kernel_optimize_test/mm
Yang Shi 6d67b2a73b mm: khugepaged: skip huge page collapse for special files
commit a4aeaa06d45e90f9b279f0b09de84bd00006e733 upstream.

The read-only THP for filesystems will collapse THP for files opened
readonly and mapped with VM_EXEC.  The intended usecase is to avoid TLB
misses for large text segments.  But it doesn't restrict the file types
so a THP could be collapsed for a non-regular file, for example, block
device, if it is opened readonly and mapped with EXEC permission.  This
may cause bugs, like [1] and [2].

This is definitely not the intended usecase, so just collapse THP for
regular files in order to close the attack surface.

[shy828301@gmail.com: fix vm_file check [3]]

Link: https://lore.kernel.org/lkml/CACkBjsYwLYLRmX8GpsDpMthagWOjWWrNxqY6ZLNQVr6yx+f5vA@mail.gmail.com/ [1]
Link: https://lore.kernel.org/linux-mm/000000000000c6a82505ce284e4c@google.com/ [2]
Link: https://lkml.kernel.org/r/CAHbLzkqTW9U3VvTu1Ki5v_cLRC9gHW+znBukg_ycergE0JWj-A@mail.gmail.com [3]
Link: https://lkml.kernel.org/r/20211027195221.3825-1-shy828301@gmail.com
Fixes: 99cb0dbd47 ("mm,thp: add read-only THP support for (non-shmem) FS")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reported-by: Hao Sun <sunhao.th@gmail.com>
Reported-by: syzbot+aae069be1de40fb11825@syzkaller.appspotmail.com
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Andrea Righi <andrea.righi@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-06 14:10:09 +01:00
..
kasan
backing-dev.c
balloon_compaction.c
cleancache.c
cma_debug.c
cma.c
cma.h
compaction.c mm, compaction: make fast_isolate_freepages() stay within zone 2021-03-04 11:38:38 +01:00
debug_page_ref.c
debug_vm_pgtable.c mm/debug_vm_pgtable: ensure THP availability via has_transparent_hugepage() 2021-07-14 16:56:13 +02:00
debug.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c
frame_vector.c
frontswap.c
gup_benchmark.c
gup.c mm/gup: fix try_grab_compound_head() race with split_huge_page() 2021-07-14 16:55:42 +02:00
highmem.c
hmm.c mm/hmm: bypass devmap pte when all pfn requested flags are fulfilled 2021-09-18 13:40:36 +02:00
huge_memory.c mm/userfaultfd: fix uffd-wp special cases for fork() 2021-07-25 14:36:18 +02:00
hugetlb_cgroup.c hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings 2021-03-30 14:31:54 +02:00
hugetlb.c hugetlb: fix hugetlb cgroup refcounting during vma split 2021-09-18 13:40:36 +02:00
hwpoison-inject.c
init-mm.c
internal.h mm/thp: fix vma_address() if virtual address below file offset 2021-06-30 08:47:27 -04:00
interval_tree.c
ioremap.c
Kconfig
Kconfig.debug
khugepaged.c mm: khugepaged: skip huge page collapse for special files 2021-11-06 14:10:09 +01:00
kmemleak.c
ksm.c ksm: fix potential missing rmap_item for stable_node 2021-05-19 10:13:07 +02:00
list_lru.c
maccess.c
madvise.c mm/madvise: replace ptrace attach requirement for process_madvise 2021-03-17 17:06:37 +01:00
Makefile
mapping_dirty_helpers.c
memblock.c memblock: make for_each_mem_range() traverse MEMBLOCK_HOTPLUG regions 2021-07-28 14:35:46 +02:00
memcontrol.c mm: memcg/slab: properly set up gfp flags for objcg pointer array 2021-07-14 16:56:14 +02:00
memfd.c
memory_hotplug.c mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range() 2021-09-22 12:27:59 +02:00
memory-failure.c mm,hwpoison: return -EBUSY when migration fails 2021-07-19 09:44:56 +02:00
memory.c mm/userfaultfd: fix uffd-wp special cases for fork() 2021-07-25 14:36:18 +02:00
mempolicy.c
mempool.c
memremap.c mm: fix memory_failure() handling of dax-namespace metadata 2021-03-04 11:38:21 +01:00
memtest.c
migrate.c mm, thp: use head page in __migration_entry_wait() 2021-06-30 08:47:26 -04:00
mincore.c
mlock.c
mm_init.c
mmap.c
mmu_gather.c
mmu_notifier.c mm/mmu_notifiers: ensure range_end() is paired with range_start() 2021-03-30 14:32:06 +02:00
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c
page_alloc.c mm/page_alloc: speed up the iteration of max_order 2021-09-12 08:58:26 +02:00
page_counter.c
page_ext.c
page_idle.c
page_io.c swap: fix swapfile read/write offset 2021-03-07 12:34:15 +01:00
page_isolation.c
page_owner.c
page_poison.c
page_reporting.c
page_reporting.h
page_vma_mapped.c mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk() 2021-06-30 08:47:29 -04:00
page-writeback.c
pagewalk.c
percpu-internal.h percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
percpu-km.c
percpu-stats.c percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
percpu-vm.c
percpu.c percpu: make pcpu_nr_empty_pop_pages per chunk type 2021-04-14 08:42:03 +02:00
pgalloc-track.h
pgtable-generic.c mm/thp: fix __split_huge_pmd_locked() on shmem migration entry 2021-06-30 08:47:26 -04:00
process_vm_access.c
ptdump.c mm: ptdump: fix build failure 2021-04-21 13:00:57 +02:00
readahead.c
rmap.c mm/thp: fix page_address_in_vma() on file THP tails 2021-06-30 08:47:27 -04:00
rodata_test.c
shmem.c Revert "mm/shmem: fix shmem_swapin() race with swapoff" 2021-07-25 14:36:20 +02:00
shuffle.c
shuffle.h
slab_common.c mm/slub: fix redzoning for small allocations 2021-06-23 14:42:54 +02:00
slab.c mm/sl?b.c: remove ctor argument from kmem_cache_flags 2021-05-14 09:50:45 +02:00
slab.h mm: memcg/slab: properly set up gfp flags for objcg pointer array 2021-07-14 16:56:14 +02:00
slob.c
slub.c mm, slub: fix incorrect memcg slab count for bulk free 2021-10-27 09:56:53 +02:00
sparse-vmemmap.c
sparse.c mm/sparse: add the missing sparse_buffer_fini() in error branch 2021-05-14 09:50:45 +02:00
swap_cgroup.c
swap_slots.c
swap_state.c
swap.c
swapfile.c mm/swap: fix pte_same_as_swp() not removing uffd-wp bit when compare 2021-06-23 14:42:53 +02:00
truncate.c mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page() 2021-06-30 08:47:27 -04:00
usercopy.c
userfaultfd.c
util.c mm: don't allow oversized kvmalloc() calls 2021-10-06 15:56:03 +02:00
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c mm,vmscan: fix divide by zero in get_scan_count 2021-09-18 13:40:36 +02:00
vmstat.c
workingset.c
z3fold.c mm/z3fold: use release_z3fold_page_locked() to release locked z3fold page 2021-07-14 16:56:51 +02:00
zbud.c
zpool.c
zsmalloc.c zsmalloc: account the number of compacted pages correctly 2021-03-07 12:34:15 +01:00
zswap.c