units: further lock down our long-running services

Let's make this an excercise in dogfooding: let's turn on more security features for all our long-running services. Specifically: - Turn on RestrictRealtime=yes for all of them - Turn on ProtectKernelTunables=yes and ProtectControlGroups=yes for most of them - Turn on RestrictAddressFamilies= for all of them, but different sets of address families for each Also, always order settings in the unit files, that the various sandboxing features are close together. Add a couple of missing, older settings for a numbre of unit files. Note that this change turns off AF_INET/AF_INET6 from udevd, thus effectively turning of networking from udev rule commands. Since this might break stuff (that is already broken I'd argue) this is documented in NEWS.
systemd · Sep 25, 2016 · 0c28d51 · 0c28d51
1 parent f6eb19a
commit 0c28d51
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Showing 14 changed files with 71 additions and 19 deletions.
diff --git a/units/systemd-hostnamed.service.in b/units/systemd-hostnamed.service.in
@@ -13,12 +13,16 @@ Documentation=http://www.freedesktop.org/wiki/Software/systemd/hostnamed
 [Service]
 ExecStart=@rootlibexecdir@/systemd-hostnamed
 BusName=org.freedesktop.hostname1
-CapabilityBoundingSet=CAP_SYS_ADMIN
 WatchdogSec=3min
+CapabilityBoundingSet=CAP_SYS_ADMIN
 PrivateTmp=yes
 PrivateDevices=yes
 PrivateNetwork=yes
 ProtectSystem=yes
 ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
diff --git a/units/systemd-importd.service.in b/units/systemd-importd.service.in
@@ -13,9 +13,11 @@ Documentation=http://www.freedesktop.org/wiki/Software/systemd/importd
 [Service]
 ExecStart=@rootlibexecdir@/systemd-importd
 BusName=org.freedesktop.import1
-CapabilityBoundingSet=CAP_CHOWN CAP_FOWNER CAP_FSETID CAP_MKNOD CAP_SETFCAP CAP_SYS_ADMIN CAP_SETPCAP CAP_DAC_OVERRIDE
-NoNewPrivileges=yes
 WatchdogSec=3min
 KillMode=mixed
+CapabilityBoundingSet=CAP_CHOWN CAP_FOWNER CAP_FSETID CAP_MKNOD CAP_SETFCAP CAP_SYS_ADMIN CAP_SETPCAP CAP_DAC_OVERRIDE
+NoNewPrivileges=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @obsolete @raw-io
diff --git a/units/systemd-journal-gatewayd.service.in b/units/systemd-journal-gatewayd.service.in
@@ -20,6 +20,11 @@ PrivateDevices=yes
 PrivateNetwork=yes
 ProtectSystem=full
 ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
+MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 
 # If there are many split upjournal files we need a lot of fds to
 # access them all and combine

diff --git a/units/systemd-journal-remote.service.in b/units/systemd-journal-remote.service.in
@@ -11,15 +11,20 @@ Documentation=man:systemd-journal-remote(8) man:journal-remote.conf(5)
 Requires=systemd-journal-remote.socket
 
 [Service]
-ExecStart=@rootlibexecdir@/systemd-journal-remote \
-          --listen-https=-3 \
-          --output=/var/log/journal/remote/
+ExecStart=@rootlibexecdir@/systemd-journal-remote --listen-https=-3 --output=/var/log/journal/remote/
 User=systemd-journal-remote
 Group=systemd-journal-remote
+WatchdogSec=3min
 PrivateTmp=yes
 PrivateDevices=yes
 PrivateNetwork=yes
-WatchdogSec=3min
+ProtectSystem=full
+ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
+MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 
 [Install]
 Also=systemd-journal-remote.socket
diff --git a/units/systemd-journal-upload.service.in b/units/systemd-journal-upload.service.in
@@ -11,13 +11,19 @@ Documentation=man:systemd-journal-upload(8)
 After=network.target
 
 [Service]
-ExecStart=@rootlibexecdir@/systemd-journal-upload \
-          --save-state
+ExecStart=@rootlibexecdir@/systemd-journal-upload --save-state
 User=systemd-journal-upload
 SupplementaryGroups=systemd-journal
+WatchdogSec=3min
 PrivateTmp=yes
 PrivateDevices=yes
-WatchdogSec=3min
+ProtectSystem=full
+ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
+MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 
 # If there are many split up journal files we need a lot of fds to
 # access them all and combine

diff --git a/units/systemd-journald.service.in b/units/systemd-journald.service.in
@@ -21,10 +21,12 @@ Restart=always
 RestartSec=0
 NotifyAccess=all
 StandardOutput=null
-CapabilityBoundingSet=CAP_SYS_ADMIN CAP_DAC_OVERRIDE CAP_SYS_PTRACE CAP_SYSLOG CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_CHOWN CAP_DAC_READ_SEARCH CAP_FOWNER CAP_SETUID CAP_SETGID CAP_MAC_OVERRIDE
 WatchdogSec=3min
 FileDescriptorStoreMax=1024
+CapabilityBoundingSet=CAP_SYS_ADMIN CAP_DAC_OVERRIDE CAP_SYS_PTRACE CAP_SYSLOG CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_CHOWN CAP_DAC_READ_SEARCH CAP_FOWNER CAP_SETUID CAP_SETGID CAP_MAC_OVERRIDE
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
 
