Joel Fernandes 52193857e2 BACKPORT: mm: Add an F_SEAL_FUTURE_WRITE seal to memfd ... Android uses ashmem for sharing memory regions. We are looking forward to migrating all usecases of ashmem to memfd so that we can possibly remove the ashmem driver in the future from staging while also benefiting from using memfd and contributing to it. Note staging drivers are also not ABI and generally can be removed at anytime. One of the main usecases Android has is the ability to create a region and mmap it as writeable, then add protection against making any "future" writes while keeping the existing already mmap'ed writeable-region active. This allows us to implement a usecase where receivers of the shared memory buffer can get a read-only view, while the sender continues to write to the buffer. See CursorWindow documentation in Android for more details: https://developer.android.com/reference/android/database/CursorWindow This usecase cannot be implemented with the existing F_SEAL_WRITE seal. To support the usecase, this patch adds a new F_SEAL_FUTURE_WRITE seal which prevents any future mmap and write syscalls from succeeding while keeping the existing mmap active. Verified with test program at: https://lore.kernel.org/patchwork/patch/1008117/ Backport link: https://lore.kernel.org/patchwork/patch/1014892/ Bug: 113362644 Change-Id: If7424db3b64372932d455f0219cd9df613fec1d4 Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Joel Fernandes <joelaf@google.com>		2020-12-14 17:10:31 +01:00
..
backing-dev.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
bootmem.c	mm: sparse: fix usemap allocation above node descriptor section	2016-10-29 23:12:12 +08:00
bounce.c
cleancache.c
compaction.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
debug-pagealloc.c
dmapool.c	mm: dmapool: use provided gfp flags for all dma_alloc_coherent() calls	2012-12-17 10:37:44 -08:00
fadvise.c	mm/fadvise.c: drain all pagevecs if POSIX_FADV_DONTNEED fails to discard all pages	2013-02-28 06:59:01 -08:00
failslab.c
filemap.c	lib/radix-tree.c: make radix_tree_node_alloc() work correctly within interrupt	2020-12-07 21:02:05 +03:00
filemap_xip.c	mm: kill vma flag VM_CAN_NONLINEAR	2020-11-29 16:11:40 +03:00
fremap.c	mm: kill vma flag VM_CAN_NONLINEAR	2020-11-29 16:11:40 +03:00
highmem.c	mm: highmem: don't treat PKMAP_ADDR(LAST_PKMAP) as a highmem address	2014-06-11 12:04:22 -07:00
huge_memory.c	mm, thp: fix collapsing of hugepages on madvise	2015-02-02 17:05:07 +08:00
hugetlb.c	Fix incomplete backport of commit 0f792cf949a0	2016-10-26 23:15:44 +08:00
hwpoison-inject.c
init-mm.c
internal.h	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
Kconfig	BACKPORT: mm/zsmalloc: add statistics support	2018-01-01 21:27:09 +03:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c	mm: kmemleak: allow safe memory scanning during kmemleak disabling	2015-10-22 09:20:06 +08:00
ksm.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
maccess.c
madvise.c	mm/fs: route MADV_REMOVE to FALLOC_FL_PUNCH_HOLE	2020-12-07 21:00:58 +03:00
Makefile	BACKPORT: mm/zpool: implement common zpool api to zbud/zsmalloc	2018-01-01 21:27:00 +03:00
memblock.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
memcontrol.c	shmem: replace page if mapping excludes its zone	2020-12-07 20:57:06 +03:00
memory-failure.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
memory.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
memory_hotplug.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
mempolicy.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
mempool.c
migrate.c	BACKPORT: Sanitize 'move_pages()' permission checks	2018-01-13 17:13:40 +03:00
mincore.c	swap: make each swap partition have one address_space	2018-01-01 22:02:05 +03:00
mlock.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
mm_init.c
mmap.c	mm: allow drivers to prevent new writable mappings	2020-12-07 21:08:09 +03:00
mmu_context.c
mmu_notifier.c	mm: mmu_notifier: re-fix freed page still mapped in secondary MMU	2013-06-07 12:49:25 -07:00
mmzone.c
mprotect.c	mm: add a field to store names for private anonymous memory	2013-10-11 10:02:06 -07:00
mremap.c
msync.c
nobootmem.c	memblock: free allocated memblock_reserved_regions later	2012-07-16 09:04:45 -07:00
nommu.c	mm: kill vma flag VM_CAN_NONLINEAR	2020-11-29 16:11:40 +03:00
oom_kill.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
page-writeback.c	mm: fix calculation of dirtyable memory	2016-10-29 23:12:16 +08:00
page_alloc.c	mm/page_alloc.c: use '__paginginit' instead of '__init'	2017-12-27 17:13:39 +03:00
page_cgroup.c	cgroup/kmemleak: add kmemleak_free() for cgroup deallocations.	2015-02-02 17:05:07 +08:00
page_io.c
page_isolation.c	mm: page_isolation: MIGRATE_CMA isolation functions added	2013-02-27 18:14:02 -08:00
pagewalk.c	mm/pagewalk.c: walk_page_range should avoid VM_PFNMAP areas	2013-06-07 12:49:28 -07:00
percpu-km.c
percpu-vm.c	percpu: perform tlb flush after pcpu_map_pages() failure	2014-12-01 18:02:23 +08:00
percpu.c	Revert "percpu: free percpu allocation info for uniprocessor system"	2015-02-02 17:04:38 +08:00
pgtable-generic.c
prio_tree.c
process_vm_access.c	Fix: compat_rw_copy_check_uvector() misuse in aio, readv, writev, and security keys	2013-03-14 11:29:51 -07:00
quicklist.c
readahead.c	mm: change initial readahead window size calculation	2016-10-29 23:12:18 +08:00
rmap.c	mm: fix anon_vma->degree underflow in anon_vma endless growing prevention	2015-04-14 17:34:04 +08:00
shmem.c	BACKPORT: mm: Add an F_SEAL_FUTURE_WRITE seal to memfd	2020-12-14 17:10:31 +01:00
slab.c	cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags	2014-12-01 18:02:38 +08:00
slob.c
slub.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
sparse-vmemmap.c
sparse.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
swap.c	swap: make each swap partition have one address_space	2018-01-01 22:02:05 +03:00
swap_state.c	mm: allow drivers to prevent new writable mappings	2020-12-07 21:08:09 +03:00
swapfile.c	vfs: make path_openat take a struct filename pointer	2018-12-07 22:28:48 +04:00
thrash.c
truncate.c	mm/fs: remove truncate_range	2020-12-07 20:57:30 +03:00
util.c	swap: make each swap partition have one address_space	2018-01-01 22:02:05 +03:00
vmalloc.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
vmscan.c	mm: new shrinker API	2020-11-29 16:11:30 +03:00
vmstat.c	Merge remote-tracking branch 'stable/linux-3.4.y' into lineage-15.1	2017-12-27 17:13:15 +03:00
zpool.c	BACKPORT: mm/zpool: add name argument to create zpool	2018-01-01 21:27:09 +03:00
zsmalloc.c	UPSTREAM: zsmalloc: fix a null pointer dereference in destroy_handle_cache()	2018-01-01 21:27:14 +03:00