signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process

There are only a few places that test SIGNAL_GROUP_EXIT and
are not also already testing SIGNAL_GROUP_COREDUMP.

This will not affect the callers of signal_group_exit as zap_process
also sets group_exit_task so signal_group_exit will continue to return
true at the same times.

This does not affect wait_task_zombie as the none of the threads
wind up in EXIT_ZOMBIE state during a coredump.

This does not affect oom_kill.c:__task_will_free_mem as
sig->core_state is tested and handled before SIGNAL_GROUP_EXIT is
tested for.

This does not affect complete_signal as signal->core_state is tested
for to ensure the coredump case is handled appropriately.

Link: https://lkml.kernel.org/r/20211213225350.27481-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

diff --git a/fs/coredump.c b/fs/coredump.c
index a6b3c19..0864941 100644 (file)
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -347,13 +347,13 @@ out:
        return ispipe;
 }
 
-static int zap_process(struct task_struct *start, int exit_code, int flags)
+static int zap_process(struct task_struct *start, int exit_code)
 {
        struct task_struct *t;
        int nr = 0;
 
        /* ignore all signals except SIGKILL, see prepare_signal() */
-       start->signal->flags = SIGNAL_GROUP_COREDUMP | flags;
+       start->signal->flags = SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP;
        start->signal->group_exit_code = exit_code;
        start->signal->group_stop_count = 0;
 
@@ -378,7 +378,7 @@ static int zap_threads(struct task_struct *tsk,
        if (!signal_group_exit(tsk->signal)) {
                tsk->signal->core_state = core_state;
                tsk->signal->group_exit_task = tsk;
-               nr = zap_process(tsk, exit_code, 0);
+               nr = zap_process(tsk, exit_code);
                clear_tsk_thread_flag(tsk, TIF_SIGPENDING);
                tsk->flags |= PF_DUMPCORE;
                atomic_set(&core_state->nr_threads, nr);