linux/mm
Frantisek Hrbata ff05b6f7ae oom: fix integer overflow of points in oom_badness
An integer overflow will happen on 64bit archs if task's sum of rss,
swapents and nr_ptes exceeds (2^31)/1000 value.  This was introduced by
commit

f755a04 oom: use pte pages in OOM score

where the oom score computation was divided into several steps and it's no
longer computed as one expression in unsigned long(rss, swapents, nr_pte
are unsigned long), where the result value assigned to points(int) is in
range(1..1000).  So there could be an int overflow while computing

176          points *= 1000;

and points may have negative value. Meaning the oom score for a mem hog task
will be one.

196          if (points <= 0)
197                  return 1;

For example:
[ 3366]     0  3366 35390480 24303939   5       0             0 oom01
Out of memory: Kill process 3366 (oom01) score 1 or sacrifice child

Here the oom1 process consumes more than 24303939(rss)*4096~=92GB physical
memory, but it's oom score is one.

In this situation the mem hog task is skipped and oom killer kills another and
most probably innocent task with oom score greater than one.

The points variable should be of type long instead of int to prevent the
int overflow.

Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>		[2.6.36+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-20 10:25:04 -08:00
..
backing-dev.c backing-dev: ensure wakeup_timer is deleted 2011-11-11 13:29:04 +01:00
bootmem.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
bounce.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
cleancache.c mm: cleancache core ops functions and config 2011-05-26 10:01:36 -06:00
compaction.c mm: compaction: make compact_zone_order() static 2011-10-31 17:30:49 -07:00
debug-pagealloc.c debug-pagealloc: add support for highmem pages 2011-10-31 17:30:48 -07:00
dmapool.c mm: fix implicit stat.h usage in dmapool.c 2011-10-31 09:20:12 -04:00
fadvise.c readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM 2010-03-06 11:26:25 -08:00
failslab.c fault-injection: add ability to export fault_attr in arbitrary directory 2011-08-03 14:25:20 -10:00
filemap_xip.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
filemap.c fs: Make write(2) interruptible by a fatal signal 2011-12-02 09:17:05 +08:00
fremap.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
highmem.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
huge_memory.c thp: reduce khugepaged freezing latency 2011-12-09 07:50:28 -08:00
hugetlb.c thp: set compound tail page _count to zero 2011-12-09 07:50:28 -08:00
hwpoison-inject.c Fix common misspellings 2011-03-31 11:26:23 -03:00
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm: thp: tail page refcounting fix 2011-11-02 16:06:57 -07:00
Kconfig memblock: add NO_BOOTMEM config symbol 2011-10-31 17:30:47 -07:00
Kconfig.debug mm: debug-pagealloc: fix kconfig dependency warning 2011-03-22 17:44:02 -07:00
kmemcheck.c kmemcheck: Fix build errors due to missing slab.h 2010-03-30 22:02:32 +09:00
kmemleak-test.c kmemleak: remove memset by using kzalloc 2011-01-27 18:31:51 +00:00
kmemleak.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
ksm.c oom: fix race while temporarily setting current's oom_score_adj 2011-10-31 17:30:45 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c fs: kill i_alloc_sem 2011-07-20 20:47:46 -04:00
Makefile Cross Memory Attach 2011-10-31 17:30:44 -07:00
memblock.c mm/memblock.c: quiet sparse noise 2011-10-31 17:30:50 -07:00
memcontrol.c memcg: keep root group unchanged if creation fails 2011-12-20 10:25:04 -08:00
memory_hotplug.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
memory-failure.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
memory.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mempolicy.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mempool.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
migrate.c mm/migrate.c: pair unlock_page() and lock_page() when migrating huge pages 2011-12-09 07:50:28 -08:00
mincore.c mm: clarify the radix_tree exceptional cases 2011-08-03 14:25:24 -10:00
mlock.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mm_init.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
mmu_context.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmu_notifier.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
mmzone.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
mprotect.c thp: mprotect: transparent huge page support 2011-01-13 17:32:44 -08:00
mremap.c thp: mremap support and TLB optimization 2011-10-31 17:30:48 -07:00
msync.c sanitize vfs_fsync calling conventions 2010-05-21 18:31:21 -04:00
nobootmem.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
nommu.c xen: map foreign pages for shared rings by updating the PTEs directly 2011-11-16 12:13:08 -05:00
oom_kill.c oom: fix integer overflow of points in oom_badness 2011-12-20 10:25:04 -08:00
page_alloc.c mm: Ensure that pfn_valid() is called once per pageblock when reserving pageblocks 2011-12-09 07:50:28 -08:00
page_cgroup.c mm/page_cgroup.c: quiet sparse noise 2011-11-02 16:07:00 -07:00
page_io.c block: kill off REQ_UNPLUG 2011-03-10 08:52:27 +01:00
page_isolation.c mm: page_isolation: codeclean fix comment and rm unneeded val init 2010-10-26 16:52:11 -07:00
page-writeback.c writeback: set max_pause to lowest value on zero bdi_dirty 2011-12-08 10:49:29 +08:00
pagewalk.c pagewalk: fix code comment for THP 2011-07-25 20:57:09 -07:00
percpu-km.c percpu: clear memory allocated with the km allocator 2010-10-02 10:28:42 +03:00
percpu-vm.c percpu: fix chunk range calculation 2011-11-22 08:09:46 -08:00
percpu.c percpu: fix per_cpu_ptr_to_phys() handling of non-page-aligned addresses 2011-12-15 11:41:40 -08:00
pgtable-generic.c mm/pgtable-generic.c: fix CONFIG_SWAP=n build 2011-01-26 10:49:58 +10:00
prio_tree.c sanitize <linux/prefetch.h> usage 2011-05-20 12:50:29 -07:00
process_vm_access.c Cross Memory Attach 2011-10-31 17:30:44 -07:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
rmap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
shmem.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
slab.c slab, lockdep: Fix silly bug 2011-12-05 09:44:00 +01:00
slob.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
slub.c slub: avoid potential NULL dereference or corruption 2011-11-24 08:44:19 +02:00
sparse-vmemmap.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
sparse.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
swap_state.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
swap.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
swapfile.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
thrash.c mm/thrash.c: quiet sparse noise 2011-10-31 17:30:50 -07:00
truncate.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
util.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
vmalloc.c mm: vmalloc: check for page allocation failure before vmlist insertion 2011-12-09 07:50:29 -08:00
vmscan.c vmscan: use atomic-long for shrinker batching 2011-12-09 07:50:27 -08:00
vmstat.c mm/vmstat.c: cache align vm_stat 2011-10-31 17:30:51 -07:00