Krzysztof Kozlowski 5b808a2300 swap: fix set_blocksize race during swapon/swapoff ...

Fix race between swapoff and swapon.  Swapoff used old_block_size from
swap_info outside of swapon_mutex so it could be overwritten by
concurrent swapon.

The race has visible effect only if more than one swap block device
exists with different block sizes (e.g.  /dev/sda1 with block size 4096
and /dev/sdb1 with 512).  In such case it leads to setting the blocksize
of swapped off device with wrong blocksize.

The bug can be triggered with multiple concurrent swapoff and swapon:
0. Swap for some device is on.
1. swapoff:
First the swapoff is called on this device and "struct swap_info_struct
*p" is assigned. This is done under swap_lock however this lock is
released for the call try_to_unuse().

2. swapon:
After the assignment above (and before acquiring swapon_mutex &
swap_lock by swapoff) the swapon is called on the same device.
The p->old_block_size is assigned to the value of block_size the device.
This block size should be the same as previous but sometimes it is not.
The swapon ends successfully.

3. swapoff:
Swapoff resumes, grabs the locks and mutex and continues to disable this
swap device. Now it sets the block size to value taken from swap_info
which was overwritten by swapon in 2.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: Weijie Yang <weijie.yang.kh@gmail.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: Minchan Kim <minchan@kernel.org>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2013-10-16 21:35:53 -07:00

..

backing-dev.c

mm/backing-dev.c: check user buffer length before copying data to the related user buffer

2013-09-11 15:58:03 -07:00

balloon_compaction.c

mm: introduce a common interface for balloon pages mobility

2012-12-11 17:22:26 -08:00

bootmem.c

mm: kill free_all_bootmem_node()

2013-07-03 16:07:39 -07:00

bounce.c

mm/bounce.c: fix a regression where MS_SNAP_STABLE (stable pages snapshotting) was ignored

2013-09-30 14:31:02 -07:00

cleancache.c

mm: cleancache: clean up cleancache_enabled

2013-04-30 17:04:01 -07:00

compaction.c

mm/compaction.c: periodically schedule when freeing pages

2013-09-30 14:31:01 -07:00

debug-pagealloc.c

…

dmapool.c

dmapool: make DMAPOOL_DEBUG detect corruption of free marker

2012-12-11 17:22:24 -08:00

fadvise.c

teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long

2013-03-03 22:46:22 -05:00

failslab.c

…

filemap_xip.c

lift sb_start_write() out of ->write()

2013-04-09 14:12:56 -04:00

filemap.c

mm: memcg: handle non-error OOM situations more gracefully

2013-10-16 21:35:53 -07:00

fremap.c

mm: save soft-dirty bits on file pages

2013-08-13 17:57:48 -07:00

frontswap.c

frontswap: fix incorrect zeroing and allocation size for frontswap_map

2013-06-12 16:29:46 -07:00

highmem.c

Some nice cleanups, and even a patch my wife did as a "live" demo for

2012-12-20 08:37:05 -08:00

huge_memory.c

Merge branch 'akpm' (patches from Andrew Morton)

2013-09-12 15:44:27 -07:00

hugetlb_cgroup.c

cgroup: pass around cgroup_subsys_state instead of cgroup in file methods

2013-08-08 20:11:24 -04:00

hugetlb.c

mm: hugetlb: initialize PG_reserved for tail pages of gigantic compound pages

2013-10-16 21:35:52 -07:00

hwpoison-inject.c

mm/hwpoison: fix the lack of one reference count against poisoned page

2013-09-30 14:31:03 -07:00

init-mm.c

…

internal.h

mm: vmscan: fix do_try_to_free_pages() livelock

2013-09-11 15:58:01 -07:00

interval_tree.c

mm: add CONFIG_DEBUG_VM_RB build option

2012-10-09 16:22:42 +09:00

Kconfig

powerpc: Fix memory hotplug with sparse vmemmap

2013-10-03 17:21:38 +10:00

Kconfig.debug

…

kmemcheck.c

…

kmemleak-test.c

…

kmemleak.c

mm: replace strict_strtoul() with kstrtoul()

2013-09-11 15:57:11 -07:00

ksm.c

mm: replace strict_strtoul() with kstrtoul()

2013-09-11 15:57:11 -07:00

list_lru.c

list_lru: dynamically adjust node arrays

2013-09-10 18:56:32 -04:00

maccess.c

…

madvise.c

mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood

2013-09-30 14:31:02 -07:00

Makefile

list: add a new LRU list type

2013-09-10 18:56:30 -04:00

memblock.c

memblock, numa: binary search node id

2013-09-11 15:57:51 -07:00

memcontrol.c

fs: buffer: move allocation failure loop into the allocator

2013-10-16 21:35:53 -07:00

memory_hotplug.c

ACPI and power management fixes for 3.12-rc1

2013-09-12 11:22:45 -07:00

memory-failure.c

mm/hwpoison: fix false report on 2nd attempt at page recovery

2013-09-30 14:31:02 -07:00

memory.c

mm: memcg: handle non-error OOM situations more gracefully

2013-10-16 21:35:53 -07:00

mempolicy.c

mbind: add BUG_ON(!vma) in new_vma_page()

2013-09-11 15:57:50 -07:00

mempool.c

mm/mempool.c: convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)

