divestos-build/Patches/LineageOS-15.1/android_system_core/0001-Harden.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Daniel Micay <danielmicay@gmail.com>
Date: Mon, 12 Feb 2018 03:29:58 -0500
Subject: [PATCH] Harden

Change-Id: I46e3fc4ac896a509ab8ca90ae4ce09b820da434b
[tad@spotco.us]: added protected fifos and regular from newer GrapheneOS patches
[tad@spotco.us]: added IPv6 privacy options TODO split into another patch
---
 init/init.cpp   |  6 +++---
 rootdir/init.rc | 11 +++++++++++
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/init/init.cpp b/init/init.cpp
index 35fc442d0..b65686f93 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -1019,14 +1019,14 @@ int main(int argc, char** argv) {
         mount("tmpfs", "/dev", "tmpfs", MS_NOSUID, "mode=0755");
         mkdir("/dev/pts", 0755);
         mkdir("/dev/socket", 0755);
-        mount("devpts", "/dev/pts", "devpts", 0, NULL);
+        mount("devpts", "/dev/pts", "devpts", MS_NOSUID|MS_NOEXEC, NULL);
         #define MAKE_STR(x) __STRING(x)
-        mount("proc", "/proc", "proc", 0, "hidepid=2,gid=" MAKE_STR(AID_READPROC));
+        mount("proc", "/proc", "proc", MS_NOSUID|MS_NODEV|MS_NOEXEC, "hidepid=2,gid=" MAKE_STR(AID_READPROC));
         // Don't expose the raw commandline to unprivileged processes.
         chmod("/proc/cmdline", 0440);
         gid_t groups[] = { AID_READPROC };
         setgroups(arraysize(groups), groups);
-        mount("sysfs", "/sys", "sysfs", 0, NULL);
+        mount("sysfs", "/sys", "sysfs", MS_NOSUID|MS_NODEV|MS_NOEXEC, NULL);
         mount("selinuxfs", "/sys/fs/selinux", "selinuxfs", 0, NULL);
         mknod("/dev/kmsg", S_IFCHR | 0600, makedev(1, 11));
         mknod("/dev/random", S_IFCHR | 0666, makedev(1, 8));
diff --git a/rootdir/init.rc b/rootdir/init.rc
index f9cb4a3ef..7d618af63 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -124,6 +124,17 @@ on init
     write /proc/sys/kernel/sched_wakeup_granularity_ns 2000000
     write /proc/sys/kernel/sched_child_runs_first 0
 
+    write /proc/sys/kernel/dmesg_restrict 1
+    write /proc/sys/fs/protected_hardlinks 1
+    write /proc/sys/fs/protected_symlinks 1
+    write /proc/sys/fs/protected_fifos 1
+    write /proc/sys/fs/protected_regular 1
+    write /proc/sys/net/ipv6/conf/all/use_tempaddr 2
+    write /proc/sys/net/ipv6/conf/all/max_addresses 128
+    write /proc/sys/net/ipv6/conf/all/temp_prefered_lft 21600
+    write /proc/sys/net/ipv6/conf/default/use_tempaddr 2
+    write /proc/sys/net/ipv6/conf/default/max_addresses 128
+    write /proc/sys/net/ipv6/conf/default/temp_prefered_lft 21600
     write /proc/sys/kernel/randomize_va_space 2
     write /proc/sys/vm/mmap_min_addr 32768
     write /proc/sys/net/ipv4/ping_group_range "0 2147483647"