CVE-2024-27022: fork: defer linking file vma until vma is fully initialized

Description

In the Linux kernel, the following vulnerability has been resolved: fork: defer linking file vma until vma is fully initialized Thorvald reported a WARNING [1]. And the root cause is below race: CPU 1 CPU 2 fork hugetlbfs_fallocate dup_mmap hugetlbfs_punch_hole i_mmap_lock_write(mapping); vma_interval_tree_insert_after -- Child vma is visible through i_mmap tree. i_mmap_unlock_write(mapping); hugetlb_dup_vma_private -- Clear vma_lock outside i_mmap_rwsem! i_mmap_lock_write(mapping); hugetlb_vmdelete_list vma_interval_tree_foreach hugetlb_vma_trylock_write -- Vma_lock is cleared. tmp->vm_ops->open -- Alloc new vma_lock outside i_mmap_rwsem! hugetlb_vma_unlock_write -- Vma_lock is assigned!!! i_mmap_unlock_write(mapping); hugetlb_dup_vma_private() and hugetlb_vm_op_open() are called outside i_mmap_rwsem lock while vma lock can be used in the same time. Fix this by deferring linking file vma until vma is fully initialized. Those vmas should be initialized first before they can be used.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

8d9bfb2608145cf3e408428c224099e1585471af to < 087de0e15e6830ed630c793fa4bebd62e8348da1affected
8d9bfb2608145cf3e408428c224099e1585471af to < 2e5cbab8ccbfc7d4a3d8a21d3c2a1f2c1aa29b5baffected
8d9bfb2608145cf3e408428c224099e1585471af to < abdb88dd272bbeb93efe01d8e0b7b17e24af3a34affected
8d9bfb2608145cf3e408428c224099e1585471af to < 35e351780fa9d8240dd6f7e4f245f9ea37e96c19affected

Linux Linux

Default version status: affected

6.1affected
0 to < 6.1unaffected
6.1.191 to ≤ 6.1.*unaffected
6.6.134 to ≤ 6.6.*unaffected
6.8.8 to ≤ 6.8.*unaffected
6.9 to ≤ *unaffected

CVE-2024-27022

fork: defer linking file vma until vma is fully initialized

Description

Affected products

Linux Linux

Linux Linux

References