Tejun Heo fbf8321238 memcg: Fix possible use-after-free in memcg_write_event_control() ... memcg_write_event_control() accesses the dentry->d_name of the specified control fd to route the write call. As a cgroup interface file can't be renamed, it's safe to access d_name as long as the specified file is a regular cgroup file. Also, as these cgroup interface files can't be removed before the directory, it's safe to access the parent too. Prior to 347c4a8747 ("memcg: remove cgroup_event->cft"), there was a call to __file_cft() which verified that the specified file is a regular cgroupfs file before further accesses. The cftype pointer returned from __file_cft() was no longer necessary and the commit inadvertently dropped the file type check with it allowing any file to slip through. With the invarients broken, the d_name and parent accesses can now race against renames and removals of arbitrary files and cause use-after-free's. Fix the bug by resurrecting the file type check in __file_cft(). Now that cgroupfs is implemented through kernfs, checking the file operations needs to go through a layer of indirection. Instead, let's check the superblock and dentry type. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: 347c4a8747 ("memcg: remove cgroup_event->cft") Cc: stable@kernel.org # v3.14+ Reported-by: Jann Horn <jannh@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2022-12-08 10:40:58 -08:00
..
damon	mm/damon/sysfs: fix wrong empty schemes assumption under online tuning in damon_sysfs_set_schemes()	2022-11-30 14:49:41 -08:00
kasan	Random number generator fixes for Linux 6.1-rc1.	2022-10-16 15:27:07 -07:00
kfence	kfence: fix stack trace pruning	2022-11-22 18:50:44 -08:00
kmsan	kmsan: core: kmsan_in_runtime() should return true in NMI context	2022-11-08 15:57:24 -08:00
backing-dev.c	mm: backing-dev: Remove the unneeded result variable	2022-09-11 20:26:02 -07:00
balloon_compaction.c	mm: Convert all PageMovable users to movable_operations	2022-08-02 12:34:03 -04:00
bootmem_info.c	bootmem: remove the vmemmap pages from kmemleak in put_page_bootmem	2022-08-28 14:02:45 -07:00
cma_debug.c	mm/cma_debug: show complete cma name in debugfs directories	2022-09-11 20:25:50 -07:00
cma_sysfs.c
cma.c	Revert "mm/cma.c: remove redundant cma_mutex lock"	2022-05-13 15:11:26 -07:00
cma.h
compaction.c	mm: migrate: fix THP's mapcount on isolation	2022-11-30 14:49:41 -08:00
debug_page_ref.c
debug_vm_pgtable.c	docs: rename Documentation/vm to Documentation/mm	2022-06-27 12:52:53 -07:00
debug.c	mm: remove the vma linked list	2022-09-26 19:46:26 -07:00
dmapool.c
early_ioremap.c
fadvise.c	riscv: compat: syscall: Add compat_sys_call_table implementation	2022-04-26 13:36:25 -07:00
failslab.c	mm: fix unexpected changes to {failslab|fail_page_alloc}.attr	2022-11-22 18:50:44 -08:00
filemap.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
folio-compat.c	mm: remove try_to_free_swap()	2022-10-03 14:02:53 -07:00
frontswap.c	frontswap: don't call ->init if no ops are registered	2022-09-26 12:14:34 -07:00
gup_test.c	mm: rename is_pinnable_page() to is_longterm_pinnable_page()	2022-07-17 17:14:27 -07:00
gup_test.h
gup.c	Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one is	2022-10-12 11:16:58 -07:00
highmem.c	highmem: fix kmap_to_page() for kmap_local_page() addresses	2022-10-12 18:51:51 -07:00
hmm.c	mm/swap: add swp_offset_pfn() to fetch PFN from swap entry	2022-09-26 19:46:05 -07:00
huge_memory.c	Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"	2022-11-08 15:57:23 -08:00
hugetlb_cgroup.c	hugetlb_cgroup: use helper for_each_hstate and hstate_index	2022-09-11 20:25:53 -07:00
hugetlb_vmemmap.c	mm: hugetlb_vmemmap: include missing linux/moduleparam.h	2022-11-08 15:57:23 -08:00
hugetlb_vmemmap.h	mm: hugetlb_vmemmap: improve hugetlb_vmemmap code readability	2022-08-08 18:06:43 -07:00
