Merge commit 'v2.6.31-rc8' into x86/txt

[linux-2.6.git] / security / Kconfig

diff --git a/security/Kconfig b/security/Kconfig
index 5721847a7a62f46715347596fcd7989e476567b8..fb363cd81cf6db10753c69a3726c31143c3823b2 100644 (file)
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -143,6 +143,22 @@ config INTEL_TXT
 
          If you are unsure as to whether this is required, 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