Tetsuo Handa 7880fc5415 mm,vmscan: Make unregister_shrinker() no-op if register_shrinker() failed. ... commit bb422a738f upstream. Syzbot caught an oops at unregister_shrinker() because combination of commit 1d3d4437ea ("vmscan: per-node deferred work") and fault injection made register_shrinker() fail and the caller of register_shrinker() did not check for failure. ---------- [ 554.881422] FAULT_INJECTION: forcing a failure. [ 554.881422] name failslab, interval 1, probability 0, space 0, times 0 [ 554.881438] CPU: 1 PID: 13231 Comm: syz-executor1 Not tainted 4.14.0-rc8+ #82 [ 554.881443] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 554.881445] Call Trace: [ 554.881459] dump_stack+0x194/0x257 [ 554.881474] ? arch_local_irq_restore+0x53/0x53 [ 554.881486] ? find_held_lock+0x35/0x1d0 [ 554.881507] should_fail+0x8c0/0xa40 [ 554.881522] ? fault_create_debugfs_attr+0x1f0/0x1f0 [ 554.881537] ? check_noncircular+0x20/0x20 [ 554.881546] ? find_next_zero_bit+0x2c/0x40 [ 554.881560] ? ida_get_new_above+0x421/0x9d0 [ 554.881577] ? find_held_lock+0x35/0x1d0 [ 554.881594] ? __lock_is_held+0xb6/0x140 [ 554.881628] ? check_same_owner+0x320/0x320 [ 554.881634] ? lock_downgrade+0x990/0x990 [ 554.881649] ? find_held_lock+0x35/0x1d0 [ 554.881672] should_failslab+0xec/0x120 [ 554.881684] __kmalloc+0x63/0x760 [ 554.881692] ? lock_downgrade+0x990/0x990 [ 554.881712] ? register_shrinker+0x10e/0x2d0 [ 554.881721] ? trace_event_raw_event_module_request+0x320/0x320 [ 554.881737] register_shrinker+0x10e/0x2d0 [ 554.881747] ? prepare_kswapd_sleep+0x1f0/0x1f0 [ 554.881755] ? _down_write_nest_lock+0x120/0x120 [ 554.881765] ? memcpy+0x45/0x50 [ 554.881785] sget_userns+0xbcd/0xe20 (...snipped...) [ 554.898693] kasan: CONFIG_KASAN_INLINE enabled [ 554.898724] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 554.898732] general protection fault: 0000 [#1] SMP KASAN [ 554.898737] Dumping ftrace buffer: [ 554.898741] (ftrace buffer empty) [ 554.898743] Modules linked in: [ 554.898752] CPU: 1 PID: 13231 Comm: syz-executor1 Not tainted 4.14.0-rc8+ #82 [ 554.898755] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 554.898760] task: ffff8801d1dbe5c0 task.stack: ffff8801c9e38000 [ 554.898772] RIP: 0010:__list_del_entry_valid+0x7e/0x150 [ 554.898775] RSP: 0018:ffff8801c9e3f108 EFLAGS: 00010246 [ 554.898780] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 554.898784] RDX: 0000000000000000 RSI: ffff8801c53c6f98 RDI: ffff8801c53c6fa0 [ 554.898788] RBP: ffff8801c9e3f120 R08: 1ffff100393c7d55 R09: 0000000000000004 [ 554.898791] R10: ffff8801c9e3ef70 R11: 0000000000000000 R12: 0000000000000000 [ 554.898795] R13: dffffc0000000000 R14: 1ffff100393c7e45 R15: ffff8801c53c6f98 [ 554.898800] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 554.898804] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 554.898807] CR2: 00000000dbc23000 CR3: 00000001c7269000 CR4: 00000000001406e0 [ 554.898813] DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 [ 554.898816] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 [ 554.898818] Call Trace: [ 554.898828] unregister_shrinker+0x79/0x300 [ 554.898837] ? perf_trace_mm_vmscan_writepage+0x750/0x750 [ 554.898844] ? down_write+0x87/0x120 [ 554.898851] ? deactivate_super+0x139/0x1b0 [ 554.898857] ? down_read+0x150/0x150 [ 554.898864] ? check_same_owner+0x320/0x320 [ 554.898875] deactivate_locked_super+0x64/0xd0 [ 554.898883] deactivate_super+0x141/0x1b0 ---------- Since allowing register_shrinker() callers to call unregister_shrinker() when register_shrinker() failed can simplify error recovery path, this patch makes unregister_shrinker() no-op when register_shrinker() failed. Also, reset shrinker->nr_deferred in case unregister_shrinker() was by error called twice. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Aliaksei Karaliou <akaraliou.dev@gmail.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Glauber Costa <glauber@scylladb.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-02-25 11:07:46 +01:00
..
