From: Eric W. Biederman <ebiederm@xmission.com>
Date: Fri, 20 Jul 2018 21:35:14 +0000 (-0500)
Subject: signal: Use group_send_sig_info to kill all processes in a pid namespace
X-Git-Tag: v5.4-rc1~2401^2~67
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=82058d6684658430cd9b4123d4c3e863fd48f813;p=platform%2Fkernel%2Flinux-rpi.git

signal: Use group_send_sig_info to kill all processes in a pid namespace

Replace send_sig_info in zap_pid_ns_processes with
group_send_sig_info.  This makes more sense as the entire process
group is being killed.  More importantly this allows the kill of those
processes with PIDTYPE_MAX to indicate all of the process in the pid
namespace are being signaled.  This is needed for fork to detect when
signals are sent to a group of processes.

Admittedly fork has another case to catch SIGKILL but the principle remains
that it is desirable to know when a group of processes is being signaled.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---

diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index c8d5339..aa6e72f 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -216,7 +216,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 	idr_for_each_entry_continue(&pid_ns->idr, pid, nr) {
 		task = pid_task(pid, PIDTYPE_PID);
 		if (task && !__fatal_signal_pending(task))
-			send_sig_info(SIGKILL, SEND_SIG_PRIV, task);
+			group_send_sig_info(SIGKILL, SEND_SIG_PRIV, task, PIDTYPE_MAX);
 	}
 	read_unlock(&tasklist_lock);
 	rcu_read_unlock();