linux/mm
Mike Kravetz e5bbc8a6c9 mm/hugetlb.c: fix reservation race when freeing surplus pages
return_unused_surplus_pages() decrements the global reservation count,
and frees any unused surplus pages that were backing the reservation.

Commit 7848a4bf51 ("mm/hugetlb.c: add cond_resched_lock() in
return_unused_surplus_pages()") added a call to cond_resched_lock in the
loop freeing the pages.

As a result, the hugetlb_lock could be dropped, and someone else could
use the pages that will be freed in subsequent iterations of the loop.
This could result in inconsistent global hugetlb page state, application
api failures (such as mmap) failures or application crashes.

When dropping the lock in return_unused_surplus_pages, make sure that
the global reservation count (resv_huge_pages) remains sufficiently
large to prevent someone else from claiming pages about to be freed.

Analyzed by Paul Cassella.

Fixes: 7848a4bf51 ("mm/hugetlb.c: add cond_resched_lock() in return_unused_surplus_pages()")
Link: http://lkml.kernel.org/r/1483991767-6879-1-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Paul Cassella <cassella@cray.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: <stable@vger.kernel.org>	[3.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-10 18:31:55 -08:00
..
kasan Power management material for v4.10-rc1 2016-12-13 10:41:53 -08:00
backing-dev.c writeback: track if we're sleeping on progress in balance_dirty_pages() 2016-11-08 08:28:55 -07:00
balloon_compaction.c mm: balloon: use general non-lru movable page feature 2016-07-26 16:19:19 -07:00
bootmem.c mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping 2016-10-11 15:06:33 -07:00
cleancache.c
cma.c mm/cma.c: check the max limit for cma allocation 2016-11-11 08:12:37 -08:00
cma.h
cma_debug.c
compaction.c mm, compaction: allow compaction for GFP_NOFS requests 2016-12-14 16:04:07 -08:00
debug.c mm, debug: print raw struct page data in __dump_page() 2016-12-12 18:55:08 -08:00
debug_page_ref.c
dmapool.c
early_ioremap.c
fadvise.c mm: fadvise: avoid expensive remote LRU cache draining after FADV_DONTNEED 2016-12-20 09:48:46 -08:00
failslab.c
filemap.c dax: fix deadlock with DAX 4k holes 2017-01-10 18:31:54 -08:00
frame_vector.c mm: replace get_vaddr_frames() write/force parameters with gup_flags 2016-10-19 08:11:24 -07:00
frontswap.c mm, frontswap: convert frontswap_enabled to static key 2016-07-26 16:19:19 -07:00
gup.c mm: unexport __get_user_pages_unlocked() 2016-12-14 16:04:09 -08:00
highmem.c
huge_memory.c mm: pmd dirty emulation in page fault handler 2017-01-10 18:31:55 -08:00
hugetlb.c mm/hugetlb.c: fix reservation race when freeing surplus pages 2017-01-10 18:31:55 -08:00
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c mm: Add a user_ns owner to mm_struct and fix ptrace permission checks 2016-11-22 11:49:48 -06:00
internal.h mm: add PageWaiters indicating tasks are waiting for a page bit 2016-12-25 11:54:48 -08:00
interval_tree.c
Kconfig mm: THP page cache support for ppc64 2016-12-12 18:55:08 -08:00
Kconfig.debug PM / Hibernate: allow hibernation with PAGE_POISONING_ZERO 2016-09-13 02:35:27 +02:00
khugepaged.c mm: get rid of __GFP_OTHER_NODE 2017-01-10 18:31:55 -08:00
kmemcheck.c
kmemleak-test.c
kmemleak.c kmemleak: fix reference to Documentation 2016-12-12 18:55:07 -08:00
ksm.c mm,ksm: add __GFP_HIGH to the allocation in alloc_stable_node() 2016-10-07 18:46:29 -07:00
list_lru.c mm/list_lru.c: avoid error-path NULL pointer deref 2016-10-27 18:43:42 -07:00
maccess.c
madvise.c mm: add tlb_remove_check_page_size_change to track page size change 2016-12-12 18:55:07 -08:00
Makefile Disable the __builtin_return_address() warning globally after all 2016-10-12 10:23:41 -07:00
memblock.c mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping 2016-10-11 15:06:33 -07:00
memcontrol.c mm, memcg: fix the active list aging for lowmem requests when memcg is enabled 2017-01-10 18:31:55 -08:00
