alistair23-linux/mm
Uladzislau Rezki d8f117abb3 z3fold: fix use-after-free when freeing handles
free_handle() for a foreign handle may race with inter-page compaction,
what can lead to memory corruption.

To avoid that, take write lock not read lock in free_handle to be
synchronized with __release_z3fold_page().

For example KASAN can detect it:

  ==================================================================
  BUG: KASAN: use-after-free in LZ4_decompress_safe+0x2c4/0x3b8
  Read of size 1 at addr ffffffc976695ca3 by task GoogleApiHandle/4121

  CPU: 0 PID: 4121 Comm: GoogleApiHandle Tainted: P S         OE     4.19.81-perf+ #162
  Hardware name: Sony Mobile Communications. PDX-203(KONA) (DT)
  Call trace:
     LZ4_decompress_safe+0x2c4/0x3b8
     lz4_decompress_crypto+0x3c/0x70
     crypto_decompress+0x58/0x70
     zcomp_decompress+0xd4/0x120
     ...

Apart from that, initialize zhdr->mapped_count in init_z3fold_page() and
remove "newpage" variable because it is not used anywhere.

Signed-off-by: Uladzislau Rezki <uladzislau.rezki@sony.com>
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Raymond Jennings <shentino@gmail.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200520082100.28876-1-vitaly.wool@konsulko.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-23 10:26:32 -07:00
..
kasan kasan: disable branch tracing for core runtime 2020-05-23 10:26:31 -07:00
backing-dev.c bdi: add a ->dev_name field to struct backing_dev_info 2020-05-09 16:07:57 -06:00
balloon_compaction.c
cleancache.c
cma.c mm: cma: NUMA node interface 2020-04-10 15:36:21 -07:00
cma.h
cma_debug.c
compaction.c mm/compaction: add missing annotation for compact_lock_irqsave 2020-04-07 10:43:41 -07:00
debug.c mm: dump_page(): additional diagnostics for huge pinned pages 2020-04-02 09:35:27 -07:00
debug_page_ref.c
dmapool.c mm/dmapool.c: micro-optimisation remove unnecessary branch 2020-04-07 10:43:42 -07:00
early_ioremap.c
fadvise.c
failslab.c
filemap.c mm: huge tmpfs: try to split_huge_page() when punching hole 2020-04-07 10:43:41 -07:00
frame_vector.c
frontswap.c
gup.c mm/gup: fix fixup_user_fault() on multiple retries 2020-05-14 10:00:35 -07:00
gup_benchmark.c mm/gup_benchmark: support pin_user_pages() and related calls 2020-04-02 09:35:27 -07:00
highmem.c
hmm.c mm/hmm: return error for non-vma snapshots 2020-03-30 16:58:36 -03:00
huge_memory.c userfaultfd: wp: support swap and page migration 2020-04-07 10:43:39 -07:00
hugetlb.c mm/hugetlb: fix a addressing exception caused by huge_pte_offset 2020-04-21 11:11:55 -07:00
hugetlb_cgroup.c mm: use fallthrough; 2020-04-07 10:43:41 -07:00
hwpoison-inject.c
init-mm.c
internal.h mm: add function __putback_isolated_page 2020-04-07 10:43:38 -07:00
interval_tree.c
Kconfig libnvdimm for 5.7 2020-04-08 21:03:40 -07:00
Kconfig.debug
khugepaged.c khugepaged: skip collapse if uffd-wp detected 2020-04-07 10:43:39 -07:00
kmemleak-test.c
kmemleak.c mm/kmemleak.c: use address-of operator on section symbols 2020-04-02 09:35:26 -07:00
ksm.c mm/ksm: fix NULL pointer dereference when KSM zero page is enabled 2020-04-21 11:11:55 -07:00
list_lru.c mm: use fallthrough; 2020-04-07 10:43:41 -07:00
maccess.c
madvise.c mm: check that mm is still valid in madvise() 2020-04-24 13:28:03 -07:00
Makefile mm: introduce Reported pages 2020-04-07 10:43:38 -07:00
mapping_dirty_helpers.c mm/mapping_dirty_helpers: update huge page-table entry callbacks 2020-04-02 09:35:29 -07:00
memblock.c mm: cma: NUMA node interface 2020-04-10 15:36:21 -07:00
memcontrol.c mm, memcg: fix error return value of mem_cgroup_css_alloc() 2020-05-07 19:27:20 -07:00
memfd.c
memory-failure.c mm: code cleanup for MADV_FREE 2020-04-07 10:43:38 -07:00
memory.c mm/memory.c: add vm_insert_pages() 2020-04-10 15:36:21 -07:00
memory_hotplug.c mm/memory_hotplug: add pgprot_t to mhp_params 2020-04-10 15:36:21 -07:00
mempolicy.c libnvdimm for 5.7 2020-04-08 21:03:40 -07:00
mempool.c
memremap.c mm/memremap: set caching mode for PCI P2PDMA memory to WC 2020-04-10 15:36:21 -07:00
memtest.c
migrate.c userfaultfd: wp: support swap and page migration 2020-04-07 10:43:39 -07:00
mincore.c
mlock.c
mm_init.c mm/mm_init.c: clean code. Use BUILD_BUG_ON when comparing compile time constant 2020-04-07 10:43:41 -07:00
mmap.c mm/vma: introduce VM_ACCESS_FLAGS 2020-04-10 15:36:21 -07:00
mmu_context.c
mmu_gather.c
mmu_notifier.c mm/mmu_notifier: silence PROVE_RCU_LIST warnings 2020-03-21 18:56:06 -07:00
mmzone.c
mprotect.c mm/vma: introduce VM_ACCESS_FLAGS 2020-04-10 15:36:21 -07:00
mremap.c userfaultfd: fix remap event with MREMAP_DONTUNMAP 2020-05-14 10:00:35 -07:00
msync.c
nommu.c x86/mm: split vmalloc_sync_all() 2020-03-21 18:56:06 -07:00
oom_kill.c
page-writeback.c mm/gup/writeback: add callbacks for inaccessible pages 2020-04-02 09:35:27 -07:00
page_alloc.c mm: limit boost_watermark on small zones 2020-05-07 19:27:21 -07:00
page_counter.c mm, memcg: prevent memory.min load/store tearing 2020-04-02 09:35:29 -07:00
page_ext.c mm/page_ext.c: drop pfn_present() check when onlining 2020-04-07 10:43:40 -07:00
page_idle.c
page_io.c
page_isolation.c mm: add function __putback_isolated_page 2020-04-07 10:43:38 -07:00
page_owner.c
page_poison.c
page_reporting.c mm/page_reporting: add budget limit on how many pages can be reported per pass 2020-04-07 10:43:39 -07:00
page_reporting.h mm: introduce Reported pages 2020-04-07 10:43:38 -07:00
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c percpu: update copyright emails to dennis@kernel.org 2020-04-01 10:09:12 -07:00
percpu-vm.c
percpu.c percpu: make pcpu_alloc() aware of current gfp context 2020-05-07 19:27:21 -07:00
pgtable-generic.c
process_vm_access.c mm: docs: Fix a comment in process_vm_rw_core 2020-03-25 10:04:01 -05:00
ptdump.c
readahead.c
rmap.c mm: prevent a warning when casting void* -> enum 2020-04-07 10:43:41 -07:00
rodata_test.c
shmem.c mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path 2020-04-21 11:11:56 -07:00
shuffle.c mm: adjust shuffle code to allow for future coalescing 2020-04-07 10:43:38 -07:00
shuffle.h mm: adjust shuffle code to allow for future coalescing 2020-04-07 10:43:38 -07:00
slab.c
slab.h mm: kmem: rename (__)memcg_kmem_(un)charge_memcg() to __memcg_kmem_(un)charge() 2020-04-02 09:35:28 -07:00
slab_common.c mm, slab_common: fix a typo in comment "eariler"->"earlier" 2020-04-10 15:36:20 -07:00
slob.c
slub.c mm/slub: fix incorrect interpretation of s->offset 2020-05-07 19:27:20 -07:00
sparse-vmemmap.c
sparse.c mm/sparse.c: move subsection_map related functions together 2020-04-07 10:43:40 -07:00
swap.c mm: huge tmpfs: try to split_huge_page() when punching hole 2020-04-07 10:43:41 -07:00
swap_cgroup.c
swap_slots.c mm/swap_slots.c: assign|reset cache slot by value directly 2020-04-02 09:35:27 -07:00
swap_state.c mm/swap_state.c: use the same way to count page in [add_to|delete_from]_swap_cache 2020-04-02 09:35:28 -07:00
swapfile.c proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
truncate.c
usercopy.c
userfaultfd.c userfaultfd: wp: support write protection for userfault vma range 2020-04-07 10:43:39 -07:00
util.c
vmacache.c
vmalloc.c vmalloc: fix remap_vmalloc_range() bounds checks 2020-04-21 11:11:56 -07:00
vmpressure.c mm: vmpressure: use mem_cgroup_is_root API 2020-04-02 09:35:31 -07:00
vmscan.c mm/vmscan: remove unnecessary argument description of isolate_lru_pages() 2020-05-07 19:27:21 -07:00
vmstat.c mm, thp: track fallbacks due to failed memcg charges separately 2020-04-07 10:43:38 -07:00
workingset.c
z3fold.c z3fold: fix use-after-free when freeing handles 2020-05-23 10:26:32 -07:00
zbud.c
zpool.c
zsmalloc.c mm: use fallthrough; 2020-04-07 10:43:41 -07:00
zswap.c mm/zswap: allow setting default status, compressor and allocator in Kconfig 2020-04-07 10:43:41 -07:00