diff options
| -rw-r--r-- | kernel/exit.c | 3 | ||||
| -rw-r--r-- | kernel/seccomp.c | 23 |
2 files changed, 20 insertions, 6 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index f95a2c1338a8..b945ab81eb92 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -277,7 +277,6 @@ repeat: } write_unlock_irq(&tasklist_lock); - seccomp_filter_release(p); proc_flush_pid(thread_pid); put_pid(thread_pid); release_thread(p); @@ -832,6 +831,8 @@ void __noreturn do_exit(long code) io_uring_files_cancel(); exit_signals(tsk); /* sets PF_EXITING */ + seccomp_filter_release(tsk); + acct_update_integrals(tsk); group_dead = atomic_dec_and_test(&tsk->signal->live); if (group_dead) { diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 60990264fef0..dc51e521bc1d 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -502,6 +502,9 @@ static inline pid_t seccomp_can_sync_threads(void) /* Skip current, since it is initiating the sync. */ if (thread == caller) continue; + /* Skip exited threads. */ + if (thread->flags & PF_EXITING) + continue; if (thread->seccomp.mode == SECCOMP_MODE_DISABLED || (thread->seccomp.mode == SECCOMP_MODE_FILTER && @@ -563,18 +566,21 @@ static void __seccomp_filter_release(struct seccomp_filter *orig) * @tsk: task the filter should be released from. * * This function should only be called when the task is exiting as - * it detaches it from its filter tree. As such, READ_ONCE() and - * barriers are not needed here, as would normally be needed. + * it detaches it from its filter tree. PF_EXITING has to be set + * for the task. */ void seccomp_filter_release(struct task_struct *tsk) { - struct seccomp_filter *orig = tsk->seccomp.filter; + struct seccomp_filter *orig; - /* We are effectively holding the siglock by not having any sighand. */ - WARN_ON(tsk->sighand != NULL); + if (WARN_ON((tsk->flags & PF_EXITING) == 0)) + return; + spin_lock_irq(&tsk->sighand->siglock); + orig = tsk->seccomp.filter; /* Detach task from its filter tree. */ tsk->seccomp.filter = NULL; + spin_unlock_irq(&tsk->sighand->siglock); __seccomp_filter_release(orig); } @@ -602,6 +608,13 @@ static inline void seccomp_sync_threads(unsigned long flags) if (thread == caller) continue; + /* + * Skip exited threads. seccomp_filter_release could have + * been already called for this task. + */ + if (thread->flags & PF_EXITING) + continue; + /* Get a task reference for the new leaf node. */ get_seccomp_filter(caller); |