hugetlb.c	hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing	2022-11-30 14:49:40 -08:00
hwpoison-inject.c	mm/hwpoison: add __init/__exit annotations to module init/exit funcs	2022-10-03 14:03:05 -07:00
init-mm.c	mm: remove rb tree.	2022-09-26 19:46:16 -07:00
internal.h	mm/page_alloc: make boot_nodestats static	2022-10-03 14:03:30 -07:00
interval_tree.c
io-mapping.c
ioremap.c	mm: ioremap: Add ioremap/iounmap_allowed()	2022-06-27 12:22:31 +01:00
Kconfig	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
Kconfig.debug	Two followon fixes for the post-5.19 series "Use pageblock_order for cma	2022-05-27 11:40:49 -07:00
khugepaged.c	mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths	2022-11-30 14:49:42 -08:00
kmemleak.c	mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops	2022-10-28 13:37:22 -07:00
ksm.c	ksm: use a folio in replace_page()	2022-10-03 14:02:53 -07:00
list_lru.c	mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe	2022-06-16 19:48:31 -07:00
maccess.c	maccess: Fix writing offset in case of fault in strncpy_from_kernel_nofault()	2022-11-11 11:44:46 -08:00
madvise.c	madvise: use zap_page_range_single for madvise dontneed	2022-11-30 14:49:40 -08:00
Makefile	mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol	2022-10-03 14:03:36 -07:00
mapping_dirty_helpers.c
memblock.c	mm: add pageblock_align() macro	2022-10-03 14:03:04 -07:00
memcontrol.c	memcg: Fix possible use-after-free in memcg_write_event_control()	2022-12-08 10:40:58 -08:00
memfd.c
memory_hotplug.c	mm: add pageblock_aligned() macro	2022-10-03 14:03:04 -07:00
memory-failure.c	hugetlbfs: don't delete error page from pagecache	2022-11-08 15:57:22 -08:00
memory-tiers.c	memory tier, sysfs: rename attribute "nodes" to "nodelist"	2022-10-28 13:37:22 -07:00
memory.c	hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing	2022-11-30 14:49:40 -08:00
mempolicy.c	mm/mempolicy: fix mbind_range() arguments to vma_merge()	2022-10-20 21:27:21 -07:00
mempool.c	mm/mempool: use might_alloc()	2022-06-16 19:48:30 -07:00
memremap.c	mm/memremap.c: map FS_DAX device memory as decrypted	2022-11-08 15:57:23 -08:00
memtest.c
migrate_device.c	mm/migrate_device: return number of migrating pages in args->cpages	2022-11-22 18:50:43 -08:00
migrate.c	mm: migrate: fix return value if all subpages of THPs are migrated successfully	2022-10-28 13:37:22 -07:00
mincore.c	mm: teach core mm about pte markers	2022-05-13 07:20:09 -07:00
mlock.c	mm/mlock: drop dead code in count_mm_mlocked_page_nr()	2022-09-26 19:46:27 -07:00
mm_init.c	mm: multi-gen LRU: groundwork	2022-09-26 19:46:09 -07:00
mm_slot.h	mm: introduce common struct mm_slot	2022-10-03 14:02:43 -07:00
mmap_lock.c
mmap.c	Revert "mm: align larger anonymous mappings on THP boundaries"	2022-12-04 12:51:59 -08:00
mmu_gather.c	mm/khugepaged: fix GUP-fast interaction by sending IPI	2022-11-30 14:49:42 -08:00
mmu_notifier.c	mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()	2022-04-21 20:01:10 -07:00
mmzone.c	mm: multi-gen LRU: groundwork	2022-09-26 19:46:09 -07:00
mprotect.c	mm/uffd: fix warning without PTE_MARKER_UFFD_WP compiled in	2022-10-12 15:56:46 -07:00
mremap.c	mm: add merging after mremap resize	2022-09-26 19:46:28 -07:00
msync.c	mm/msync: use vma_find() instead of vma linked list	2022-09-26 19:46:25 -07:00
nommu.c	mm: remove the vma linked list	2022-09-26 19:46:26 -07:00
oom_kill.c	mm: reduce noise in show_mem for lowmem allocations	2022-09-26 19:46:29 -07:00
page_alloc.c	mm: fix unexpected changes to {failslab|fail_page_alloc}.attr	2022-11-22 18:50:44 -08:00
page_counter.c	mm: page_counter: remove unneeded atomic ops for low/min	2022-09-11 20:26:01 -07:00
page_ext.c	mm/page_exit: fix kernel doc warning in page_ext_put()	2022-11-22 18:50:41 -08:00
page_idle.c	mm: don't be stuck to rmap lock on reclaim path	2022-05-19 14:08:54 -07:00
