android_kernel_asus_sm8350/mm
Linus Torvalds 210f96fb7e v4l2: don't fall back to follow_pfn() if pin_user_pages_fast() fails
commit 6647e76ab623b2b3fb2efe03a86e9c9046c52c33 upstream.

The V4L2_MEMORY_USERPTR interface is long deprecated and shouldn't be
used (and is discouraged for any modern v4l drivers).  And Seth Jenkins
points out that the fallback to VM_PFNMAP/VM_IO is fundamentally racy
and dangerous.

Note that it's not even a case that should trigger, since any normal
user pointer logic ends up just using the pin_user_pages_fast() call
that does the proper page reference counting.  That's not the problem
case, only if you try to use special device mappings do you have any
issues.

Normally I'd just remove this during the merge window, but since Seth
pointed out the problem cases, we really want to know as soon as
possible if there are actually any users of this odd special case of a
legacy interface.  Neither Hans nor Mauro seem to think that such
mis-uses of the old legacy interface should exist.  As Mauro says:

 "See, V4L2 has actually 4 streaming APIs:
        - Kernel-allocated mmap (usually referred simply as just mmap);
        - USERPTR mmap;
        - read();
        - dmabuf;

  The USERPTR is one of the oldest way to use it, coming from V4L
  version 1 times, and by far the least used one"

And Hans chimed in on the USERPTR interface:

 "To be honest, I wouldn't mind if it goes away completely, but that's a
  bit of a pipe dream right now"

but while removing this legacy interface entirely may be a pipe dream we
can at least try to remove the unlikely (and actively broken) case of
using special device mappings for USERPTR accesses.

This replaces it with a WARN_ONCE() that we can remove once we've
hopefully confirmed that no actual users exist.

NOTE! Longer term, this means that a 'struct frame_vector' only ever
contains proper page pointers, and all the games we have with converting
them to pages can go away (grep for 'frame_vector_to_pages()' and the
uses of 'vec->is_pfns').  But this is just the first step, to verify
that this code really is all dead, and do so as quickly as possible.

