sysctl: enable coredump for suid binaries

NEWS

@@ -1,5 +1,11 @@
 systemd System and Service Manager
 
+CHANGES WITH 246 in spe:
+        * The fs.suid_dumpable sysctl is set to 2 / "suidsafe". This allows
+          systemd-coredump to save core files for suid processes. When saving
+          the core file, systemd-coredump will use the effective uid and gid of
+          the process that faulted.
+
 CHANGES WITH 245:
 
         * A new tool "systemd-repart" has been added, that operates as an

sysctl.d/50-coredump.conf.in

@@ -5,8 +5,23 @@
 #  the Free Software Foundation; either version 2.1 of the License, or
 #  (at your option) any later version.
 
-# See sysctl.d(5) for the description of the files in this directory,
-# and systemd-coredump(8) and core(5) for the explanation of the
-# setting below.
+# See sysctl.d(5) for the description of the files in this directory.
 
+# Pipe the core file to systemd-coredump. The systemd-coredump process spawned
+# by the kernel will start a second copy of itself as the
+# systemd-coredump@.service, which will do the actual processing and storing of
+# the core dump.
+#
+# See systemd-coredump(8) and core(5).
 kernel.core_pattern=|@rootlibexecdir@/systemd-coredump %P %u %g %s %t %c %h
+
+# Also dump processes executing a set-user-ID/set-group-ID program that is
+# owned by a user/group other than the real user/group ID of the process, or
+# a program that has file capabilities. ("2" is called "suidsafe" in core(5)).
+#
+# systemd-coredump will store the core file owned by the effective uid and gid
+# of the running process (and not the filesystem-user-ID which the kernel uses
+# when saving a core dump).
+#
+# See proc(5), setuid(2), capabilities(7).
+fs.suid_dumpable=2