 # Increase the default a bit in order to allow many simultaneous

diff --git a/units/systemd-localed.service.in b/units/systemd-localed.service.in
@@ -13,12 +13,16 @@ Documentation=http://www.freedesktop.org/wiki/Software/systemd/localed
 [Service]
 ExecStart=@rootlibexecdir@/systemd-localed
 BusName=org.freedesktop.locale1
-CapabilityBoundingSet=
 WatchdogSec=3min
+CapabilityBoundingSet=
 PrivateTmp=yes
 PrivateDevices=yes
 PrivateNetwork=yes
 ProtectSystem=yes
 ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
diff --git a/units/systemd-logind.service.in b/units/systemd-logind.service.in
@@ -23,9 +23,11 @@ ExecStart=@rootlibexecdir@/systemd-logind
 Restart=always
 RestartSec=0
 BusName=org.freedesktop.login1
-CapabilityBoundingSet=CAP_SYS_ADMIN CAP_MAC_ADMIN CAP_AUDIT_CONTROL CAP_CHOWN CAP_KILL CAP_DAC_READ_SEARCH CAP_DAC_OVERRIDE CAP_FOWNER CAP_SYS_TTY_CONFIG
 WatchdogSec=3min
+CapabilityBoundingSet=CAP_SYS_ADMIN CAP_MAC_ADMIN CAP_AUDIT_CONTROL CAP_CHOWN CAP_KILL CAP_DAC_READ_SEARCH CAP_DAC_OVERRIDE CAP_FOWNER CAP_SYS_TTY_CONFIG
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @obsolete @raw-io
 
 # Increase the default a bit in order to allow many simultaneous

diff --git a/units/systemd-machined.service.in b/units/systemd-machined.service.in
@@ -15,9 +15,11 @@ After=machine.slice
 [Service]
 ExecStart=@rootlibexecdir@/systemd-machined
 BusName=org.freedesktop.machine1
-CapabilityBoundingSet=CAP_KILL CAP_SYS_PTRACE CAP_SYS_ADMIN CAP_SETGID CAP_SYS_CHROOT CAP_DAC_READ_SEARCH CAP_DAC_OVERRIDE CAP_CHOWN CAP_FOWNER CAP_FSETID CAP_MKNOD
 WatchdogSec=3min
+CapabilityBoundingSet=CAP_KILL CAP_SYS_PTRACE CAP_SYS_ADMIN CAP_SETGID CAP_SYS_CHROOT CAP_DAC_READ_SEARCH CAP_DAC_OVERRIDE CAP_CHOWN CAP_FOWNER CAP_FSETID CAP_MKNOD
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @obsolete @raw-io
 
 # Note that machined cannot be placed in a mount namespace, since it

diff --git a/units/systemd-networkd.service.m4.in b/units/systemd-networkd.service.m4.in
@@ -27,11 +27,14 @@ Type=notify
 Restart=on-failure
 RestartSec=0
 ExecStart=@rootlibexecdir@/systemd-networkd
+WatchdogSec=3min
 CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_BIND_SERVICE CAP_NET_BROADCAST CAP_NET_RAW CAP_SETUID CAP_SETGID CAP_SETPCAP CAP_CHOWN CAP_DAC_OVERRIDE CAP_FOWNER
 ProtectSystem=full
 ProtectHome=yes
-WatchdogSec=3min
+ProtectControlGroups=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6 AF_PACKET
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
 
 [Install]

diff --git a/units/systemd-resolved.service.m4.in b/units/systemd-resolved.service.m4.in
@@ -23,11 +23,17 @@ Type=notify
 Restart=always
 RestartSec=0
 ExecStart=@rootlibexecdir@/systemd-resolved
+WatchdogSec=3min
 CapabilityBoundingSet=CAP_SETUID CAP_SETGID CAP_SETPCAP CAP_CHOWN CAP_DAC_OVERRIDE CAP_FOWNER CAP_NET_RAW CAP_NET_BIND_SERVICE
+PrivateTmp=yes
+PrivateDevices=yes
 ProtectSystem=full
 ProtectHome=yes
-WatchdogSec=3min
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6
 SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
 
 [Install]

diff --git a/units/systemd-timedated.service.in b/units/systemd-timedated.service.in
@@ -13,10 +13,14 @@ Documentation=http://www.freedesktop.org/wiki/Software/systemd/timedated
 [Service]
 ExecStart=@rootlibexecdir@/systemd-timedated
 BusName=org.freedesktop.timedate1
-CapabilityBoundingSet=CAP_SYS_TIME
 WatchdogSec=3min
+CapabilityBoundingSet=CAP_SYS_TIME
 PrivateTmp=yes
 ProtectSystem=yes
 ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX
 SystemCallFilter=~@cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
diff --git a/units/systemd-timesyncd.service.in b/units/systemd-timesyncd.service.in
@@ -22,13 +22,17 @@ Type=notify
 Restart=always
 RestartSec=0
 ExecStart=@rootlibexecdir@/systemd-timesyncd
+WatchdogSec=3min
 CapabilityBoundingSet=CAP_SYS_TIME CAP_SETUID CAP_SETGID CAP_SETPCAP CAP_CHOWN CAP_DAC_OVERRIDE CAP_FOWNER
 PrivateTmp=yes
 PrivateDevices=yes
 ProtectSystem=full
 ProtectHome=yes
-WatchdogSec=3min
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
 MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 SystemCallFilter=~@cpu-emulation @debug @keyring @module @mount @obsolete @raw-io
 
 [Install]

diff --git a/units/systemd-udevd.service.in b/units/systemd-udevd.service.in
@@ -21,7 +21,10 @@ Sockets=systemd-udevd-control.socket systemd-udevd-kernel.socket
 Restart=always
 RestartSec=0
 ExecStart=@rootlibexecdir@/systemd-udevd
-MountFlags=slave
 KillMode=mixed
 WatchdogSec=3min
 TasksMax=infinity
+MountFlags=slave
+MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_NETLINK