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Diffstat (limited to 'fs/coredump.c')
-rw-r--r--fs/coredump.c88
1 files changed, 11 insertions, 77 deletions
diff --git a/fs/coredump.c b/fs/coredump.c
index 3224dee44d30..a6b3c196cdef 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -359,7 +359,7 @@ static int zap_process(struct task_struct *start, int exit_code, int flags)
for_each_thread(start, t) {
task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
- if (t != current && t->mm) {
+ if (t != current && !(t->flags & PF_POSTCOREDUMP)) {
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
nr++;
@@ -369,99 +369,34 @@ static int zap_process(struct task_struct *start, int exit_code, int flags)
return nr;
}
-static int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
+static int zap_threads(struct task_struct *tsk,
struct core_state *core_state, int exit_code)
{
- struct task_struct *g, *p;
- unsigned long flags;
int nr = -EAGAIN;
spin_lock_irq(&tsk->sighand->siglock);
if (!signal_group_exit(tsk->signal)) {
- mm->core_state = core_state;
+ tsk->signal->core_state = core_state;
tsk->signal->group_exit_task = tsk;
nr = zap_process(tsk, exit_code, 0);
clear_tsk_thread_flag(tsk, TIF_SIGPENDING);
+ tsk->flags |= PF_DUMPCORE;
+ atomic_set(&core_state->nr_threads, nr);
}
spin_unlock_irq(&tsk->sighand->siglock);
- if (unlikely(nr < 0))
- return nr;
-
- tsk->flags |= PF_DUMPCORE;
- if (atomic_read(&mm->mm_users) == nr + 1)
- goto done;
- /*
- * We should find and kill all tasks which use this mm, and we should
- * count them correctly into ->nr_threads. We don't take tasklist
- * lock, but this is safe wrt:
- *
- * fork:
- * None of sub-threads can fork after zap_process(leader). All
- * processes which were created before this point should be
- * visible to zap_threads() because copy_process() adds the new
- * process to the tail of init_task.tasks list, and lock/unlock
- * of ->siglock provides a memory barrier.
- *
- * do_exit:
- * The caller holds mm->mmap_lock. This means that the task which
- * uses this mm can't pass exit_mm(), so it can't exit or clear
- * its ->mm.
- *
- * de_thread:
- * It does list_replace_rcu(&leader->tasks, &current->tasks),
- * we must see either old or new leader, this does not matter.
- * However, it can change p->sighand, so lock_task_sighand(p)
- * must be used. Since p->mm != NULL and we hold ->mmap_lock
- * it can't fail.
- *
- * Note also that "g" can be the old leader with ->mm == NULL
- * and already unhashed and thus removed from ->thread_group.
- * This is OK, __unhash_process()->list_del_rcu() does not
- * clear the ->next pointer, we will find the new leader via
- * next_thread().
- */
- rcu_read_lock();
- for_each_process(g) {
- if (g == tsk->group_leader)
- continue;
- if (g->flags & PF_KTHREAD)
- continue;
-
- for_each_thread(g, p) {
- if (unlikely(!p->mm))
- continue;
- if (unlikely(p->mm == mm)) {
- lock_task_sighand(p, &flags);
- nr += zap_process(p, exit_code,
- SIGNAL_GROUP_EXIT);
- unlock_task_sighand(p, &flags);
- }
- break;
- }
- }
- rcu_read_unlock();
-done:
- atomic_set(&core_state->nr_threads, nr);
return nr;
}
static int coredump_wait(int exit_code, struct core_state *core_state)
{
struct task_struct *tsk = current;
- struct mm_struct *mm = tsk->mm;
int core_waiters = -EBUSY;
init_completion(&core_state->startup);
core_state->dumper.task = tsk;
core_state->dumper.next = NULL;
- if (mmap_write_lock_killable(mm))
- return -EINTR;
-
- if (!mm->core_state)
- core_waiters = zap_threads(tsk, mm, core_state, exit_code);
- mmap_write_unlock(mm);
-
+ core_waiters = zap_threads(tsk, core_state, exit_code);
if (core_waiters > 0) {
struct core_thread *ptr;
@@ -483,7 +418,7 @@ static int coredump_wait(int exit_code, struct core_state *core_state)
return core_waiters;
}
-static void coredump_finish(struct mm_struct *mm, bool core_dumped)
+static void coredump_finish(bool core_dumped)
{
struct core_thread *curr, *next;
struct task_struct *task;
@@ -493,22 +428,21 @@ static void coredump_finish(struct mm_struct *mm, bool core_dumped)
current->signal->group_exit_code |= 0x80;
current->signal->group_exit_task = NULL;
current->signal->flags = SIGNAL_GROUP_EXIT;
+ next = current->signal->core_state->dumper.next;
+ current->signal->core_state = NULL;
spin_unlock_irq(&current->sighand->siglock);
- next = mm->core_state->dumper.next;
while ((curr = next) != NULL) {
next = curr->next;
task = curr->task;
/*
- * see exit_mm(), curr->task must not see
+ * see coredump_task_exit(), curr->task must not see
* ->task == NULL before we read ->next.
*/
smp_mb();
curr->task = NULL;
wake_up_process(task);
}
-
- mm->core_state = NULL;
}
static bool dump_interrupted(void)
@@ -839,7 +773,7 @@ fail_dropcount:
fail_unlock:
kfree(argv);
kfree(cn.corename);
- coredump_finish(mm, core_dumped);
+ coredump_finish(core_dumped);
revert_creds(old_cred);
fail_creds:
put_cred(cred);