Zach O'Keefe 16b1025eaa mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again ... commit 9319b64790 upstream. (struct dirty_throttle_control *)->thresh is an unsigned long, but is passed as the u32 divisor argument to div_u64(). On architectures where unsigned long is 64 bytes, the argument will be implicitly truncated. Use div64_u64() instead of div_u64() so that the value used in the "is this a safe division" check is the same as the divisor. Also, remove redundant cast of the numerator to u64, as that should happen implicitly. This would be difficult to exploit in memcg domain, given the ratio-based arithmetic domain_drity_limits() uses, but is much easier in global writeback domain with a BDI_CAP_STRICTLIMIT-backing device, using e.g. vm.dirty_bytes=(1<<32)*PAGE_SIZE so that dtc->thresh == (1<<32) Link: https://lkml.kernel.org/r/20240118181954.1415197-1-zokeefe@google.com Fixes: f6789593d5 ("mm/page-writeback.c: fix divide by zero in bdi_dirty_limits()") Signed-off-by: Zach O'Keefe <zokeefe@google.com> Cc: Maxim Patlasov <MPatlasov@parallels.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2024-02-23 09:12:32 +01:00
..
damon	mm/damon/core: make damon_start() waits until kdamond_fn() starts	2024-01-01 12:39:08 +00:00
kasan	kasan: disable kasan_non_canonical_hook() for HW tags	2024-01-01 12:38:52 +00:00
kfence	mm,kfence: decouple kfence from page granularity mapping judgement	2023-12-03 07:32:08 +01:00
kmsan	mm: kmsan: handle alloc failures in kmsan_vmap_pages_range_noflush()	2023-04-26 14:28:41 +02:00
backing-dev.c	writeback, cgroup: fix null-ptr-deref write in bdi_split_work_to_wbs	2023-04-26 14:28:39 +02:00
balloon_compaction.c
bootmem_info.c
cma.c	mm/cma: use nth_page() in place of direct struct page manipulation	2023-11-28 17:07:14 +00:00
cma.h
cma_debug.c
cma_sysfs.c
compaction.c	Revert "mm/compaction: fix set skip in fast_find_migrateblock"	2023-02-01 08:34:49 +01:00
debug.c
debug_page_ref.c
debug_vm_pgtable.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
folio-compat.c
frontswap.c
gup.c	mm: always expand the stack with the mmap write lock held	2023-07-01 13:16:25 +02:00
gup_test.c
gup_test.h
highmem.c
hmm.c
huge_memory.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
hugetlb.c	hugetlb: fix null-ptr-deref in hugetlb_vma_lock_write	2023-12-13 18:39:20 +01:00
hugetlb_cgroup.c
hugetlb_vmemmap.c	mm: hugetlb_vmemmap: fix a race between vmemmap pmd split	2023-09-19 12:27:56 +02:00
hugetlb_vmemmap.h
hwpoison-inject.c
init-mm.c
internal.h	mm, netfs, fscache: stop read optimisation when folio removed from pagecache	2024-01-10 17:10:31 +01:00
interval_tree.c
io-mapping.c
ioremap.c
Kconfig	mm: introduce new 'lock_mm_and_find_vma()' page fault helper	2023-07-01 13:16:24 +02:00
Kconfig.debug	mm: page_table_check: Make it dependent on EXCLUSIVE_SYSTEM_RAM	2023-06-14 11:15:29 +02:00
khugepaged.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
kmemleak.c
ksm.c	mm/ksm: fix race with VMA iteration and mm_struct teardown	2023-03-30 12:49:29 +02:00
list_lru.c
maccess.c	mm: Fix copy_from_user_nofault().	2023-06-28 11:12:17 +02:00
madvise.c	madvise:madvise_free_pte_range(): don't use mapcount() against large folio for sharing check	2023-08-30 16:11:11 +02:00
Makefile
mapping_dirty_helpers.c
memblock.c	Revert "mm: Always release pages to the buddy allocator in memblock_free_late()."	2023-02-22 12:59:50 +01:00
memcontrol.c	mm: kmem: drop __GFP_NOFAIL when allocating objcg vectors	2023-11-28 17:07:20 +00:00
