Strix
63.5K

CVE-2026-80866

Unknown

Last modified

CVE-2026-80866 is a vulnerability of currently unknown severity. In the Linux kernel, the following vulnerability has been resolved: tipc: avoid busy looping in tipc_exit_net() Blamed commit introduced a busy-wait loop in tipc_exit_net() to wait for pending UDP bearer cleanup works to complete: while (atomic_read(&tn->wq_count)) cond_resched(); This loop can busy-wait for a long time if cond_resched() is a NOP. This typically happens if the netns exit is executed by a high priority task, or under kernels configured without preemption (CONFIG_PREEMPT_NONE).

Description

In the Linux kernel, the following vulnerability has been resolved: tipc: avoid busy looping in tipc_exit_net() Blamed commit introduced a busy-wait loop in tipc_exit_net() to wait for pending UDP bearer cleanup works to complete: while (atomic_read(&tn->wq_count)) cond_resched(); This loop can busy-wait for a long time if cond_resched() is a NOP. This typically happens if the netns exit is executed by a high priority task, or under kernels configured without preemption (CONFIG_PREEMPT_NONE). In such cases, it wastes CPU cycles and can lead to soft lockups. Fix this by replacing the busy loop with wait_var_event(), allowing the thread to sleep properly until the work queue count reaches zero. Accordingly, update cleanup_bearer() to use atomic_dec_and_test() and wake_up_var() to wake up the waiter when the count drops to zero. This uses the global wait queue hash table, avoiding the need to bloat struct tipc_net with a wait_queue_head_t. The atomic_dec_and_test() provides the necessary memory barrier to ensure the wakeup is not missed.

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
LinuxLinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986, < 522d1d950b9e3b68190a6de7534827c8dccedb73; >= 04c26faa51d1e2fe71cf13c45791f5174c37f986, < c1481c94e74c955e0448ddf46b8615a44d840c1e; d1f76dfadaf8f47ed1753f97dbcbd41c16215ffa; 5195ec5e365a2a9331bfeb585b613a6e94f98dba; b9f5b7ad4ac3af006443f535b1ce7bff1d130d7d; >= 5.4.124, < 5.5; >= 5.10.42, < 5.11; >= 5.12.9, < 5.13
LinuxLinux5.13

References

Timeline

Published
Last Modified
Status
Received

Frequently Asked Questions

What is CVE-2026-80866?
In the Linux kernel, the following vulnerability has been resolved: tipc: avoid busy looping in tipc_exit_net() Blamed commit introduced a busy-wait loop in tipc_exit_net() to wait for pending UDP bearer cleanup works to complete: while (atomic_read(&tn->wq_count)) cond_resched(); This loop can busy-wait for a long time if cond_resched() is a NOP. This typically happens if the netns exit is executed by a high priority task, or under kernels configured without preemption (CONFIG_PREEMPT_NONE). In such cases, it wastes CPU cycles and can lead to soft lockups. Fix this by replacing the busy loop with wait_var_event(), allowing the thread to sleep properly until the work queue count reaches zero. Accordingly, update cleanup_bearer() to use atomic_dec_and_test() and wake_up_var() to wake up the waiter when the count drops to zero. This uses the global wait queue hash table, avoiding the need to bloat struct tipc_net with a wait_queue_head_t. The atomic_dec_and_test() provides the necessary memory barrier to ensure the wakeup is not missed.
How severe is CVE-2026-80866?
Severity scoring for CVE-2026-80866 is pending analysis.
How do I fix CVE-2026-80866?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →

Are you affected by CVE-2026-80866?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST