David Rientjes c11600e4fe mm, mempolicy: task->mempolicy must be NULL before dropping final reference ... KASAN allocates memory from the page allocator as part of kmem_cache_free(), and that can reference current->mempolicy through any number of allocation functions. It needs to be NULL'd out before the final reference is dropped to prevent a use-after-free bug: BUG: KASAN: use-after-free in alloc_pages_current+0x363/0x370 at addr ffff88010b48102c CPU: 0 PID: 15425 Comm: trinity-c2 Not tainted 4.8.0-rc2+ #140 ... Call Trace: dump_stack kasan_object_err kasan_report_error __asan_report_load2_noabort alloc_pages_current <-- use after free depot_save_stack save_stack kasan_slab_free kmem_cache_free __mpol_put <-- free do_exit This patch sets current->mempolicy to NULL before dropping the final reference. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1608301442180.63329@chino.kir.corp.google.com Fixes: cd11016e5f ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB") Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> [4.6+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2016-09-01 17:52:01 -07:00
..
kasan	kasan: remove the unnecessary WARN_ONCE from quarantine.c	2016-08-11 16:58:14 -07:00
backing-dev.c	block: fix bdi vs gendisk lifetime mismatch	2016-08-04 14:19:16 -06:00
balloon_compaction.c	mm: balloon: use general non-lru movable page feature	2016-07-26 16:19:19 -07:00
bootmem.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
cleancache.c	cleancache: constify cleancache_ops structure	2016-01-27 09:09:57 -05:00
cma_debug.c
cma.c	mm/cma: silence warnings due to max() usage	2016-05-27 14:49:37 -07:00
cma.h
compaction.c	mm, compaction: simplify contended compaction handling	2016-07-28 16:07:41 -07:00
debug_page_ref.c	mm/page_ref: add tracepoint to track down page reference manipulation	2016-03-17 15:09:34 -07:00
debug.c	mm: introduce page reference manipulation functions	2016-03-17 15:09:34 -07:00
dmapool.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
early_ioremap.c
fadvise.c	mm/fadvise.c: do not discard partial pages with POSIX_FADV_DONTNEED	2016-06-09 14:23:11 -07:00
failslab.c	mm: fault-inject take over bootstrap kmem_cache check	2016-03-15 16:55:16 -07:00
filemap.c	block/mm: make bdev_ops->rw_page() take a bool for read/write	2016-08-07 14:41:02 -06:00
frame_vector.c	mm/gup: Switch all callers of get_user_pages() to not pass tsk/mm	2016-02-16 10:11:12 +01:00
frontswap.c	mm, frontswap: convert frontswap_enabled to static key	2016-07-26 16:19:19 -07:00
gup.c	- ARM: GICv3 ITS emulation and various fixes. Removal of the old	2016-08-02 16:11:27 -04:00
highmem.c	mm/highmem: make nr_free_highpages() handles all highmem zones by itself	2016-05-19 19:12:14 -07:00
huge_memory.c	soft_dirty: fix soft_dirty during THP split	2016-08-26 17:39:35 -07:00
hugetlb_cgroup.c	mm, hugetlb_cgroup: round limit_in_bytes down to hugepage size	2016-05-20 17:58:30 -07:00
hugetlb.c	mm/hugetlb: fix incorrect hugepages count during mem hotplug	2016-08-11 16:58:13 -07:00
hwpoison-inject.c
init-mm.c
internal.h	mm, compaction: simplify contended compaction handling	2016-07-28 16:07:41 -07:00
interval_tree.c
Kconfig	mm: clarify COMPACTION Kconfig text	2016-08-26 17:39:35 -07:00
Kconfig.debug	mm/page_ref: add tracepoint to track down page reference manipulation	2016-03-17 15:09:34 -07:00
khugepaged.c	mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations	2016-07-28 16:07:41 -07:00
kmemcheck.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
kmemleak-test.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
kmemleak.c	kmemleak: don't hang if user disables scanning early	2016-07-28 16:07:41 -07:00
ksm.c	mm: do not pass mm_struct into handle_mm_fault	2016-07-26 16:19:19 -07:00
list_lru.c	mm: memcontrol: move kmem accounting code to CONFIG_MEMCG	2016-01-20 17:09:18 -08:00
maccess.c	x86: remove more uaccess_32.h complexity	2016-05-22 17:21:27 -07:00
madvise.c	mm: make mmap_sem for write waits killable for mm syscalls	2016-05-23 17:04:14 -07:00
Makefile	Implements HARDENED_USERCOPY verification of copy_to_user/copy_from_user	2016-08-08 14:48:14 -07:00
memblock.c	mm/memblock.c: fix NULL dereference error	2016-08-04 20:02:09 -04:00
memcontrol.c	mm: memcontrol: avoid unused function warning	2016-08-26 17:39:35 -07:00
memory_hotplug.c	mm/memory_hotplug.c: initialize per_cpu_nodestats for hotadded pgdats	2016-08-11 16:58:14 -07:00
memory-failure.c	mm: hwpoison: remove incorrect comments	2016-07-28 16:07:41 -07:00
memory.c	mm: move swap-in anonymous page into active list	2016-08-02 17:31:41 -04:00
mempolicy.c	mm, mempolicy: task->mempolicy must be NULL before dropping final reference	2016-09-01 17:52:01 -07:00
