CVE-2025-39782
What it is
In the Linux kernel, the following vulnerability has been resolved: jbd2: prevent softlockup in jbd2_log_do_checkpoint() Both jbd2_log_do_checkpoint() and jbd2_journal_shrink_checkpoint_list() periodically release j_list_lock after processing a batch of buffers to avoid long hold times on the j_list_lock. However, since both functions contend for j_list_lock, the combined time spent waiting and processing can be significant. jbd2_journal_shrink_checkpoint_list() explicitly calls cond_resched() when need_resched() is true to avoid softlockups during prolonged operations. But jbd2_log_do_checkpoint() only exits its loop when need_resched() is true, relying on potentially sleeping functions like __flush_batch() or wait_on_buffer() to trigger rescheduling. If those functions do not sleep, the kernel may hit a softlockup. watchdog: BUG: soft lockup - CPU#3 stuck for 156s! [kworker/u129:2:373] CPU: 3 PID: 373 Comm: kworker/u129:2 Kdump: loaded Not tainted 6.6.0+ #10 Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.27 06/13/2017 Workqueue: writeback wb_workfn (flush-7:2) pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : native_queued_spin_lock_slowpath+0x358/0x418 lr : jbd2_log_do_checkpoint+0x31c/0x438 [jbd2] Call trace: native_queued_spin_lock_slowpath+0x358/0x418 jbd2_log_do_checkpoint+0x31c/0x438 [jbd2] __jbd2_log_wait_for_space+0xfc/0x2f8 [jbd2] add_transaction_credits+0x3bc/0x418 [jbd2] start_this_handle+0xf8/0x560 [jbd2] jbd2__journal_start+0x118/0x228 [jbd2] __ext4_journal_start_sb+0x110/0x188 [ext4] ext4_do_writepages+0x3dc/0x740 [ext4] ext4_writepages+0xa4/0x190 [ext4] do_writepages+0x94/0x228 __writeback_single_inode+0x48/0x318 writeback_sb_inodes+0x204/0x590 __writeback_inodes_wb+0x54/0xf8 wb_writeback+0x2cc/0x3d8 wb_do_writeback+0x2e0/0x2f8 wb_workfn+0x80/0x2a8 process_one_work+0x178/0x3e8 worker_thread+0x234/0x3b8 kthread+0xf0/0x108 ret_from_fork+0x10/0x20 So explicitly call cond_resched() in jbd2_log_do_checkpoint() to avoid softlockup.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-667
- Record status
- Modified
Affected
- Linux Kernel < 5.4.297
- Linux Kernel < 5.10.241
- Linux Kernel < 5.15.190
- Linux Kernel < 6.1.149
- Linux Kernel < 6.6.103
- Linux Kernel < 6.12.44
- Linux Kernel < 6.16.4
- Linux Kernel 6.17
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2025-39782.md and follow it. Check whether this project is affected by CVE-2025-39782. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/26cb9aad94cb1811d8fae115594cc71fa3d91ab0
- https://git.kernel.org/stable/c/3faac5e1d14c63260fd1bf789d96bde3ab3d9e54
- https://git.kernel.org/stable/c/41f40038de62e8306897cf6840791b268996432a
- https://git.kernel.org/stable/c/429d50cbaff45090d52a1ea850d5de8c14881ee7
- https://git.kernel.org/stable/c/84ff98c1ea19acd3f9389e4bb6061364e943f85e
- https://git.kernel.org/stable/c/9d98cf4632258720f18265a058e62fde120c0151
- https://git.kernel.org/stable/c/f683d611518d30334813eecf9a8c687453e2800e
- https://git.kernel.org/stable/c/f7ee8fd689e6d534f9fd2494b9266f7998082e65
References
- https://git.kernel.org/stable/c/26cb9aad94cb1811d8fae115594cc71fa3d91ab0
- https://git.kernel.org/stable/c/3faac5e1d14c63260fd1bf789d96bde3ab3d9e54
- https://git.kernel.org/stable/c/41f40038de62e8306897cf6840791b268996432a
- https://git.kernel.org/stable/c/429d50cbaff45090d52a1ea850d5de8c14881ee7
- https://git.kernel.org/stable/c/84ff98c1ea19acd3f9389e4bb6061364e943f85e
- https://git.kernel.org/stable/c/9d98cf4632258720f18265a058e62fde120c0151
- https://git.kernel.org/stable/c/f683d611518d30334813eecf9a8c687453e2800e
- https://git.kernel.org/stable/c/f7ee8fd689e6d534f9fd2494b9266f7998082e65
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html