CVE-2025-71194: Linux kernel · Race Condition
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in e563f59395981fcd69d130761290929806e728d6 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:18 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-06-16.
- Patch
- Available – fixed in e563f59395981fcd69d130761290929806e728d6, dc84036c173cff6a432d9ab926298850b1d2a659, d7b04b40ac8e6d814e35202a0e1568809b818295 +4
Exploitation evidence
Disclosed: evidence found.
CVE published 4 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix deadlock in wait_current_trans() due to ignored transaction type When wait_current_trans() is called during start_transaction(), it currently waits for a blocked transaction without considering whether the given transaction type actually needs to wait for that particular transaction state. The btrfs_blocked_trans_types[] array already defines which transaction types should wait for which transaction states, but this check was missing in wait_current_trans(). This can lead to a deadlock scenario involving two transactions and pending ordered extents: 1. Transaction A is in TRANS_STATE_COMMIT_DOING state 2. A worker processing an ordered extent calls start_transaction() with TRANS_JOIN 3. join_transaction() returns -EBUSY because Transaction A is in TRANS_STATE_COMMIT_DOING 4. Transaction A moves to TRANS_STATE_UNBLOCKED and completes 5. A new Transaction B is created (TRANS_STATE_RUNNING) 6. The ordered extent from step 2 is added to Transaction B's pending ordered extents 7. Transaction B immediately starts commit by another task and enters TRANS_STATE_COMMIT_START 8. The worker finally reaches wait_current_trans(), sees Transaction B in TRANS_STATE_COMMIT_START (a blocked state), and waits unconditionally 9. However, TRANS_JOIN should NOT wait for TRANS_STATE_COMMIT_START according to btrfs_blocked_trans_types[] 10. Transaction B is waiting for pending ordered extents to complete 11. Deadlock: Transaction B waits for ordered extent, ordered extent waits for Transaction B This can be illustrated by the following call stacks: CPU0 CPU1 btrfs_finish_ordered_io() start_transaction(TRANS_JOIN) join_transaction() # -EBUSY (Transaction A is # TRANS_STATE_COMMIT_DOING) # Transaction A completes # Transaction B created # ordered extent added to # Transaction B's pending list btrfs_commit_transaction() # Transaction B enters # TRANS_STATE_COMMIT_START # waiting for pending ordered # extents wait_current_trans() # waits for Transaction B # (should not wait!) Task bstore_kv_sync in btrfs_commit_transaction waiting for ordered extents: __schedule+0x2e7/0x8a0 schedule+0x64/0xe0 btrfs_commit_transaction+0xbf7/0xda0 [btrfs] btrfs_sync_file+0x342/0x4d0 [btrfs] __x64_sys_fdatasync+0x4b/0x80 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Task kworker in wait_current_trans waiting for transaction commit: Workqueue: btrfs-syno_nocow btrfs_work_helper [btrfs] __schedule+0x2e7/0x8a0 schedule+0x64/0xe0 wait_current_trans+0xb0/0x110 [btrfs] start_transaction+0x346/0x5b0 [btrfs] btrfs_finish_ordered_io.isra.0+0x49b/0x9c0 [btrfs] btrfs_work_helper+0xe8/0x350 [btrfs] process_one_work+0x1d3/0x3c0 worker_thread+0x4d/0x3e0 kthread+0x12d/0x150 ret_from_fork+0x1f/0x30 Fix this by passing the transaction type to wait_current_trans() and checking btrfs_blocked_trans_types[cur_trans->state] against the given type before deciding to wait. This ensures that transaction types which are allowed to join during certain blocked states will not unnecessarily wait and cause deadlocks.
References
- git.kernel.org/stable/c/e563f59395981fcd69d130761290929806e728d6 (opens in a new tab)
- git.kernel.org/stable/c/dc84036c173cff6a432d9ab926298850b1d2a659 (opens in a new tab)
- git.kernel.org/stable/c/d7b04b40ac8e6d814e35202a0e1568809b818295 (opens in a new tab)
- git.kernel.org/stable/c/99da896614d17e8a84aeb2b2d464ac046cc8633d (opens in a new tab)
- git.kernel.org/stable/c/8b0bb145d3bc264360f525c9717653be3522e528 (opens in a new tab)
- git.kernel.org/stable/c/9ac63333d600732a56b35ee1fa46836da671eb50 (opens in a new tab)
- git.kernel.org/stable/c/5037b342825df7094a4906d1e2a9674baab50cb2 (opens in a new tab)