kernel: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue()

A flaw was found in the HFSC queueing discipline implementation in the Linux kernel. When a packet is enqueued and the child qdisc's peek function is called before properly updating the HFSC queue's length and backlog counters, a race condition can occur. In some cases, the peek operation may...

DEBIAN-CVE-2025-38350

In the Linux kernel, the following vulnerability has been resolved: net/sched: Always pass notifications when child class becomes empty Certain classful qdiscs may invoke their classes' dequeue handler on an enqueue operation. This may unexpectedly empty the child qdisc and thus make an in-flight...

OESA-2025-1874 kernel security update

The Linux Kernel, the operating system core itself. Security Fixes: In the Linux kernel, the following vulnerability has been resolved: pfifotailenqueue: Drop new packet when sch-limit == 0 Expected behaviour: In case we reach scheduler's limit, pfifotailenqueue will drop a packet in scheduler's...

OESA-2025-1869 kernel security update

The Linux Kernel, the operating system core itself. Security Fixes: In the Linux kernel, the following vulnerability has been resolved: pfifotailenqueue: Drop new packet when sch-limit == 0 Expected behaviour: In case we reach scheduler's limit, pfifotailenqueue will drop a packet in scheduler's...

sch_htb: make htb_qlen_notify() idempotent

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UBUNTU-CVE-2025-38177

In the Linux kernel, the following vulnerability has been resolved: schhfsc: make hfscqlennotify idempotent hfscqlennotify is not idempotent either and not friendly to its callers, like fqcodeldequeue. Let's make it idempotent to ease qdisctreereducebacklog callers' life: 1. updatevf decreases...

SUSE CVE-2025-38107

In the Linux kernel, the following vulnerability has been resolved: netsched: ets: fix a race in etsqdiscchange Gerrard Tai reported a race condition in ETS, 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 roo...

SUSE CVE-2025-38108

In the Linux kernel, the following vulnerability has been resolved: netsched: red: fix a race in redchange Gerrard Tai reported a race condition in RED, 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 | |...

PT-2025-30120

Name of the Vulnerable Software and Affected Versions Linux kernel affected versions not specified Description The Linux kernel contains a flaw in the networking scheduler where certain classful qdiscs may unexpectedly empty a child qdisc, leading to a use-after-free condition. This can occur whe...

UBUNTU-CVE-2025-38083

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 | ...

AZL-63684 CVE-2025-38000 affecting package kernel for versions less than 6.6.96.1-1

In the Linux kernel, the following vulnerability has been resolved: schhfsc: Fix qlen accounting bug when using peek in hfscenqueue When enqueuing the first packet to an HFSC class, hfscenqueue calls the child qdisc's peek operation before incrementing sch-q.qlen and sch-qstats.backlog. If the...

DEBIAN-CVE-2025-38000

In the Linux kernel, the following vulnerability has been resolved: schhfsc: Fix qlen accounting bug when using peek in hfscenqueue When enqueuing the first packet to an HFSC class, hfscenqueue calls the child qdisc's peek operation before incrementing sch-q.qlen and sch-qstats.backlog. If the...

SUSE CVE-2025-37915

In the Linux kernel, the following vulnerability has been resolved: netsched: drr: Fix double list add in class with netem as child qdisc As described in Gerrard's report 1, there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of drr,...

UBUNTU-CVE-2025-37932

In the Linux kernel, the following vulnerability has been resolved: schhtb: make htbqlennotify idempotent htbqlennotify always deactivates the HTB class and in fact could trigger a warning if it is already deactivated. Therefore, it is not idempotent and not friendly to its callers, like...

kernel: net: sched: fix ordering of qlen adjustment

In the Linux kernel, the following vulnerability has been resolved: net: sched: fix ordering of qlen adjustment Changes to sch-q.qlen around qdisctreereducebacklog need to happen before a call to said function because otherwise it may fail to notify parent qdiscs when the child is about to become...

SUSE CVE-2025-37797

In the Linux kernel, the following vulnerability has been resolved: netsched: hfsc: Fix a UAF vulnerability in class handling This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class handling. The issue occurs due to a time-of-check/time-of-use condition in hfscchangeclass when...

netem: Update sch->q.qlen before qdisc_tree_reduce_backlog()

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CVE-2025-37797

In the Linux kernel, the following vulnerability has been resolved: netsched: hfsc: Fix a UAF vulnerability in class handling This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class handling. The issue occurs due to a time-of-check/time-of-use condition in hfscchangeclass when...

AZL-69725 CVE-2025-37798 affecting package kernel for versions less than 5.15.200.1-1

In the Linux kernel, the following vulnerability has been resolved: codel: remove sch-q.qlen check before qdisctreereducebacklog After making all -qlennotify callbacks idempotent, now it is safe to remove the check of qlen!=0 from both fqcodeldequeue and codelqdiscdequeue...

DEBIAN-CVE-2025-37798

In the Linux kernel, the following vulnerability has been resolved: codel: remove sch-q.qlen check before qdisctreereducebacklog After making all -qlennotify callbacks idempotent, now it is safe to remove the check of qlen!=0 from both fqcodeldequeue and codelqdiscdequeue...