linux/include
Mel Gorman b22d127a39 mempolicy: fix a race in shared_policy_replace()
shared_policy_replace() use of sp_alloc() is unsafe.  1) sp_node cannot
be dereferenced if sp->lock is not held and 2) another thread can modify
sp_node between spin_unlock for allocating a new sp node and next
spin_lock.  The bug was introduced before 2.6.12-rc2.

Kosaki's original patch for this problem was to allocate an sp node and
policy within shared_policy_replace and initialise it when the lock is
reacquired.  I was not keen on this approach because it partially
duplicates sp_alloc().  As the paths were sp->lock is taken are not that
performance critical this patch converts sp->lock to sp->mutex so it can
sleep when calling sp_alloc().

[kosaki.motohiro@jp.fujitsu.com: Original patch]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:22 +09:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-10-08 07:14:06 +09:00
asm-generic mm, x86, pat: rework linear pfn-mmap tracking 2012-10-09 16:22:16 +09:00
clocksource arm64: Generic timers support 2012-09-17 13:42:20 +01:00
crypto
drm Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2012-10-07 21:13:54 +10:00
keys
linux mempolicy: fix a race in shared_policy_replace() 2012-10-09 16:22:22 +09:00
math-emu
media Merge branch 'exynos-drm-next' of git://git.infradead.org/users/kmpark/linux-samsung into drm-next 2012-10-07 21:06:33 +10:00
memory
misc
mtd
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-10-06 03:11:59 +09:00
pcmcia
ras
rdma IB/core: Add ib_find_exact_cached_pkey() 2012-09-30 20:33:30 -07:00
rxrpc
scsi Prepared for main script 2012-10-03 13:45:43 -07:00
sound Sound updates for 3.7-rc1 2012-10-09 07:07:14 +09:00
target
trace mm: remove __GFP_NO_KSWAPD 2012-10-09 16:22:15 +09:00
uapi UAPI: (Scripted) Disintegrate include/drm 2012-10-04 18:21:50 +01:00
video ARM: clps711x: Remove board support for CEIVA 2012-09-28 21:14:08 +02:00
xen Features: 2012-10-07 07:13:01 +09:00
Kbuild