Christian Brauner
5d3975e36c
tmpfs: verify {g,u}id mount options correctly ...
[ Upstream commit 0200679fc7953177941e41c2a4241d0b6c2c5de8 ]
A while ago we received the following report:
"The other outstanding issue I noticed comes from the fact that
fsconfig syscalls may occur in a different userns than that which
called fsopen. That means that resolving the uid/gid via
current_user_ns() can save a kuid that isn't mapped in the associated
namespace when the filesystem is finally mounted. This means that it
is possible for an unprivileged user to create files owned by any
group in a tmpfs mount (since we can set the SUID bit on the tmpfs
directory), or a tmpfs that is owned by any user, including the root
group/user."
The contract for {g,u}id mount options and {g,u}id values in general set
from userspace has always been that they are translated according to the
caller's idmapping. In so far, tmpfs has been doing the correct thing.
But since tmpfs is mountable in unprivileged contexts it is also
necessary to verify that the resulting {k,g}uid is representable in the
namespace of the superblock to avoid such bugs as above.
The new mount api's cross-namespace delegation abilities are already
widely used. After having talked to a bunch of userspace this is the
most faithful solution with minimal regression risks. I know of one
users - systemd - that makes use of the new mount api in this way and
they don't set unresolable {g,u}ids. So the regression risk is minimal.
Link: https://lore.kernel.org/lkml/CALxfFW4BXhEwxR0Q5LSkg-8Vb4r2MONKCcUCVioehXQKr35eHg@mail.gmail.com
Fixes: f32356261d
2023-09-23 10:59:40 +02:00
panic: Consolidate open-coded panic_on_warn checks
2023-02-06 07:52:50 +01:00
mm: bdi: initialize bdi_min_ratio when bdi is unregistered
2021-12-14 14:49:00 +01:00
cma: don't quit at first error when activating reserved areas
2020-09-03 11:26:51 +02:00
mm, compaction: fix fast_isolate_around() to stay within boundaries
2023-01-18 11:41:44 +01:00
mm: allow a controlled amount of unfairness in the page lock
2023-08-30 16:27:26 +02:00
v4l2: don't fall back to follow_pfn() if pin_user_pages_fast() fails
2022-12-08 11:23:06 +01:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page
2022-12-19 12:24:15 +01:00
mm/thp: check and bail out if page in deferred queue already
2023-03-11 16:44:05 +01:00
mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb page
2022-12-19 12:24:15 +01:00
mm/thp: fix vma_address() if virtual address below file offset
2021-06-30 08:47:52 -04:00
mm/zsmalloc.c: drop ZSMALLOC_PGTABLE_MAPPING
2020-12-16 10:56:59 +01:00
mm/khugepaged: fix collapse_pte_mapped_thp() to allow anon_vma
2023-01-24 07:18:01 +01:00
Revert "mm: kmemleak: take a full lowmem check in kmemleak_*_phys()"
2022-09-15 12:04:49 +02:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm: list_lru: set shrinker map bit when child nr_items is not zero
2020-12-11 13:23:31 +01:00
mm: fix madivse_pageout mishandling on non-LRU page
2022-10-05 10:37:43 +02:00
Revert "mm: Always release pages to the buddy allocator in memblock_free_late()."
2023-02-22 12:50:39 +01:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
memfd: fix F_SEAL_WRITE after shmem huge page allocated
2022-03-08 19:07:49 +01:00
mm/memory-failure: make sure wait for page writeback in memory_failure
2021-06-23 14:41:23 +02:00
mm: hugetlb: fix missing cache flush in copy_huge_page_from_user()
2022-05-15 19:54:47 +02:00
mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range()
2021-09-22 12:26:43 +02:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm/migrate_device.c: flush TLB while holding PTL
2022-10-05 10:37:43 +02:00
mm: Fix TLB flush for not-first PFNMAP mappings in unmap_region()
2022-09-20 12:28:00 +02:00
mm: fix kthread_use_mm() vs TLB invalidate
2020-09-03 11:26:51 +02:00
mm/khugepaged: fix GUP-fast interaction by sending IPI
2022-12-14 11:30:42 +01:00
arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
2022-05-15 19:54:46 +02:00
mm/mremap: hold the rmap lock in write mode when moving page table entries.
2022-08-25 11:17:20 +02:00
oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup
2022-04-27 13:50:48 +02:00
mm: make wait_on_page_writeback() wait for multiple pending writebacks
2023-06-28 10:18:42 +02:00
mm/page_alloc: fix potential deadlock on zonelist_update_seq seqlock
2023-05-17 11:36:05 +02:00
mm/page_counter.c: fix protection usage propagation
2020-08-21 13:05:27 +02:00
mm: fix unexpected zeroed page mapping with zram swap
2022-05-12 12:23:48 +02:00
mm/memory_hotplug: drain per-cpu pages again during memory offline
2020-09-23 12:40:47 +02:00
mm/page_owner: change split_page_owner to take a count
2020-10-29 09:57:52 +01:00
mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk()
2021-06-30 08:47:55 -04:00
mm: pagewalk: Fix race between unmap and page walker
2022-10-15 07:54:36 +02:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm/thp: fix __split_huge_pmd_locked() on shmem migration entry
2021-06-30 08:47:52 -04:00
mm/rmap: Fix anon_vma->degree ambiguity leading to double-reuse
2022-09-05 10:27:46 +02:00
tmpfs: verify {g,u}id mount options correctly
2023-09-23 10:59:40 +02:00
mm/shuffle: don't move pages between zones and don't read garbage memmaps
2020-09-03 11:26:51 +02:00
mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag
2021-11-26 10:47:21 +01:00
mm: slab: fix kmem_cache_create failed when sysfs node not destroyed
2021-07-25 14:35:14 +02:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm/sparse: add the missing sparse_buffer_fini() in error branch
2021-05-14 09:44:32 +02:00
treewide: Remove uninitialized_var() usage
2023-06-09 10:29:01 +02:00
mm/swap_state: fix a data race in swapin_nr_pages
2020-10-01 13:18:08 +02:00
mm/swap: fix swap_info_struct race between swapoff and get_swap_pages()
2023-04-20 12:07:35 +02:00
mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page()
2021-06-30 08:47:53 -04:00
mm/usercopy: return 1 from hardened_usercopy __setup() handler
2022-04-15 14:18:30 +02:00
mm: userfaultfd: fix missing cache flush in mcopy_atomic_pte() and __mcopy_atomic()
2022-05-15 19:54:47 +02:00
random: move randomize_page() into mm where it belongs
2022-06-22 14:11:17 +02:00
mm/vunmap: add cond_resched() in vunmap_pmd_range
2020-09-03 11:26:52 +02:00
mm,vmscan: fix divide by zero in get_scan_count
2021-09-22 12:26:37 +02:00
arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
2022-05-15 19:54:46 +02:00
mm/z3fold: fix potential memory leak in z3fold_destroy_pool()
2021-07-14 16:53:47 +02:00
zsmalloc: fix races between asynchronous zspage free and page migration
2022-06-06 08:33:50 +02:00
5d3975e36c