net/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-72390
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-15 06:22:12 UTC
Updated2026-08-17 06:19:05 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: net/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF The teql master->slaves singly linked list is not protected against multiple writes. It can be mod'ed concurently from teql_master_xmit(), teql_dequeue(), teql_init() and teql_destroy() without holding any list lock or RCU protection. [email protected] has demonstrated that the qdisc is freed after an RCU grace period, but teql_master_xmit() running on another CPU can still hold a stale pointer into the list, resulting in a slab-use-after-free: BUG: KASAN: slab-use-after-free in teql_master_xmit+0xf0f/0x16b0 Read of size 8 at addr ffff888013fb0440 by task poc/332 Freed 512-byte region [ffff888013fb0400, ffff888013fb0600) (kmalloc-512) The fix? Add a per-master slaves_lock spinlock that serializes all mutations of master->slaves and the NEXT_SLAVE() links in teql_destroy() and teql_qdisc_init(). teql_master_xmit() also takes the same slaves_lock around those updates. Annotate master->slaves and the per-slave ->next pointer with __rcu and use the appropriate RCU accessors everywhere they are touched: rcu_assign_pointer() on the writer side (under slaves_lock), rcu_dereference_protected() for the writer-side loads (also under slaves_lock), rcu_dereference_bh() for the loads in teql_master_xmit() and rtnl_dereference() for the loads in teql_master_open()/teql_master_mtu(), which run under RTNL. Pair this with rcu_read_lock_bh()/rcu_read_unlock_bh() around the list traversal in teql_master_xmit(), so that readers either observe a fully linked list or are deferred until the in-flight mutation completes. The two early-return paths in teql_master_xmit() are updated to release the RCU-bh read-side critical section before returning, since leaving it held would disable BH on that CPU for good.

Risk And Classification

Primary CVSS: v3.1 7.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.001620000 probability, percentile 0.059360000 (date 2026-08-17)

VersionSourceTypeScoreSeverityVector
3.1416baaa9-dc9f-4396-8d5f-8c081fb06d67Secondary7.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
3.1CNADECLARED7.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 03c67781254c574ae7fa75e881239a78473bdf42 git Not specified
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 735567bde7401f82b064f9f107b52ee1bf84ed8c git Not specified
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 11402e6e18e96df615cbcc58157818dd604b23ff git Not specified
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 9b7d05cbaa60108642402100efa6aa288dd33023 git Not specified
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 b26aa9d993537a4c3167d8ceead3b7c69c3a0aac git Not specified
CNA Linux Linux affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 e5b811fe793166aecc59b085c1b7c31262ef2316 git Not specified
CNA Linux Linux affected 2.6.12 Not specified
CNA Linux Linux unaffected 2.6.12 semver Not specified
CNA Linux Linux unaffected 6.1.178 6.1.* semver Not specified
CNA Linux Linux unaffected 6.6.145 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.97 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.40 6.18.* semver Not specified
CNA Linux Linux unaffected 7.1.5 7.1.* semver Not specified
CNA Linux Linux unaffected 7.2 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/03c67781254c574ae7fa75e881239a78473bdf42 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/9b7d05cbaa60108642402100efa6aa288dd33023 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/b26aa9d993537a4c3167d8ceead3b7c69c3a0aac 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/735567bde7401f82b064f9f107b52ee1bf84ed8c 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/11402e6e18e96df615cbcc58157818dd604b23ff 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/e5b811fe793166aecc59b085c1b7c31262ef2316 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report