kasan	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
backing-dev.c	mm/backing-dev.c: fix an error handling path in 'cgwb_create()'	2017-09-11 14:16:44 -06:00
balloon_compaction.c	mm/migrate: new migrate mode MIGRATE_SYNC_NO_COPY	2017-09-08 18:26:46 -07:00
bootmem.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
cleancache.c	fs: switch ->s_uuid to uuid_t	2017-06-05 16:59:12 +02:00
cma.c	mm/cma.c: take __GFP_NOWARN into account in cma_alloc()	2017-10-13 16:18:32 -07:00
cma.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
cma_debug.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
compaction.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
debug.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
debug_page_ref.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
dmapool.c
early_ioremap.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fadvise.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
failslab.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
filemap.c	mm: have filemap_check_and_advance_wb_err clear AS_EIO/AS_ENOSPC	2017-10-03 17:54:24 -07:00
frame_vector.c	mm: fail get_vaddr_frames() for filesystem-dax mappings	2017-12-05 11:26:28 +01:00
frontswap.c
gup.c	mm, x86/mm: Fix performance regression in get_user_pages_fast()	2017-12-10 13:40:43 +01:00
highmem.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
hmm.c	mm/hmm: avoid bloating arch that do not make use of HMM	2017-09-08 18:26:46 -07:00
huge_memory.c	mm, thp: Do not make page table dirty unconditionally in touch_p[mu]d()	2017-12-05 11:26:28 +01:00
hugetlb.c	mm/hugetlb: fix NULL-pointer dereference on 5-level paging machine	2017-12-05 11:26:30 +01:00
hugetlb_cgroup.c
hwpoison-inject.c	mm: hwpoison: call shake_page() unconditionally	2017-05-03 15:52:12 -07:00
init-mm.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
internal.h	mm, oom: do not rely on TIF_MEMDIE for memory reserves access	2017-09-06 17:27:30 -07:00
interval_tree.c	lib/interval_tree: fast overlap detection	2017-09-08 18:26:49 -07:00
Kconfig	mm/hmm: avoid bloating arch that do not make use of HMM	2017-09-08 18:26:46 -07:00
Kconfig.debug	kmemcheck: rip it out	2018-02-22 15:42:24 +01:00
khugepaged.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
kmemleak-test.c
kmemleak.c	kmemcheck: remove annotations	2018-02-22 15:42:23 +01:00
ksm.c	ksm: fix unlocked iteration over vmas in cmp_and_merge_page()	2017-10-03 17:54:23 -07:00
list_lru.c	mm: memcontrol: use vmalloc fallback for large kmem memcg arrays	2017-10-03 17:54:25 -07:00
maccess.c
madvise.c	mm/madvise.c: fix madvise() infinite loop under special circumstances	2017-12-05 11:26:29 +01:00
Makefile	kmemcheck: rip it out	2018-02-22 15:42:24 +01:00
memblock.c	mm/memblock.c: reversed logic in memblock_discard()	2017-08-25 16:12:46 -07:00
memcontrol.c	Revert "defer call to mem_cgroup_sk_alloc()"	2018-02-13 10:19:48 +01:00
memory-failure.c	x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pages	2018-02-22 15:42:31 +01:00
memory.c	mm: hide a #warning for COMPILE_TEST	2018-02-22 15:42:27 +01:00
memory_hotplug.c	mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long	2017-10-03 17:54:26 -07:00
mempolicy.c	mm/mempolicy: fix NUMA_INTERLEAVE_HIT counter	2017-10-13 16:18:32 -07:00
mempool.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
memtest.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
migrate.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mincore.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mlock.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mm_init.c
mmap.c	mm, oom_reaper: fix memory corruption	2017-12-20 10:10:18 +01:00
mmu_context.c
mmu_notifier.c	mm/mmu_notifier: kill invalidate_page	2017-08-31 16:13:00 -07:00
mmzone.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mprotect.c	mm/mprotect: add a cond_resched() inside change_pmd_range()	2018-01-10 09:31:17 +01:00
mremap.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
msync.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
