Upstream information

CVE-2026-74266 at MITRE

Description

In the Linux kernel, the following vulnerability has been resolved:

net/sched: sch_dualpi2: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen

Whenever dualpi2 drops packets during peek, it calls
qdisc_tree_reduce_backlog. An issue arises because it calls
qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops
to zero, but peek returns an skb, the parent's qlen_notify callback will be
executed even though dualpi2 still has 1 packet on the queue and, thus,
mistakenly deactivates the parent's class which leads to a null-ptr-deref:

[ 101.427314][ T599] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] SMP KASAN NOPTI
[ 101.427755][ T599] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]
[ 101.428048][ T599] CPU: 2 UID: 0 PID: 599 Comm: ping Not tainted 7.1.0-rc5-00284-gbce53c430ed7 #102 PREEMPT(full)
[ 101.428400][ T599] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 101.428608][ T599] RIP: 0010:qfq_dequeue (net/sched/sch_qfq.c:1150) sch_qfq
[ 101.428821][ T599] Code: 00 fc ff df 80 3c 02 00 0f 85 46 0c 00 00 4c 8d 73 48 48 89 9d b8 02 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 2d 0c 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b
All code
[ 101.429348][ T599] RSP: 0018:ffff8881110df4f0 EFLAGS: 00010216
[ 101.429541][ T599] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: dffffc0000000000
[ 101.429763][ T599] RDX: 0000000000000009 RSI: 00000024c0000000 RDI: ffff88811436c2b0
[ 101.429985][ T599] RBP: ffff88811436c000 R08: ffff88811436c280 R09: 1ffff11021277523
[ 101.430206][ T599] R10: 1ffff11021277526 R11: 1ffff11021277527 R12: 00000024c0000000
[ 101.430423][ T599] R13: ffff88811436c2b8 R14: 0000000000000048 R15: 0000000020000000
[ 101.430642][ T599] FS: 00007f61813e1c40(0000) GS:ffff8881691ef000(0000) knlGS:0000000000000000
[ 101.430913][ T599] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 101.431100][ T599] CR2: 00005651650850a8 CR3: 000000010ca0b000 CR4: 0000000000750ef0
[ 101.431320][ T599] PKRU: 55555554
[ 101.431433][ T599] Call Trace:
[ 101.431544][ T599] <TASK>
[ 101.431628][ T599] __qdisc_run (net/sched/sch_generic.c:322 net/sched/sch_generic.c:427 net/sched/sch_generic.c:445)
[ 101.431792][ T599] ? dev_qdisc_enqueue (./include/trace/events/qdisc.h:49 (discriminator 22) net/core/dev.c:4176 (discriminator 22))
[ 101.431941][ T599] __dev_queue_xmit (./include/net/pkt_sched.h:120 ./include/net/pkt_sched.h:117 net/core/dev.c:4292 net/core/dev.c:4831)

Fix this by only calling qdisc_tree_reduce_backlog in peek after the
qlen is restored.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail SUSE
Base Score 5.5
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
CVSSv3 Version 3.1

Note from the SUSE Security Team on the kernel-default package

SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details.

SUSE Bugzilla entry: 1276516 [NEW]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-default Not affected
SUSE Linux Enterprise Micro 5.3 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-default Not affected
SUSE Linux Enterprise Micro 5.4 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.5 kernel-default Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP7 kernel-source-rt Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server 16.0 kernel-default Not affected
SUSE Linux Enterprise Server 16.0 kernel-source Not affected
SUSE Linux Enterprise Server 16.1 kernel-default Not affected
SUSE Linux Enterprise Server 16.1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-source Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-default Not affected
SUSE Linux Micro 6.0 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-source-rt Not affected
SUSE Linux Micro 6.1 kernel-default Not affected
SUSE Linux Micro 6.1 kernel-source Not affected
SUSE Linux Micro 6.1 kernel-source-rt Not affected
SUSE Linux Micro 6.2 kernel-default Not affected
SUSE Linux Micro 6.2 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-default Not affected
SUSE Linux Micro Extras 6.0 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-source-rt Not affected
SUSE Linux Micro Extras 6.1 kernel-default Not affected
SUSE Linux Micro Extras 6.1 kernel-source Not affected
SUSE Real Time Module 15 SP7 kernel-source-rt Not affected
openSUSE Leap 16.0 kernel-source Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-source Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Not affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 kernel-source Not affected
SUSE Enterprise Storage 6 kernel-source Not affected
SUSE Enterprise Storage 7 kernel-source Not affected
SUSE Enterprise Storage 7.1 kernel-source Not affected
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-source Not affected
SUSE Linux Enterprise Micro 5.0 kernel-default Not affected
SUSE Linux Enterprise Micro 5.1 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Not affected
SUSE Linux Enterprise Server 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Not affected
SUSE Manager Proxy 4.0 kernel-source Not affected
SUSE Manager Proxy 4.1 kernel-source Not affected
SUSE Manager Proxy 4.2 kernel-source Not affected
SUSE Manager Proxy 4.3 kernel-source Not affected
SUSE Manager Proxy LTS 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server 4.0 kernel-source Not affected
SUSE Manager Retail Branch Server 4.1 kernel-source Not affected
SUSE Manager Retail Branch Server 4.2 kernel-source Not affected
SUSE Manager Retail Branch Server 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-source Not affected
SUSE Manager Server 4.0 kernel-source Not affected
SUSE Manager Server 4.1 kernel-source Not affected
SUSE Manager Server 4.2 kernel-source Not affected
SUSE Manager Server 4.3 kernel-source Not affected
SUSE Manager Server LTS 4.3 kernel-source Not affected
SUSE Real Time Module 15 SP4 kernel-source-rt Not affected
SUSE Real Time Module 15 SP5 kernel-source-rt Not affected
openSUSE Leap 15.3 kernel-source Not affected
openSUSE Leap 15.4 kernel-source Not affected
openSUSE Leap 15.4 kernel-source-rt Not affected
openSUSE Leap 15.5 kernel-source Not affected
openSUSE Leap 15.5 kernel-source-rt Not affected
openSUSE Leap 15.6 kernel-source Not affected


SUSE Timeline for this CVE

CVE page created: Tue Aug 25 15:54:50 2026
CVE page last modified: Tue Sep 1 12:04:49 2026