL);
printf ("info: signals received during fork: %u\n", fork_signals);
printf ("info: signals received during free: %u\n", free_signals);
printf ("info: signals received during malloc: %u\n", malloc_signals);