nobootmem.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
nommu.c	Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-09-14 18:13:32 -07:00
oom_kill.c	mm, oom_reaper: fix memory corruption	2017-12-20 10:10:18 +01:00
page-writeback.c	mm: rename global_page_state to global_zone_page_state	2017-09-06 17:27:29 -07:00
page_alloc.c	kmemcheck: remove annotations	2018-02-22 15:42:23 +01:00
page_counter.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_ext.c	mm/page_ext.c: check if page_ext is not prepared	2017-11-24 08:37:05 +01:00
page_idle.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_io.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_isolation.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_owner.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_poison.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
page_vma_mapped.c	mm, page_vma_mapped: Drop faulty pointer arithmetics in check_pte()	2018-01-23 19:58:21 +01:00
pagewalk.c	mm/pagewalk.c: report holes in hugetlb ranges	2017-11-24 08:37:04 +01:00
percpu-internal.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
percpu-km.c	percpu: replace area map allocator with bitmap	2017-07-26 17:41:05 -04:00
percpu-stats.c	percpu: fix starting offset for chunk statistics traversal	2017-09-27 14:45:57 -07:00
percpu-vm.c	percpu: fix static checker warnings in pcpu_destroy_chunk	2017-06-29 11:23:38 -04:00
percpu.c	mm, percpu: add support for __GFP_NOWARN flag	2017-10-19 13:13:49 +01:00
pgtable-generic.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
process_vm_access.c
quicklist.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
readahead.c
rmap.c	lib/interval_tree: fast overlap detection	2017-09-08 18:26:49 -07:00
rodata_test.c	mm: fix RODATA_TEST failure "rodata_test: test data was not read only"	2017-10-03 17:54:24 -07:00
shmem.c	mm: treewide: remove GFP_TEMPORARY allocation flag	2017-09-13 18:53:16 -07:00
slab.c	kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK	2018-02-22 15:42:23 +01:00
slab.h	kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK	2018-02-22 15:42:23 +01:00
slab_common.c	kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK	2018-02-22 15:42:23 +01:00
slob.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
slub.c	kmemcheck: rip it out	2018-02-22 15:42:24 +01:00
sparse-vmemmap.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
sparse.c	mm/sparse.c: wrong allocation for mem_section	2018-01-10 09:31:17 +01:00
swap.c	mm: avoid marking swap cached page as lazyfree	2017-10-03 17:54:24 -07:00
swap_cgroup.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
swap_slots.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
swap_state.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
swapfile.c	mm, swap: fix race between swap count continuation operations	2017-11-03 07:39:19 -07:00
truncate.c	mm/truncate.c: fix THP handling in invalidate_mapping_pages()	2017-07-10 16:32:32 -07:00
usercopy.c	mm/usercopy: Drop extra is_vmalloc_or_module() check	2017-04-05 12:30:18 -07:00
userfaultfd.c	userfaultfd: shmem: wire up shmem_mfill_zeropage_pte	2017-09-06 17:27:28 -07:00
util.c	mm: rename global_page_state to global_zone_page_state	2017-09-06 17:27:29 -07:00
vmacache.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
vmalloc.c	Revert "vmalloc: back off when the current task is killed"	2017-10-13 16:18:32 -07:00
vmpressure.c	mm, vmpressure: pass-through notification support	2017-07-10 16:32:31 -07:00
vmscan.c	mm,vmscan: Make unregister_shrinker() no-op if register_shrinker() failed.	2018-02-25 11:07:46 +01:00
vmstat.c	mm: consider the number in local CPUs when reading NUMA stats	2017-09-08 18:26:47 -07:00
workingset.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
z3fold.c	mm/z3fold.c: use kref to prevent page free/compact race	2017-11-30 08:40:44 +00:00
zbud.c
zpool.c
zsmalloc.c	zsmalloc: calling zs_map_object() from irq is a bug	2017-12-14 09:53:10 +01:00
zswap.c	mm/zswap.c: delete an error message for a failed memory allocation in zswap_dstmem_prepare()	2017-07-06 16:24:35 -07:00