diff options
| author | maximilian attems <max@stro.at> | 2008-04-16 19:36:36 +0200 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2008-04-18 20:26:18 +1000 |
| commit | 5f46ce14bd432cf52bf91079270af164ca48f821 (patch) | |
| tree | ae8129b0ba3743b67ba69af83c7c8aa6950e4f15 /security/Kconfig | |
| parent | 27cc2a6e572e1a86a08a02918517558f175f6974 (diff) | |
| download | lwn-5f46ce14bd432cf52bf91079270af164ca48f821.tar.gz lwn-5f46ce14bd432cf52bf91079270af164ca48f821.zip | |
security: enhance DEFAULT_MMAP_MIN_ADDR description
Got burned by setting the proposed default of 65536
across all Debian archs.
Thus proposing to be more specific on which archs you may
set this. Also propose a value for arm and friends that
doesn't break sshd.
Reword to mention working archs ia64 and ppc64 too.
Signed-off-by: maximilian attems <max@stro.at>
Cc: Martin Michlmayr <tbm@cyrius.com>
Cc: Gordon Farquharson <gordonfarquharson@gmail.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/Kconfig')
| -rw-r--r-- | security/Kconfig | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/security/Kconfig b/security/Kconfig index 5dfc206748cf..49b51f964897 100644 --- a/security/Kconfig +++ b/security/Kconfig @@ -113,10 +113,12 @@ config SECURITY_DEFAULT_MMAP_MIN_ADDR from userspace allocation. Keeping a user from writing to low pages can help reduce the impact of kernel NULL pointer bugs. - For most users with lots of address space a value of 65536 is - reasonable and should cause no problems. Programs which use vm86 - functionality would either need additional permissions from either - the LSM or the capabilities module or have this protection disabled. + 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. This value can be changed after boot using the /proc/sys/vm/mmap_min_addr tunable. |