From d80f7d7b2c75c5954d335dffbccca62a5002c3e0 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 21 Jun 2022 14:38:52 -0500 Subject: signal: Guarantee that SIGNAL_GROUP_EXIT is set on process exit Track how many threads have not started exiting and when the last thread starts exiting set SIGNAL_GROUP_EXIT. This guarantees that SIGNAL_GROUP_EXIT will get set when a process exits. In practice this achieves nothing as glibc's implementation of _exit calls sys_group_exit then sys_exit. While glibc's implemenation of pthread_exit calls exit (which cleansup and calls _exit) if it is the last thread and sys_exit if it is the last thread. This means the only way the kernel might observe a process that does not set call exit_group is if the language runtime does not use glibc. With more cleanups I hope to move the decrement of quick_threads earlier. Link: https://lkml.kernel.org/r/87bkukd4tc.fsf_-_@email.froward.int.ebiederm.org Signed-off-by: "Eric W. Biederman" --- include/linux/sched/signal.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index cafbe03eed01..20099268fa25 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -94,6 +94,7 @@ struct signal_struct { refcount_t sigcnt; atomic_t live; int nr_threads; + int quick_threads; struct list_head thread_head; wait_queue_head_t wait_chldexit; /* for wait4() */ -- cgit v1.2.3