memory-failure.c mm: Use owner_priv bit for PageSwapCache, valid when PageSwapBacked 2016-12-25 11:54:48 -08:00
memory.c dax: wrprotect pmd_t in dax_mapping_entry_mkclean 2017-01-10 18:31:54 -08:00
memory_hotplug.c mm: remove x86-only restriction of movable_node 2016-12-12 18:55:07 -08:00
mempolicy.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mempool.c Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements" 2016-07-28 16:07:41 -07:00
memtest.c
migrate.c mm: Use owner_priv bit for PageSwapCache, valid when PageSwapBacked 2016-12-25 11:54:48 -08:00
mincore.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mlock.c thp: fix corner case of munlock() of PTE-mapped THPs 2016-11-30 16:32:52 -08:00
mm_init.c
mmap.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mremap.c mremap: move_ptes: check pte dirty after its removal 2016-11-29 08:20:24 -08:00
msync.c
nobootmem.c mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping 2016-10-11 15:06:33 -07:00
nommu.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
oom_kill.c oom: print nodemask in the oom report 2016-10-07 18:46:29 -07:00
page-writeback.c radix-tree: delete radix_tree_range_tag_if_tagged() 2016-12-14 16:04:10 -08:00
page_alloc.c mm: rename __page_frag functions to __page_frag_cache, drop order from drain 2017-01-10 18:31:55 -08:00
page_counter.c
page_ext.c mm/page_ext: support extra space allocation by page_ext user 2016-10-07 18:46:27 -07:00
page_idle.c mm, vmscan: move lru_lock to the node 2016-07-28 16:07:41 -07:00
page_io.c writeback: add wbc_to_write_flags() 2016-11-02 10:24:03 -06:00
page_isolation.c mm/page_isolation: fix typo: "paes" -> "pages" 2016-10-07 18:46:29 -07:00
page_owner.c mm/page_owner: don't define fields on struct page_ext by hard-coding 2016-10-07 18:46:27 -07:00
page_poison.c
pagewalk.c
percpu-km.c
percpu-vm.c
percpu.c Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2016-12-13 12:34:47 -08:00
pgtable-generic.c
process_vm_access.c mm: unexport __get_user_pages_unlocked() 2016-12-14 16:04:09 -08:00
quicklist.c
readahead.c mm: don't cap request size based on read-ahead setting 2016-12-12 18:55:08 -08:00
rmap.c mm, rmap: handle anon_vma_prepare() common case inline 2016-12-12 18:55:08 -08:00
shmem.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
slab.c mm/slab.c: fix SLAB freelist randomization duplicate entries 2017-01-10 18:31:55 -08:00
slab.h mm, slab: maintain total slab count instead of active count 2016-12-12 18:55:07 -08:00
slab_common.c mm/slab_common.c: check kmem_create_cache flags are common 2016-12-12 18:55:06 -08:00
slob.c slub: move synchronize_sched out of slab_mutex on shrink 2016-12-12 18:55:06 -08:00
slub.c slub: avoid false-postive warning 2016-12-12 18:55:06 -08:00
sparse-vmemmap.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
sparse.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
swap.c mm: add PageWaiters indicating tasks are waiting for a page bit 2016-12-25 11:54:48 -08:00
swap_cgroup.c
swap_state.c mm, swap: use offset of swap entry as key of swap cache 2016-10-07 18:46:28 -07:00
swapfile.c mm: support anonymous stable page 2017-01-10 18:31:55 -08:00
truncate.c mm: Invalidate DAX radix tree entries only if appropriate 2016-12-26 20:29:24 -08:00
usercopy.c mm: usercopy: Check for module addresses 2016-09-20 16:07:39 -07:00
userfaultfd.c
util.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
vmacache.c mm: unrig VMA cache hit ratio 2016-10-07 18:46:27 -07:00
vmalloc.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
vmpressure.c
vmscan.c mm, memcg: fix the active list aging for lowmem requests when memcg is enabled 2017-01-10 18:31:55 -08:00
vmstat.c mm/vmstat: Convert to hotplug state machine 2016-12-02 00:52:35 +01:00
workingset.c mm: workingset: fix use-after-free in shadow node shrinker 2017-01-07 18:22:40 -08:00
z3fold.c
zbud.c
zpool.c
zsmalloc.c mm/zsmalloc: Convert to hotplug state machine 2016-12-02 00:52:36 +01:00
zswap.c mm/zswap: Convert pool to hotplug state machine 2016-12-02 00:52:36 +01:00