CVE-2025-38083: net_sched: prio: fix a race in prio_tune()
In the Linux kernel, the following vulnerability has been resolved:
netsched: prio: fix a race in priotune()
Gerrard Tai reported a race condition in PRIO, whenever SFQ perturb timer fires at the wrong time.
The race is as follows:
CPU 0 CPU 1 [1]: lock root [2]: qdisctreeflushbacklog() [3]: unlock root | | [5]: lock root | [6]: rehash | [7]: qdisctreereducebacklog() | [4]: qdiscput()
This can be abused to underflow a parent's qlen.
Calling qdiscpurgequeue() instead of qdisctreeflushbacklog() should fix the race, because all packets will be purged from the qdisc before releasing the lock.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2025-38083?
CVE-2025-38083 has been classified with a critical severity due to its potential exploitation leading to system instability.
How do I fix CVE-2025-38083?
To fix CVE-2025-38083, update your Linux kernel to the latest version where the vulnerability has been addressed.
What systems are affected by CVE-2025-38083?
CVE-2025-38083 affects various versions of the Linux kernel, particularly those using the PRIO scheduler.
Can CVE-2025-38083 be exploited remotely?
CVE-2025-38083 is not directly exploitable remotely, but it may lead to denial-of-service conditions under specific circumstances.
Who reported CVE-2025-38083?
CVE-2025-38083 was reported by security researcher Gerrard Tai.