diff options
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 /mm | |
parent | 8cf948e744e0218af604c32edecde10006dc8e9e (diff) | |
download | linux-stable-788084aba2ab7348257597496befcbccabdc98a3.tar.gz linux-stable-788084aba2ab7348257597496befcbccabdc98a3.tar.bz2 linux-stable-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 'mm')
-rw-r--r-- | mm/Kconfig | 6 | ||||
-rw-r--r-- | mm/mmap.c | 3 | ||||
-rw-r--r-- | mm/nommu.c | 3 |
3 files changed, 3 insertions, 9 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index c948d4ca8bde..fe5f674d7a7d 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -225,9 +225,9 @@ config DEFAULT_MMAP_MIN_ADDR 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 would either need additional - permissions from either the LSM or the capabilities module or have - this protection disabled. + Programs which use vm86 functionality or have some need to map + this low address space will need CAP_SYS_RAWIO or disable this + protection by setting the value to 0. This value can be changed after boot using the /proc/sys/vm/mmap_min_addr tunable. diff --git a/mm/mmap.c b/mm/mmap.c index 34579b23ebd5..8101de490c73 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -88,9 +88,6 @@ int sysctl_overcommit_ratio = 50; /* default is 50% */ int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT; struct percpu_counter vm_committed_as; -/* amount of vm to protect from userspace access */ -unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; - /* * Check that a process has enough memory to allocate a new virtual * mapping. 0 means there is enough memory for the allocation to diff --git a/mm/nommu.c b/mm/nommu.c index 53cab10fece4..28754c40be98 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -69,9 +69,6 @@ int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT; int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS; int heap_stack_gap = 0; -/* amount of vm to protect from userspace access */ -unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; - atomic_long_t mmap_pages_allocated; EXPORT_SYMBOL(mem_map); |