[PATCH 1/2] signal: Have prepare_signal detect coredumps using signal->core_state

In preparation for removing the flag SIGNAL_GROUP_COREDUMP, change
prepare_signal to test signal->core_state instead of the flag
SIGNAL_GROUP_COREDUMP.

Both fields are protected by siglock and both live in signal_struct so
there are no real tradeoffs here, just a change to which field is
being tested.

Link: https://lkml.kernel.org/r/20211213225350.27481-1-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <redacted>
---
 kernel/signal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index 8272cac5f429..f95a4423519d 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c

@@ -906,8 +906,8 @@ static bool prepare_signal(int sig, struct task_struct *p, bool force)
 	struct task_struct *t;
 	sigset_t flush;
 
-	if (signal->flags & (SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP)) {
-		if (!(signal->flags & SIGNAL_GROUP_EXIT))
+	if ((signal->flags & SIGNAL_GROUP_EXIT) || signal->core_state) {
+		if (signal->core_state)
 			return sig == SIGKILL;
 		/*
 		 * The process is in the middle of dying, nothing to do.

-- 
2.29.2