{"id":"CVE-2025-71237","summary":"nilfs2: Fix potential block overflow that cause system hang","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: Fix potential block overflow that cause system hang\n\nWhen a user executes the FITRIM command, an underflow can occur when\ncalculating nblocks if end_block is too small. Since nblocks is of\ntype sector_t, which is u64, a negative nblocks value will become a\nvery large positive integer. This ultimately leads to the block layer\nfunction __blkdev_issue_discard() taking an excessively long time to\nprocess the bio chain, and the ns_segctor_sem lock remains held for a\nlong period. This prevents other tasks from acquiring the ns_segctor_sem\nlock, resulting in the hang reported by syzbot in [1].\n\nIf the ending block is too small, typically if it is smaller than 4KiB\nrange, depending on the usage of the segment 0, it may be possible to\nattempt a discard request beyond the device size causing the hang.\n\nExiting successfully and assign the discarded size (0 in this case)\nto range-\u003elen.\n\nAlthough the start and len values in the user input range are too small,\na conservative strategy is adopted here to safely ignore them, which is\nequivalent to a no-op; it will not perform any trimming and will not\nthrow an error.\n\n[1]\ntask:segctord state:D stack:28968 pid:6093 tgid:6093  ppid:2 task_flags:0x200040 flags:0x00080000\nCall Trace:\n rwbase_write_lock+0x3dd/0x750 kernel/locking/rwbase_rt.c:272\n nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357\n nilfs_segctor_thread_construct fs/nilfs2/segment.c:2569 [inline]\n nilfs_segctor_thread+0x6ec/0xe00 fs/nilfs2/segment.c:2684\n\n[ryusuke: corrected part of the commit message about the consequences]","aliases":["ECHO-8ddd-5733-0005"],"modified":"2026-04-21T02:27:01.382630140Z","published":"2026-02-18T14:53:22.436Z","related":["openSUSE-SU-2026:10387-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71237.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2438982f635e6cc2009be68ba2efb2998727d8d4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4aa45f841413cca81882602b4042c53502f34cad"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6457d3ee41a4c15082ac49c5aa7fb933b4a043f3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b8c5ee234bd54f1447c846101fdaef2cf70c2149"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ba18e5f22f26aa4ef78bc3e81f639d1d4f3845e6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/df1e20796c9f3d541cca47fb72e4369ea135642d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ea2278657ad0d62596589fbe2caf995e189e65e7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ed527ef0c264e4bed6c7b2a158ddf516b17f5f66"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71237.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-71237"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"82e11e857be3ffd2a0a952c9db8aa2379e2b9e44"},{"fixed":"6457d3ee41a4c15082ac49c5aa7fb933b4a043f3"},{"fixed":"ba18e5f22f26aa4ef78bc3e81f639d1d4f3845e6"},{"fixed":"2438982f635e6cc2009be68ba2efb2998727d8d4"},{"fixed":"df1e20796c9f3d541cca47fb72e4369ea135642d"},{"fixed":"ea2278657ad0d62596589fbe2caf995e189e65e7"},{"fixed":"4aa45f841413cca81882602b4042c53502f34cad"},{"fixed":"b8c5ee234bd54f1447c846101fdaef2cf70c2149"},{"fixed":"ed527ef0c264e4bed6c7b2a158ddf516b17f5f66"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-71237.json"}}],"schema_version":"1.7.5"}