diff options
| author | David S. Miller <davem@davemloft.net> | 2009-06-15 03:02:23 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-06-15 03:02:23 -0700 |
| commit | 9cbc1cb8cd46ce1f7645b9de249b2ce8460129bb (patch) | |
| tree | 8d104ec2a459346b99413b0b77421ca7b9936c1a /mm/Kconfig | |
| parent | ca44d6e60f9de26281fda203f58b570e1748c015 (diff) | |
| parent | 45e3e1935e2857c54783291107d33323b3ef33c8 (diff) | |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
Documentation/feature-removal-schedule.txt
drivers/scsi/fcoe/fcoe.c
net/core/drop_monitor.c
net/core/net-traces.c
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index c2b57d81e15..71830ba7b98 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -226,6 +226,25 @@ config HAVE_MLOCKED_PAGE_BIT config MMU_NOTIFIER bool +config DEFAULT_MMAP_MIN_ADDR + int "Low address space to protect from user allocation" + default 4096 + 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 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. + + config NOMMU_INITIAL_TRIM_EXCESS int "Turn on mmap() excess space trimming before booting" depends on !MMU |