Reported-by: Seth Jenkins <sethjenkins@google.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:23:06 +01:00
..
kasan kasan: fix incorrect arguments passing in kasan_add_zero_shadow 2021-01-27 11:47:53 +01:00
backing-dev.c mm: bdi: initialize bdi_min_ratio when bdi is unregistered 2021-12-14 14:49:00 +01:00
balloon_compaction.c mm/balloon_compaction: suppress allocation warnings 2019-09-04 07:42:01 -04:00
cleancache.c Driver Core and debugfs changes for 5.3-rc1 2019-07-12 12:24:03 -07:00
cma_debug.c mm/cma_debug.c: fix the break condition in cma_maxchunk_get() 2019-05-14 09:47:45 -07:00
cma.c cma: don't quit at first error when activating reserved areas 2020-09-03 11:26:51 +02:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.c mm, compaction: fast_find_migrateblock() should return pfn in the target zone 2022-06-14 18:11:46 +02:00
debug_page_ref.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug.c mm/debug.c: always print flags in dump_page() 2020-03-05 16:43:51 +01:00
dmapool.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2017-12-11 14:54:44 +01:00
fadvise.c fs: Export generic_fadvise() 2019-08-30 22:43:58 -07:00
failslab.c mm/failslab.c: by default, do not fail allocations with direct reclaim only 2019-07-12 11:05:43 -07:00
filemap.c mm: fs: initialize fsdata passed to write_begin/write_end interface 2022-11-25 17:42:22 +01:00
frame_vector.c v4l2: don't fall back to follow_pfn() if pin_user_pages_fast() fails 2022-12-08 11:23:06 +01:00
frontswap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482 2019-06-19 17:09:52 +02:00
gup_benchmark.c mm/gup: fix memory leak in __gup_benchmark_ioctl 2020-01-09 10:20:00 +01:00
gup.c mm/gup: fix gup_fast with dynamic page table folding 2020-10-01 13:18:24 +02:00
highmem.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
hmm.c pagewalk: separate function pointers from iterator data 2019-09-07 04:28:04 -03:00
huge_memory.c mm/huge_memory.c: don't discard hugepage if other processes are mapping it 2021-07-14 16:53:47 +02:00
hugetlb_cgroup.c mm: hugetlb: switch to css_tryget() in hugetlb_cgroup_charge_cgroup() 2019-11-15 18:34:00 -08:00
hugetlb.c mm,hugetlb: take hugetlb_lock before decrementing h->resv_huge_pages 2022-11-03 23:56:54 +09:00
hwpoison-inject.c hwpoison-inject: no need to check return value of debugfs_create functions 2019-06-03 15:39:40 +02:00
init-mm.c mm/init-mm.c: include <linux/mman.h> for vm_committed_as_batch 2019-10-19 06:32:32 -04:00
internal.h mm/thp: fix vma_address() if virtual address below file offset 2021-06-30 08:47:52 -04:00
interval_tree.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248 2019-06-19 17:09:08 +02:00
Kconfig mm/zsmalloc.c: drop ZSMALLOC_PGTABLE_MAPPING 2020-12-16 10:56:59 +01:00
Kconfig.debug mm, page_owner, debug_pagealloc: save and dump freeing stack trace 2019-09-24 15:54:08 -07:00
khugepaged.c khugepaged: fix wrong result value for trace_mm_collapse_huge_page_isolate() 2021-05-19 10:08:27 +02:00
kmemleak-test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
kmemleak.c Revert "mm: kmemleak: take a full lowmem check in kmemleak_*_phys()" 2022-09-15 12:04:49 +02:00
ksm.c ksm: fix potential missing rmap_item for stable_node 2021-05-19 10:08:27 +02:00
list_lru.c mm: list_lru: set shrinker map bit when child nr_items is not zero 2020-12-11 13:23:31 +01:00
maccess.c uaccess: Add non-pagefault user-space write function 2020-01-17 19:48:40 +01:00
madvise.c mm: fix madivse_pageout mishandling on non-LRU page 2022-10-05 10:37:43 +02:00
Makefile mm: silence -Woverride-init/initializer-overrides 2019-09-24 15:54:10 -07:00
memblock.c memblock: use kfree() to release kmalloced memblock regions 2022-03-02 11:41:18 +01:00
memcontrol.c mm/memcontrol: return 1 from cgroup.memory __setup() handler 2022-04-15 14:18:29 +02:00
memfd.c memfd: fix F_SEAL_WRITE after shmem huge page allocated 2022-03-08 19:07:49 +01:00
memory_hotplug.c mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range() 2021-09-22 12:26:43 +02:00
memory-failure.c mm/memory-failure: make sure wait for page writeback in memory_failure 2021-06-23 14:41:23 +02:00
memory.c mm: hugetlb: fix missing cache flush in copy_huge_page_from_user() 2022-05-15 19:54:47 +02:00
mempolicy.c mm/mempolicy: fix uninit-value in mpol_rebind_policy() 2022-07-29 17:14:16 +02:00
mempool.c docs/core-api/mm: fix return value descriptions in mm/ 2019-03-05 21:07:20 -08:00
memremap.c mm/memory_hotplug: shrink zones when offlining memory 2020-01-09 10:19:56 +01:00
memtest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.c mm/migrate_device.c: flush TLB while holding PTL 2022-10-05 10:37:43 +02:00
mincore.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mlock.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
mm_init.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
mmap.c mm: Fix TLB flush for not-first PFNMAP mappings in unmap_region() 2022-09-20 12:28:00 +02:00
mmu_context.c mm: fix kthread_use_mm() vs TLB invalidate 2020-09-03 11:26:51 +02:00
mmu_gather.c mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush 2020-02-11 04:35:42 -08:00
mmu_notifier.c mm/mmu_notifiers: use the right return code for WARN_ON 2019-11-06 08:47:50 -08:00
