[PATCH] Kconfig: enhance DEFAULT_MMAP_MIN_ADDR description

From: maximilian attems
Date: Wed Apr 16 2008 - 13:14:09 EST


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.

Signed-off-by: maximilian attems <max@xxxxxxx>
Cc: Martin Michlmayr <tbm@xxxxxxxxxx>
Cc: Gordon Farquharson <gordonfarquharson@xxxxxxxxx>
---
security/Kconfig | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/security/Kconfig b/security/Kconfig
index 5dfc206..cc1e4bd 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -113,8 +113,9 @@ 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
+ For most 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.

--
1.5.5

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