page_io.c	swap: convert swap_writepage() to use a folio	2022-10-03 14:02:52 -07:00
page_isolation.c	mm/page_isolation: fix clang deadcode warning	2022-10-28 13:37:22 -07:00
page_owner.c	mm: reuse pageblock_start/end_pfn() macro	2022-10-03 14:03:03 -07:00
page_poison.c
page_reporting.c
page_reporting.h
page_table_check.c	mm/page_table_check: fix typos	2022-10-03 14:03:27 -07:00
page_vma_mapped.c	mm/swap: add swp_offset_pfn() to fetch PFN from swap entry	2022-09-26 19:46:05 -07:00
page-writeback.c	mm: export balance_dirty_pages_ratelimited_flags()	2022-09-26 12:28:07 +02:00
pagewalk.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
percpu-internal.h	percpu: improve percpu_alloc_percpu event trace	2022-05-13 07:20:18 -07:00
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c	mm: percpu: use kmemleak_ignore_phys() instead of kmemleak_free()	2022-07-17 17:14:47 -07:00
pgalloc-track.h
pgtable-generic.c	mm: avoid unnecessary flush on change_huge_pmd()	2022-05-13 07:20:05 -07:00
process_vm_access.c
ptdump.c	mm: pagewalk: Fix race between unmap and page walker	2022-09-03 10:13:13 -07:00
readahead.c	mm: add PSI accounting around ->read_folio and ->readahead calls	2022-09-20 08:24:38 -06:00
rmap.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
rodata_test.c	mm/rodata_test: use PAGE_ALIGNED() helper	2022-10-03 14:03:05 -07:00
secretmem.c	mm/secretmem: remove reduntant return value	2022-10-03 14:03:36 -07:00
shmem.c	mm/shmem: ensure proper fallback if page faults	2022-10-28 13:37:23 -07:00
shrinker_debug.c	mm: shrinkers: fix double kfree on shrinker name	2022-07-29 18:07:13 -07:00
shuffle.c	mm/shuffle: convert module_param_call to module_param_cb	2022-10-03 14:03:07 -07:00
shuffle.h
slab_common.c	mm, slab: remove duplicate kernel-doc comment for ksize()	2022-11-07 17:11:27 +01:00
slab.c	Random number generator fixes for Linux 6.1-rc1.	2022-10-16 15:27:07 -07:00
slab.h	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
slob.c	Merge branch 'slab/for-6.1/kmalloc_size_roundup' into slab/for-next	2022-09-29 11:30:55 +02:00
slub.c	treewide: use prandom_u32_max() when possible, part 1	2022-10-11 17:42:55 -06:00
sparse-vmemmap.c	mm: hugetlb_vmemmap: move vmemmap code related to HugeTLB to hugetlb_vmemmap.c	2022-08-08 18:06:42 -07:00
sparse.c	mm: memory_hotplug: enumerate all supported section flags	2022-07-03 18:08:49 -07:00
swap_cgroup.c	mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled	2022-10-03 14:03:36 -07:00
swap_slots.c	mm/swap: convert put_swap_page() to put_swap_folio()	2022-10-03 14:02:46 -07:00
swap_state.c	swap_state: convert free_swap_cache() to use a folio	2022-10-03 14:02:51 -07:00
swap.c	mm: add folio_add_lru_vma()	2022-10-03 14:02:45 -07:00
swap.h	mm: remove lookup_swap_cache()	2022-10-03 14:02:51 -07:00
swapfile.c	swapfile: fix soft lockup in scan_swap_map_slots	2022-11-22 18:50:44 -08:00
truncate.c	mm: add split_folio()	2022-10-03 14:02:45 -07:00
usercopy.c	usercopy: use unsigned long instead of uintptr_t	2022-07-01 17:03:38 -07:00
userfaultfd.c	mm/shmem: use page_mapping() to detect page cache for uffd continue	2022-11-08 15:57:23 -08:00
util.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
vmalloc.c	mm: kmsan: maintain KMSAN metadata for page operations	2022-10-03 14:03:20 -07:00
vmpressure.c
vmscan.c	mm: introduce arch_has_hw_nonleaf_pmd_young()	2022-11-30 14:49:41 -08:00
vmstat.c	- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in	2022-10-10 17:53:04 -07:00
workingset.c	mm: multi-gen LRU: minimal implementation	2022-09-26 19:46:09 -07:00
z3fold.c	mm: Convert all PageMovable users to movable_operations	2022-08-02 12:34:03 -04:00
zbud.c
zpool.c
zsmalloc.c	zsmalloc: zs_destroy_pool: add size_class NULL check	2022-10-20 21:27:21 -07:00
zswap.c	mm/swap: remove the end_write_func argument to __swap_writepage	2022-09-11 20:25:50 -07:00