CVSS 3.1
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Атакува се локално, без особени условия, с обикновен потребителски вход и без действие от потребителя.
Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: xfs: fix exchange-range-to-eof file size exchange Norbert Szetei posted a patch containing an incomplete description of a bug in XFS_IOC_EXCHANGE_RANGE's TO_EOF flag. The bug tricks exchange-range into modifying a file so that it has shared blocks starting beyond EOF, which is never allowed because files never have written data beyond EOF, and you can only share written data blocks. This is key to all the incorrect behavior that follows. Eventually I got from Norbert a description of what's going wrong: > Fair. Here it is with physical block numbers, 4k blocks. peer is the file > that gets rewritten and file1 is the one that ends up with the flag > cleared. > > Start, nothing shared: > > peer size 4096 -> [100] > file1 size 12288 -> [200] [201] [202] > donor1 size 4096 -> [300] > donor2 size 4096 -> [400] > > 1. FICLONERANGE peer's block into file1's middle slot: > > peer size 4096 -> [100] > file1 size 12288 -> [200] [100] [202] reflink flag set > ^^^^^ both files own block 100 > > 2. XFS_IOC_EXCHANGE_RANGE file1 against donor1, file1_offset 0, > file2_offset 8192, length 0, TO_EOF. One block is exchanged, and the sizes > are exchanged with it: > > file1 size 4096 -> [200] [100] [300] reflink flag set > ^^^^^^^^^^^ still owned, now past the size > donor1 size 12288 -> [202] > > file1 says it is one block long while it still owns three. Nothing was > unmapped. file2_offset is block 2, so this exchange cannot clear a flag. > > 3. XFS_IOC_EXCHANGE_RANGE file1 against donor2, both offsets 0, length 4096. > By i_disk_size this is two one-block files exchanging everything, so > xmi_can_exchange_reflink_flags() agrees and the flag is cleared: > > file1 size 4096 -> [400] [100] [300] reflink flag CLEARED > donor2 size 4096 -> [200] > > Block 100 is still shared with peer. > > 4. pwrite(file1, 4096, 4096), which is file1's second slot, b
Засегнати продукти
- Linux Linux: 966ceafc7a437105ecfe1cadb3747b2965a260ca преди b361d32b884f8ddcb9bad5d99b69eece648f8e43; 966ceafc7a437105ecfe1cadb3747b2965a260ca преди cf32eb20dfacfd2e92ce86ba1fece9ae5f98a7d8; 966ceafc7a437105ecfe1cadb3747b2965a260ca преди 952b5c99a840c2bff1f6645fd5e06e1db6ec2623; 966ceafc7a437105ecfe1cadb3747b2965a260ca преди 7dfb218c829c1acb626e0fe92c5fddb9a26a03e9
- Linux Linux: 6.10; преди 6.10; 6.12.114 до 6.12.*; 6.18.57 до 6.18.*; 7.2.11 до 7.2.*; от 7.3 нататък
История
- 23 октомври 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-98974
- https://nvd.nist.gov/vuln/detail/CVE-2026-98974
- https://git.kernel.org/stable/c/b361d32b884f8ddcb9bad5d99b69eece648f8e43
- https://git.kernel.org/stable/c/cf32eb20dfacfd2e92ce86ba1fece9ae5f98a7d8
- https://git.kernel.org/stable/c/952b5c99a840c2bff1f6645fd5e06e1db6ec2623
- https://git.kernel.org/stable/c/7dfb218c829c1acb626e0fe92c5fddb9a26a03e9