2013-09-11 15:58:14 -07:00

migrate.c

mm: migration: do not lose soft dirty bit if page is in migration state

2013-10-16 21:35:52 -07:00

mincore.c

swap: make each swap partition have one address_space

2013-02-23 17:50:17 -08:00

mlock.c

mm/mlock.c: prevent walking off the end of a pagetable in no-pmd configuration

2013-09-30 14:31:02 -07:00

mm_init.c

mm: tune vm_committed_as percpu_counter batching size

2013-07-03 16:07:32 -07:00

mmap.c

mm/mmap: remove unnecessary assignment

2013-09-11 15:58:13 -07:00

mmu_context.c

mm: remove old aio use_mm() comment

2013-05-07 18:38:27 -07:00

mmu_notifier.c

treewide: relase -> release

2013-06-28 14:34:33 +02:00

mmzone.c

mm: rename page struct field helpers

2013-02-23 17:50:18 -08:00

mprotect.c

mm: migration: do not lose soft dirty bit if page is in migration state

2013-10-16 21:35:52 -07:00

mremap.c

mm/mremap.c: call pud_free() after fail calling pmd_alloc()

2013-09-11 15:58:03 -07:00

msync.c

…

nobootmem.c

mm: concentrate modification of totalram_pages into the mm core

2013-07-03 16:07:33 -07:00

nommu.c

mm: remove free_area_cache

2013-07-10 18:11:34 -07:00

oom_kill.c

mm: memcg: handle non-error OOM situations more gracefully

2013-10-16 21:35:53 -07:00

page_alloc.c

revert "mm/memory-hotplug: fix lowmem count overflow when offline pages"

2013-09-30 14:31:01 -07:00

page_cgroup.c

memcontrol: use N_MEMORY instead N_HIGH_MEMORY

2012-12-12 17:38:32 -08:00

page_io.c

aio: Kill aio_rw_vect_retry()

2013-07-30 11:53:12 -04:00

page_isolation.c

mm: memory-hotplug: enable memory hotplug to handle hugepage

2013-09-11 15:57:48 -07:00

page-writeback.c

writeback: fix negative bdi max pause

2013-10-16 21:35:53 -07:00

pagewalk.c

mm/pagewalk.c: walk_page_range should avoid VM_PFNMAP areas

2013-05-24 16:22:53 -07:00

percpu-km.c

…

percpu-vm.c

mm: fix kernel-doc warnings

2012-06-20 14:39:36 -07:00

percpu.c

mm, percpu: Make sure percpu_alloc early parameter has an argument

2012-12-02 06:23:04 -08:00

pgtable-generic.c

mm: move pgtable related functions to right place

2013-09-11 15:57:30 -07:00

process_vm_access.c

Fix: compat_rw_copy_check_uvector() misuse in aio, readv, writev, and security keys

2013-03-12 11:05:45 -07:00

quicklist.c

…

readahead.c

readahead: make context readahead more conservative

2013-09-11 15:57:39 -07:00

rmap.c

thp: account anon transparent huge pages into NR_ANON_PAGES

2013-09-12 15:38:03 -07:00

shmem.c

initmpfs: make rootfs use tmpfs when CONFIG_TMPFS enabled

2013-09-11 15:59:37 -07:00

slab_common.c

slab_common: Do not check for duplicate slab names

2013-09-28 09:47:41 +03:00

slab.c

kernel: delete __cpuinit usage from all core kernel files

2013-07-14 19:36:59 -04:00

slab.h

memcg: check that kmem_cache has memcg_params before accessing it

2013-08-28 19:26:38 -07:00

slob.c

mm/sl[aou]b: Move kmallocXXX functions to common code

2013-09-04 20:51:33 +03:00

slub.c

Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux

2013-09-15 07:15:06 -04:00

sparse-vmemmap.c

sparse-vmemmap: specify vmemmap population range in bytes

2013-04-29 15:54:35 -07:00

sparse.c

mm/sparse: introduce alloc_usemap_and_memmap

2013-09-11 15:58:01 -07:00

swap_state.c

lib/radix-tree.c: make radix_tree_node_alloc() work correctly within interrupt

2013-09-11 15:59:36 -07:00

swap.c

mm: make lru_add_drain_all() selective

2013-09-12 15:38:02 -07:00

swapfile.c

swap: fix set_blocksize race during swapon/swapoff

2013-10-16 21:35:53 -07:00

truncate.c

truncate: drop 'oldsize' truncate_pagecache() parameter

2013-09-12 15:38:02 -07:00

util.c

swap: clean-up #ifdef in page_mapping()

2013-09-11 15:57:31 -07:00

vmalloc.c

mm/vmalloc: use wrapper function get_vm_area_size to caculate size of vm area

2013-09-11 15:58:02 -07:00

vmpressure.c

Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2013-09-03 18:25:03 -07:00

vmscan.c

mm/vmscan.c: don't forget to free shrinker->nr_deferred

2013-10-16 21:35:52 -07:00

vmstat.c

mm: vmscan: fix do_try_to_free_pages() livelock

2013-09-11 15:58:01 -07:00

zbud.c

mm/zbud: fix some trivial typos in comments

2013-09-11 15:57:35 -07:00

zswap.c

mm/zswap: bugfix: memory leak when re-swapon

2013-10-16 21:35:52 -07:00