1
linux/mm
Linus Torvalds 320b2b8de1 mm: keep a guard page below a grow-down stack segment
This is a rather minimally invasive patch to solve the problem of the
user stack growing into a memory mapped area below it.  Whenever we fill
the first page of the stack segment, expand the segment down by one
page.

Now, admittedly some odd application might _want_ the stack to grow down
into the preceding memory mapping, and so we may at some point need to
make this a process tunable (some people might also want to have more
than a single page of guarding), but let's try the minimal approach
first.

Tested with trivial application that maps a single page just below the
stack, and then starts recursing.  Without this, we will get a SIGSEGV
_after_ the stack has smashed the mapping.  With this patch, we'll get a
nice SIGBUS just as the stack touches the page just above the mapping.

Requested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-12 17:54:33 -07:00
..
backing-dev.c writeback: avoid unnecessary calculation of bdi dirty thresholds 2010-08-12 08:43:29 -07:00
bootmem.c
bounce.c
compaction.c
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap_xip.c
filemap.c gcc-4.6: mm: fix unused but set warnings 2010-08-09 20:44:58 -07:00
fremap.c
highmem.c
hugetlb.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2010-08-12 10:15:10 -07:00
hwpoison-inject.c HWPOISON, hugetlb: support hwpoison injection for hugepage 2010-08-11 09:23:11 +02:00
init-mm.c mm: provide init_mm mm_context initializer 2010-08-09 20:44:54 -07:00
internal.h
Kconfig
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c ksm: cleanup for mm_slots_hash 2010-08-09 20:45:03 -07:00
maccess.c
madvise.c
Makefile
memblock.c
memcontrol.c memcg: convert to use zone_to_nid() from bare zone->zone_pgdat->node_id 2010-08-11 08:59:19 -07:00
memory_hotplug.c
memory-failure.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2010-08-12 10:15:10 -07:00
memory.c mm: keep a guard page below a grow-down stack segment 2010-08-12 17:54:33 -07:00
mempolicy.c mempolicy: reduce stack size of migrate_pages() 2010-08-09 20:44:58 -07:00
mempool.c
migrate.c mm: extend KSM refcounts to the anon_vma root 2010-08-09 20:44:55 -07:00
mincore.c
mlock.c
mm_init.c
mmap.c mmap: remove unnecessary lock from __vma_link 2010-08-09 20:44:58 -07:00
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c memcg: use find_lock_task_mm() in memory cgroups oom 2010-08-11 08:59:19 -07:00
page_alloc.c vmscan: kill prev_priority completely 2010-08-09 20:45:00 -07:00
page_cgroup.c
page_io.c
page_isolation.c
page-writeback.c writeback: add comment to the dirty limit functions 2010-08-12 08:43:30 -07:00
pagewalk.c
percpu_up.c
percpu-km.c
percpu-vm.c
percpu.c
prio_tree.c
quicklist.c
readahead.c
rmap.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2010-08-12 10:15:10 -07:00
shmem.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-08-10 11:26:52 -07:00
slab.c gcc-4.6: mm: fix unused but set warnings 2010-08-09 20:44:58 -07:00
slob.c
slub.c
sparse-vmemmap.c
sparse.c
swap_state.c
swap.c
swapfile.c hibernation: freeze swap at hibernation 2010-08-09 20:45:04 -07:00
thrash.c
truncate.c
util.c mm: use memdup_user 2010-08-09 20:44:54 -07:00
vmalloc.c Merge branch 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen 2010-08-12 09:09:41 -07:00
vmscan.c memcg: remove nid and zid argument from mem_cgroup_soft_limit_reclaim() 2010-08-11 08:59:19 -07:00
vmstat.c vmscan: kill prev_priority completely 2010-08-09 20:45:00 -07:00