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, thp: remove __GFP_NORETRY from khugepaged and madvised allocations	2016-07-28 16:07:41 -07:00
mincore.c	mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage	2016-04-04 10:41:08 -07:00
mlock.c	mm, vmscan: move LRU lists to node	2016-07-28 16:07:41 -07:00
mm_init.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
mmap.c	mm: refuse wrapped vm_brk requests	2016-08-02 19:35:15 -04:00
mmu_context.c	mm/mmu_context, sched/core: Fix mmu_context.h assumption	2016-04-28 11:44:19 +02:00
mmu_notifier.c	fix Christoph's email addresses	2016-03-17 15:09:34 -07:00
mmzone.c	mm, page_alloc: inline the fast path of the zonelist iterator	2016-05-19 19:12:14 -07:00
mprotect.c	mm: thp: check pmd_trans_unstable() after split_huge_pmd()	2016-07-26 16:19:19 -07:00
mremap.c	mm: thp: check pmd_trans_unstable() after split_huge_pmd()	2016-07-26 16:19:19 -07:00
msync.c
nobootmem.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
nommu.c	mm: introduce fault_env	2016-07-26 16:19:19 -07:00
oom_kill.c	mm, oom: fix uninitialized ret in task_will_free_mem()	2016-08-11 16:58:14 -07:00
page_alloc.c	mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator	2016-09-01 17:52:01 -07:00
page_counter.c
page_ext.c	mm: use early_pfn_to_nid in page_ext_init	2016-05-27 14:49:37 -07:00
page_idle.c	mm, vmscan: move lru_lock to the node	2016-07-28 16:07:41 -07:00
page_io.c	mm: make __swap_writepage() use bio_set_op_attrs()	2016-08-07 14:41:02 -06:00
page_isolation.c	mm/page_isolation: clean up confused code	2016-07-26 16:19:19 -07:00
page_owner.c	mm/page_owner: use stackdepot to store stacktrace	2016-07-26 16:19:19 -07:00
page_poison.c	mm: check the return value of lookup_page_ext for all call sites	2016-06-03 15:06:22 -07:00
page-writeback.c	mm: remove reclaim and compaction retry approximations	2016-07-28 16:07:41 -07:00
pagewalk.c	thp: rename split_huge_page_pmd() to split_huge_pmd()	2016-01-15 17:56:32 -08:00
percpu-km.c	mm: percpu: use pr_fmt to prefix output	2016-03-17 15:09:34 -07:00
percpu-vm.c
percpu.c	percpu: fix synchronization between synchronous map extension and chunk destruction	2016-05-25 11:48:25 -04:00
pgtable-generic.c	mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range	2016-03-17 15:09:34 -07:00
process_vm_access.c	mm/gup: Introduce get_user_pages_remote()	2016-02-16 10:04:09 +01:00
quicklist.c	fix Christoph's email addresses	2016-03-17 15:09:34 -07:00
readahead.c	mm: silently skip readahead for DAX inodes	2016-08-26 17:39:35 -07:00
rmap.c	rmap: fix compound check logic in page_remove_file_rmap	2016-08-10 16:40:56 -07:00
shmem.c	thp: move shmem_huge_enabled() outside of SYSFS ifdef	2016-08-10 16:40:56 -07:00
slab_common.c	mm: charge/uncharge kmemcg from generic page allocator paths	2016-07-26 16:19:19 -07:00
slab.c	Implements HARDENED_USERCOPY verification of copy_to_user/copy_from_user	2016-08-08 14:48:14 -07:00
slab.h	mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB	2016-07-28 16:07:41 -07:00
slob.c	mm: slab: free kmem_cache_node after destroy sysfs file	2016-02-18 16:23:24 -08:00
slub.c	mm/slub.c: run free_partial() outside of the kmem_cache_node->list_lock	2016-08-10 16:40:56 -07:00
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_cgroup.c	mm: convert printk(KERN_<LEVEL> to pr_<level>	2016-03-17 15:09:34 -07:00
swap_state.c	mm: move most file-based accounting to the node	2016-07-28 16:07:41 -07:00
swap.c	mm, pagevec: release/reacquire lru_lock on pgdat change	2016-07-28 16:07:41 -07:00
swapfile.c	mm, frontswap: convert frontswap_enabled to static key	2016-07-26 16:19:19 -07:00
truncate.c	truncate: handle file thp	2016-07-26 16:19:19 -07:00
usercopy.c	usercopy: fix overlap check for kernel text	2016-08-22 19:10:51 -07:00
userfaultfd.c	mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros	2016-04-04 10:41:08 -07:00
util.c	mm: move most file-based accounting to the node	2016-07-28 16:07:41 -07:00
vmacache.c
vmalloc.c	mm: charge/uncharge kmemcg from generic page allocator paths	2016-07-26 16:19:19 -07:00
vmpressure.c	mm/vmpressure.c: fix subtree pressure detection	2016-02-03 08:28:43 -08:00
vmscan.c	mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator	2016-09-01 17:52:01 -07:00
vmstat.c	mm: remove reclaim and compaction retry approximations	2016-07-28 16:07:41 -07:00
workingset.c	mm, workingset: make working set detection node-aware	2016-07-28 16:07:41 -07:00
z3fold.c	mm/z3fold.c: avoid modifying HEADLESS page and minor cleanup	2016-06-03 16:02:55 -07:00
zbud.c	mm/zbud.c: use list_last_entry() instead of list_tail_entry()	2016-01-15 11:40:52 -08:00
zpool.c
zsmalloc.c	zsmalloc: Delete an unnecessary check before the function call "iput"	2016-07-28 16:07:41 -07:00
zswap.c	mm/zswap: use workqueue to destroy pool	2016-05-20 17:58:30 -07:00