From acc28e2e3037d689d6481e4664925cf31d4d087b Mon Sep 17 00:00:00 2001

From: Franck Bui <fbui@suse.com>

Date: Thu, 24 Nov 2016 18:52:04 +0100

Subject: [PATCH] core: make sure initrd-switch-root command survives PID1's

 killing spree (#4730)

This is a different way to implement the fix proposed by commit

a4021390fef27f4136497328f suggested by Lennart Poettering.

In this patch we instruct PID1 to not kill "systemctl switch-root" command

started by initrd-switch-root service using the "argv[0][0]='@'" trick.

See: https://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons/ for

more details.

We had to backup argv[0] because argv is modified by dispatch_verb().

---

 src/systemctl/systemctl.c           | 10 ++++++++++

 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c

index 4fd8d7ba2..ed1c7178b 100644

--- a/src/systemctl/systemctl.c

+++ b/src/systemctl/systemctl.c

@@ -142,6 +142,7 @@ static const char *arg_kill_who = NULL;

 static int arg_signal = SIGTERM;

 static char *arg_root = NULL;

 static usec_t arg_when = 0;

+static char *argv_cmdline = NULL;

 static enum action {

         _ACTION_INVALID,

         ACTION_SYSTEMCTL,

@@ -5638,6 +5639,13 @@ static int switch_root(int argc, char *argv[], void *userdata) {

                         init = NULL;

         }

+        /* Instruct PID1 to exclude us from its killing spree applied during

+         * the transition from the initrd to the main system otherwise we would

+         * exit with a failure status even though the switch to the new root

+         * has succeed. */

+        if (in_initrd())

+                argv_cmdline[0] = '@';

+

         r = acquire_bus(BUS_MANAGER, &bus;;

         if (r < 0)

                 return r;

@@ -8373,6 +8381,8 @@ static int logind_cancel_shutdown(void) {

 int main(int argc, char*argv[]) {

         int r;

+        argv_cmdline = argv[0];

+

         setlocale(LC_ALL, "");

         log_parse_environment();

         log_open();

-- 

2.11.0