memfd.c	memfd: check for non-NULL file_seals in memfd_create() syscall	2023-06-28 11:12:27 +02:00
memory-failure.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
memory-tiers.c	memory tier: release the new_memtier in find_create_memory_tier()	2023-03-10 09:34:27 +01:00
memory.c	mm: fix unmap_mapping_range high bits shift bug	2024-01-10 17:10:35 +01:00
memory_hotplug.c	mm/memory_hotplug: fix error handling in add_memory_resource()	2024-01-10 17:10:33 +01:00
mempolicy.c	mm/mempolicy: fix set_mempolicy_home_node() previous VMA pointer	2023-11-08 14:11:02 +01:00
mempool.c
memremap.c
memtest.c
migrate.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
migrate_device.c
mincore.c	mm: teach mincore_hugetlb about pte markers	2023-03-22 13:34:03 +01:00
mlock.c
mm_init.c
mm_slot.h
mmap.c	mmap: fix error paths with dup_anon_vma()	2023-11-08 14:11:03 +01:00
mmap_lock.c
mmu_gather.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c	mm, mremap: fix mremap() expanding for vma's with vm_ops->close()	2023-02-09 11:28:22 +01:00
msync.c
nommu.c	xtensa: fix lock_mm_and_find_vma in case VMA not found	2023-07-05 18:27:37 +01:00
oom_kill.c
page-writeback.c	mm/writeback: fix possible divide-by-zero in wb_dirty_limits(), again	2024-02-23 09:12:32 +01:00
page_alloc.c	mm: page_alloc: unreserve highatomic page blocks before oom	2024-01-31 16:17:03 -08:00
page_counter.c
page_ext.c
page_idle.c
page_io.c	use less confusing names for iov_iter direction initializers	2023-02-09 11:28:04 +01:00
page_isolation.c
page_owner.c
page_poison.c
page_reporting.c
page_reporting.h
page_table_check.c	mm: page_table_check: Ensure user pages are not slab pages	2023-06-14 11:15:29 +02:00
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgalloc-track.h
pgtable-generic.c
process_vm_access.c	use less confusing names for iov_iter direction initializers	2023-02-09 11:28:04 +01:00
ptdump.c
readahead.c	vfs: fix readahead(2) on block devices	2023-11-20 11:51:50 +01:00
rmap.c	mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON	2023-03-10 09:34:25 +01:00
rodata_test.c
secretmem.c
shmem.c	mm/shmem: fix race in shmem_undo_range w/THP	2023-12-20 17:00:26 +01:00
shrinker_debug.c	mm: shrinkers: fix deadlock in shrinker debugfs	2023-02-22 12:59:46 +01:00
shuffle.c
shuffle.h
slab.c	mm/slab: Fix undefined init_cache_node_node() for NUMA and !SMP	2023-03-30 12:49:23 +02:00
slab.h
slab_common.c	mm/slab_common: fix slab_caches list corruption after kmem_cache_destroy()	2023-10-06 14:57:03 +02:00
slob.c
slub.c
sparse-vmemmap.c
sparse.c	mm/sparsemem: fix race in accessing memory_section->usage	2024-01-31 16:17:02 -08:00
swap.c
swap.h
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c	mm/swap: fix swap_info_struct race between swapoff and get_swap_pages()	2023-04-13 16:55:36 +02:00
truncate.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
usercopy.c	mm: Fix copy_from_user_nofault().	2023-06-28 11:12:17 +02:00
userfaultfd.c
util.c	rcu: dump vmalloc memory info safely	2023-09-13 09:42:59 +02:00
vmalloc.c	mm/vmalloc: add a safer version of find_vm_area() for debug	2023-09-13 09:43:00 +02:00
vmpressure.c	net-memcg: Fix scope of sockmem pressure indicators	2023-09-13 09:42:33 +02:00
vmscan.c	mm: merge folio_has_private()/filemap_release_folio() call pairs	2024-01-10 17:10:31 +01:00
vmstat.c
workingset.c	mm/mglru: fix underprotected page cache	2023-12-20 17:00:26 +01:00
z3fold.c
zbud.c
zpool.c
zsmalloc.c	zsmalloc: allow only one active pool compaction context	2023-08-23 17:52:40 +02:00
zswap.c	zswap: do not shrink if cgroup may not zswap	2023-06-21 16:00:54 +02:00