1 files changed, 16 insertions, 0 deletions

diff --git a/security/Kconfig b/security/Kconfig
index d23c839038f0..4c865345caa0 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -113,6 +113,22 @@ config SECURITY_ROOTPLUG
 
           If you are unsure how to answer this question, answer N.
 
+config LSM_MMAP_MIN_ADDR
+        int "Low address space for LSM to protect from user allocation"
+        depends on SECURITY && SECURITY_SELINUX
+        default 65536
+        help
+          This is the portion of low virtual memory which should be protected
+          from userspace allocation.  Keeping a user from writing to low pages
+          can help reduce the impact of kernel NULL pointer bugs.
+
+          For most ia64, ppc64 and x86 users with lots of address space
+          a value of 65536 is reasonable and should cause no problems.
+          On arm and other archs it should not be higher than 32768.
+          Programs which use vm86 functionality or have some need to map
+          this low address space will need the permission specific to the
+          systems running LSM.
+
 source security/selinux/Kconfig
 source security/smack/Kconfig
 source security/tomoyo/Kconfig