mmzone.c arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 19:54:46 +02:00
mprotect.c mm, numa: fix bad pmd by atomically check for pmd_trans_huge when marking page tables prot_numa 2020-03-12 13:00:19 +01:00
mremap.c mm/mremap: hold the rmap lock in write mode when moving page table entries. 2022-08-25 11:17:20 +02:00
msync.c mm: untag user pointers passed to memory syscalls 2019-09-25 17:51:41 -07:00
nommu.c x86/mm: split vmalloc_sync_all() 2020-03-25 08:25:58 +01:00
oom_kill.c oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup 2022-04-27 13:50:48 +02:00
page_alloc.c mm: prevent page_frag_alloc() from corrupting the memory 2022-10-05 10:37:43 +02:00
page_counter.c mm/page_counter.c: fix protection usage propagation 2020-08-21 13:05:27 +02:00
page_ext.c mm, page_owner: fix off-by-one error in __set_page_owner_handle() 2019-10-14 15:04:00 -07:00
page_idle.c mm/page_idle.c: fix oops because end_pfn is larger than max_pfn 2019-06-29 16:43:45 +08:00
page_io.c mm: fix unexpected zeroed page mapping with zram swap 2022-05-12 12:23:48 +02:00
page_isolation.c mm/memory_hotplug: drain per-cpu pages again during memory offline 2020-09-23 12:40:47 +02:00
page_owner.c mm/page_owner: change split_page_owner to take a count 2020-10-29 09:57:52 +01:00
page_poison.c mm/page_poison.c: fix a typo in a comment 2019-09-24 15:54:08 -07:00
page_vma_mapped.c mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk() 2021-06-30 08:47:55 -04:00
page-writeback.c mm/page-writeback.c: avoid potential division by zero in wb_min_max_ratio() 2020-01-23 08:22:41 +01:00
pagewalk.c mm: pagewalk: Fix race between unmap and page walker 2022-10-15 07:54:36 +02:00
percpu-internal.h percpu: convert chunk hints to be based on pcpu_block_md 2019-03-13 12:25:31 -07:00
percpu-km.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-stats.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-vm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu.c percpu: fix first chunk size calculation for populated bitmap 2020-09-23 12:40:45 +02:00
pgtable-generic.c mm/thp: fix __split_huge_pmd_locked() on shmem migration entry 2021-06-30 08:47:52 -04:00
process_vm_access.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
readahead.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
rmap.c mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse 2022-09-05 10:27:46 +02:00
rodata_test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
shmem.c shmem: fix a race between shmem_unused_huge_shrink and shmem_evict_inode 2022-01-27 09:19:29 +01:00
shuffle.c mm/shuffle: don't move pages between zones and don't read garbage memmaps 2020-09-03 11:26:51 +02:00
shuffle.h mm: maintain randomization of page free lists 2019-05-14 19:52:48 -07:00
slab_common.c mm: slab: fix kmem_cache_create failed when sysfs node not destroyed 2021-07-25 14:35:14 +02:00
slab.c mm, debug_pagealloc: don't rely on static keys too early 2020-01-23 08:22:40 +01:00
slab.h mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag 2021-11-26 10:47:21 +01:00
slob.c mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two) 2019-10-07 15:47:20 -07:00
slub.c mm/slub: fix to return errno if kmalloc() fails 2022-09-28 11:04:04 +02:00
sparse-vmemmap.c mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap() 2019-07-18 17:08:07 -07:00
sparse.c mm/sparse: add the missing sparse_buffer_fini() in error branch 2021-05-14 09:44:32 +02:00
swap_cgroup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swap_slots.c mm, swap, get_swap_pages: use entry_size instead of cluster in parameter 2018-08-22 10:52:44 -07:00
swap_state.c mm/swap_state: fix a data race in swapin_nr_pages 2020-10-01 13:18:08 +02:00
swap.c mm: introduce MADV_COLD 2019-09-25 17:51:41 -07:00
swapfile.c swap: fix swapfile read/write offset 2021-03-07 12:20:49 +01:00
truncate.c mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page() 2021-06-30 08:47:53 -04:00
usercopy.c mm/usercopy: return 1 from hardened_usercopy __setup() handler 2022-04-15 14:18:30 +02:00
userfaultfd.c mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic() 2022-05-15 19:54:47 +02:00
util.c random: move randomize_page() into mm where it belongs 2022-06-22 14:11:17 +02:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-13 15:18:04 -10:00
vmalloc.c mm/vunmap: add cond_resched() in vunmap_pmd_range 2020-09-03 11:26:52 +02:00
vmpressure.c mm/vmpressure.c: fix a signedness bug in vmpressure_register_event() 2019-10-07 15:47:19 -07:00
vmscan.c mm,vmscan: fix divide by zero in get_scan_count 2021-09-22 12:26:37 +02:00
vmstat.c arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 2022-05-15 19:54:46 +02:00
workingset.c mm: workingset: fix vmstat counters for shadow nodes 2019-08-13 16:06:52 -07:00
z3fold.c mm/z3fold: fix potential memory leak in z3fold_destroy_pool() 2021-07-14 16:53:47 +02:00
zbud.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
zpool.c zpool: add malloc_support_movable to zpool_driver 2019-09-24 15:54:12 -07:00
zsmalloc.c zsmalloc: fix races between asynchronous zspage free and page migration 2022-06-06 08:33:50 +02:00
zswap.c zswap: do not map same object twice 2019-09-24 15:54:12 -07:00