Affected: Linux

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

net/sched: ets: Remove drr class from the active list if it changes to strict

Whenever a user issues an ets qdisc change command, transforming a drr class into a strict one, the ets code isn't checking whether that class was in the active list and removing it. This means that, if a user changes a strict class (which was in the active list) back to a drr one, that class will be added twice to the active list [1].

Doing so with the following commands:

tc qdisc add dev lo root handle 1: ets bands 2 strict 1 tc qdisc add dev lo parent 1:2 handle 20: \ tbf rate 8bit burst 100b latency 1s tc filter add dev lo parent 1: basic classid 1:2 ping -c1 -W0.01 -s 56 127.0.0.1 tc qdisc change dev lo root handle 1: ets bands 2 strict 2 tc qdisc change dev lo root handle 1: ets bands 2 strict 1 ping -c1 -W0.01 -s 56 127.0.0.1

Will trigger the following splat with list debug turned on:

[ 59.279014][ T365] ------------[ cut here ]------------ [ 59.279452][ T365] list_add double add: new=ffff88801d60e350, prev=ffff88801d60e350, next=ffff88801d60e2c0. [ 59.280153][ T365] WARNING: CPU: 3 PID: 365 at lib/list_debug.c:35 __list_add_valid_or_report+0x17f/0x220 [ 59.280860][ T365] Modules linked in: [ 59.281165][ T365] CPU: 3 UID: 0 PID: 365 Comm: tc Not tainted 6.18.0-rc7-00105-g7e9f13163c13-dirty #239 PREEMPT(voluntary) [ 59.281977][ T365] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 59.282391][…

Affected: Ubuntu:Pro:20.04:LTS: linux-ibm-5.15, Ubuntu:Pro:20.04:LTS: linux-nvidia-tegra-5.15, Ubuntu:22.04:LTS: linux, Ubuntu:22.04:LTS: linux-aws, Ubuntu:22.04:LTS: linux-gcp, Ubuntu:22.04:LTS: linux-gkeop, Ubuntu:22.04:LTS: linux-ibm, Ubuntu:22.04:LTS: linux-intel-iotg, Ubuntu:22.04:LTS: linux-kvm, Ubuntu:22.04:LTS: linux-lowlatency and 4 more

Qualys discovered that several vulnerabilities existed in the AppArmor Linux kernel Security Module (LSM). An unprivileged local attacker could use these issues to load, replace, and remove arbitrary AppArmor profiles causing denial of service, exposure of sensitive information (kernel memory), local privilege escalation, or possibly escape a container. (LP: #2143853)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - PowerPC architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - ACPI drivers; - ATM drivers; - Drivers core; - Network block device driver; - Bluetooth drivers; - Character device driver; - TPM device driver; - Data acquisition framework and drivers; - Counter interface drivers; - CPU frequency scaling framework; - Intel Stratix 10 firmware drivers; - GPU drivers; - HID subsystem; - Hardware monitoring drivers; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - Input Device (Tablet) drivers; - ISDN/mISDN subsystem; - Macintosh device drivers; - Media drivers; - MOST (Media Oriented Systems Transport) drivers; - MTD block device drivers; - Network drivers; - Mellanox network drivers; - Texas Instruments network drivers; - Ethernet team driver; - MediaTek network drivers; - NVME drivers; - PA-RISC drivers; - PCI subsyste…