CVE-2025-71237
Awaiting Analysis
Awaiting Analysis - Queue
BaseFortify
Publication date: 2026-02-18
Last updated on: 2026-03-18
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: Fix potential block overflow that cause system hang
When a user executes the FITRIM command, an underflow can occur when
calculating nblocks if end_block is too small. Since nblocks is of
type sector_t, which is u64, a negative nblocks value will become a
very large positive integer. This ultimately leads to the block layer
function __blkdev_issue_discard() taking an excessively long time to
process the bio chain, and the ns_segctor_sem lock remains held for a
long period. This prevents other tasks from acquiring the ns_segctor_sem
lock, resulting in the hang reported by syzbot in [1].
If the ending block is too small, typically if it is smaller than 4KiB
range, depending on the usage of the segment 0, it may be possible to
attempt a discard request beyond the device size causing the hang.
Exiting successfully and assign the discarded size (0 in this case)
to range->len.
Although the start and len values in the user input range are too small,
a conservative strategy is adopted here to safely ignore them, which is
equivalent to a no-op; it will not perform any trimming and will not
throw an error.
[1]
task:segctord state:D stack:28968 pid:6093 tgid:6093 ppid:2 task_flags:0x200040 flags:0x00080000
Call Trace:
rwbase_write_lock+0x3dd/0x750 kernel/locking/rwbase_rt.c:272
nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2569 [inline]
nilfs_segctor_thread+0x6ec/0xe00 fs/nilfs2/segment.c:2684
[ryusuke: corrected part of the commit message about the consequences]
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | From 6.19 (inc) to 6.19.1 (exc) |
| linux | linux_kernel | From 5.16 (inc) to 6.1.164 (exc) |
| linux | linux_kernel | From 5.11 (inc) to 5.15.201 (exc) |
| linux | linux_kernel | From 6.2 (inc) to 6.6.125 (exc) |
| linux | linux_kernel | From 6.7 (inc) to 6.12.72 (exc) |
| linux | linux_kernel | From 6.13 (inc) to 6.18.11 (exc) |
| linux | linux_kernel | From 3.15 (inc) to 5.10.251 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |