From 9ce1759311c6734deb69aa7253bf7297536a55d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Kl=C3=B6tzke?= <Jan.Kloetzke@preh.de>
Date: Wed, 10 Jan 2018 10:36:14 +0100
Subject: [PATCH 1/2] tree-wide: introduce disable_core_dumps helper and port
 existing users

Changes the core_pattern to prevent any core dumps by the kernel. Does
nothing if we're in a container environment as this is system wide
setting.
---
 src/basic/util.c        | 7 +++++++
 src/basic/util.h        | 2 ++
 src/core/main.c         | 3 ++-
 src/coredump/coredump.c | 2 +-
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/basic/util.c b/src/basic/util.c
index 2a39ff2b538..b1e6f5002ef 100644
--- a/src/basic/util.c
+++ b/src/basic/util.c
@@ -61,6 +61,7 @@
 #include "umask-util.h"
 #include "user-util.h"
 #include "util.h"
+#include "virt.h"
 
 int saved_argc = 0;
 char **saved_argv = NULL;
@@ -615,3 +616,9 @@ int str_verscmp(const char *s1, const char *s2) {
 
         return strcmp(os1, os2);
 }
+
+/* Turn off core dumps but only if we're running outside of a container. */
+void disable_core_dumps(void) {
+        if (detect_container() <= 0)
+                (void) write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", 0);
+}
diff --git a/src/basic/util.h b/src/basic/util.h
index 20181ab9170..c10cfea9523 100644
--- a/src/basic/util.h
+++ b/src/basic/util.h
@@ -191,3 +191,5 @@ int update_reboot_parameter_and_warn(const char *param);
 int version(void);
 
 int str_verscmp(const char *s1, const char *s2);
+
+void disable_core_dumps(void);
diff --git a/src/core/main.c b/src/core/main.c
index 63533dbe101..ef7d7f58dc4 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -91,6 +91,7 @@
 #include "terminal-util.h"
 #include "umask-util.h"
 #include "user-util.h"
+#include "util.h"
 #include "virt.h"
 #include "watchdog.h"
 
@@ -1603,7 +1604,7 @@ static void initialize_coredump(bool skip_setup) {
         /* But at the same time, turn off the core_pattern logic by default, so that no coredumps are stored
          * until the systemd-coredump tool is enabled via sysctl. */
         if (!skip_setup)
-                (void) write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", 0);
+                disable_core_dumps();
 }
 
 static void do_reexecute(
diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c
index e6063cc980e..f83a951df70 100644
--- a/src/coredump/coredump.c
+++ b/src/coredump/coredump.c
@@ -1126,7 +1126,7 @@ static int gather_pid_metadata(
                 /* If this is PID 1 disable coredump collection, we'll unlikely be able to process it later on. */
                 if (is_pid1_crash((const char**) context)) {
                         log_notice("Due to PID 1 having crashed coredump collection will now be turned off.");
-                        (void) write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", 0);
+                        disable_core_dumps();
                 }
 
                 set_iovec_field(iovec, n_iovec, "COREDUMP_UNIT=", context[CONTEXT_UNIT]);

From 27b372c1c2cf634b865a70586cbb38f1acc772d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Kl=C3=B6tzke?= <Jan.Kloetzke@preh.de>
Date: Mon, 23 Oct 2017 08:57:09 +0200
Subject: [PATCH 2/2] shutdown: prevent core dumps in final shutdown stage

If the system is finally shutting down it makes no sense to write core
dumps as the last remaining processes are terminated / killed. This is
especially significant in case of a "force reboot" where all processes
are hit concurrently with a SIGTERM and no orderly shutdown of
processes takes place.
---
 src/core/shutdown.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/core/shutdown.c b/src/core/shutdown.c
index ffab4de1013..b1f581b5482 100644
--- a/src/core/shutdown.c
+++ b/src/core/shutdown.c
@@ -323,6 +323,9 @@ int main(int argc, char *argv[]) {
         if (!in_container)
                 sync_with_progress();
 
+        /* Prevent coredumps */
+        disable_core_dumps();
+
         log_info("Sending SIGTERM to remaining processes...");
         broadcast_signal(SIGTERM, true, true);