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| author | Eric Paris <eparis@redhat.com> | 2009-07-31 12:54:11 -0400 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2009-08-17 15:09:11 +1000 |
| commit | 788084aba2ab7348257597496befcbccabdc98a3 (patch) | |
| tree | 2da42d746d67b16ef705229a1b5a3528ec19c725 /security/Kconfig | |
| parent | 8cf948e744e0218af604c32edecde10006dc8e9e (diff) | |
| download | linux-788084aba2ab7348257597496befcbccabdc98a3.tar.gz linux-788084aba2ab7348257597496befcbccabdc98a3.tar.bz2 linux-788084aba2ab7348257597496befcbccabdc98a3.zip | |
Security/SELinux: seperate lsm specific mmap_min_addr
Currently SELinux enforcement of controls on the ability to map low memory
is determined by the mmap_min_addr tunable. This patch causes SELinux to
ignore the tunable and instead use a seperate Kconfig option specific to how
much space the LSM should protect.
The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
permissions will always protect the amount of low memory designated by
CONFIG_LSM_MMAP_MIN_ADDR.
This allows users who need to disable the mmap_min_addr controls (usual reason
being they run WINE as a non-root user) to do so and still have SELinux
controls preventing confined domains (like a web server) from being able to
map some area of low memory.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/Kconfig')
| -rw-r--r-- | security/Kconfig | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/security/Kconfig b/security/Kconfig index d23c839038f0..9c60c346a91d 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 from user allocation" + depends on SECURITY && SECURITY_SELINUX + default 65535 + 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 |