From:   "Eric W. Biederman" <ebiederm@xmission.com>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-api@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Alexey Gladkov <legion@kernel.org>,
        Kyle Huey <me@kylehuey.com>, Oleg Nesterov <oleg@redhat.com>,
        Kees Cook <keescook@chromium.org>,
        Al Viro <viro@ZenIV.linux.org.uk>
References: <87a6ha4zsd.fsf@email.froward.int.ebiederm.org>
        <20211213225350.27481-1-ebiederm@xmission.com>
        <9363765f-9883-75ee-70f1-a1a8e9841812@gmail.com>
        <87pmp67y4r.fsf@email.froward.int.ebiederm.org>
        <5bbb54c4-7504-cd28-5dde-4e5965496625@gmail.com>
        <87bl0m14ew.fsf@email.froward.int.ebiederm.org>
Date:   Sat, 08 Jan 2022 12:15:19 -0600
In-Reply-To: <87bl0m14ew.fsf@email.froward.int.ebiederm.org> (Eric
        W. Biederman's message of "Sat, 08 Jan 2022 12:13:59 -0600")
Message-ID: <875yqu14co.fsf_-_@email.froward.int.ebiederm.org>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux)
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Subject: [PATCH 1/2] signal: Have prepare_signal detect coredumps using
 signal->core_state
Precedence: bulk


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" <ebiederm@xmission.com>
---
 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