Security update for the Linux Kernel RT (Live Patch 1 for SLE 15 SP7) SUSE Patch security@suse.de SUSE Security Team SUSE-SU-2025:03104-1 Final 1 1 2025-09-08T21:13:26Z current 2025-09-08T21:13:26Z 2025-09-08T21:13:26Z cve-database/bin/generate-cvrf.pl 2017-02-24T01:00:00Z Security update for the Linux Kernel RT (Live Patch 1 for SLE 15 SP7) This update for the Linux Kernel 6.4.0-150700_7_3 fixes several issues. The following security issues were fixed: - CVE-2025-38087: net/sched: fix use-after-free in taprio_dev_notifier (bsc#1245504). - CVE-2025-38001: net_sched: hfsc: Address reentrant enqueue adding class to eltree twice (bsc#1244235). - CVE-2025-38000: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() (bsc#1245775). - CVE-2025-38212: ipc: fix to protect IPCS lookups using RCU (bsc#1246030). The CVRF data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0). SUSE-2025-3104,SUSE-SLE-Module-Live-Patching-15-SP6-2025-3104,SUSE-SLE-Module-Live-Patching-15-SP7-2025-3107 Copyright SUSE LLC under the Creative Commons License 4.0 with Attribution (CC-BY-4.0) https://www.suse.com/support/update/announcement/2025/suse-su-202503104-1/ Link for SUSE-SU-2025:03104-1 https://lists.suse.com/pipermail/sle-updates/2025-September/041541.html E-Mail link for SUSE-SU-2025:03104-1 https://www.suse.com/support/security/rating/ SUSE Security Ratings https://bugzilla.suse.com/1244235 SUSE Bug 1244235 https://bugzilla.suse.com/1245505 SUSE Bug 1245505 https://bugzilla.suse.com/1245775 SUSE Bug 1245775 https://bugzilla.suse.com/1246030 SUSE Bug 1246030 https://bugzilla.suse.com/1248108 SUSE Bug 1248108 https://www.suse.com/security/cve/CVE-2025-38000/ SUSE CVE CVE-2025-38000 page https://www.suse.com/security/cve/CVE-2025-38001/ SUSE CVE CVE-2025-38001 page https://www.suse.com/security/cve/CVE-2025-38087/ SUSE CVE CVE-2025-38087 page https://www.suse.com/security/cve/CVE-2025-38212/ SUSE CVE CVE-2025-38212 page SUSE Linux Enterprise Live Patching 15 SP6 SUSE Linux Enterprise Live Patching 15 SP7 kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 as a component of SUSE Linux Enterprise Live Patching 15 SP6 kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 as a component of SUSE Linux Enterprise Live Patching 15 SP7 In the Linux kernel, the following vulnerability has been resolved: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the child qdisc's peek() operation before incrementing sch->q.qlen and sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may trigger an immediate dequeue and potential packet drop. In such cases, qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog have not yet been updated, leading to inconsistent queue accounting. This can leave an empty HFSC class in the active list, causing further consequences like use-after-free. This patch fixes the bug by moving the increment of sch->q.qlen and sch->qstats.backlog before the call to the child qdisc's peek() operation. This ensures that queue length and backlog are always accurate when packet drops or dequeues are triggered during the peek. CVE-2025-38000 SUSE Linux Enterprise Live Patching 15 SP6:kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 SUSE Linux Enterprise Live Patching 15 SP7:kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2025/suse-su-202503104-1/ https://www.suse.com/security/cve/CVE-2025-38000.html CVE-2025-38000 https://bugzilla.suse.com/1244277 SUSE Bug 1244277 https://bugzilla.suse.com/1245775 SUSE Bug 1245775 In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Address reentrant enqueue adding class to eltree twice Savino says: "We are writing to report that this recent patch (141d34391abbb315d68556b7c67ad97885407547) [1] can be bypassed, and a UAF can still occur when HFSC is utilized with NETEM. The patch only checks the cl->cl_nactive field to determine whether it is the first insertion or not [2], but this field is only incremented by init_vf [3]. By using HFSC_RSC (which uses init_ed) [4], it is possible to bypass the check and insert the class twice in the eltree. Under normal conditions, this would lead to an infinite loop in hfsc_dequeue for the reasons we already explained in this report [5]. However, if TBF is added as root qdisc and it is configured with a very low rate, it can be utilized to prevent packets from being dequeued. This behavior can be exploited to perform subsequent insertions in the HFSC eltree and cause a UAF." To fix both the UAF and the infinite loop, with netem as an hfsc child, check explicitly in hfsc_enqueue whether the class is already in the eltree whenever the HFSC_RSC flag is set. [1] https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=141d34391abbb315d68556b7c67ad97885407547 [2] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L1572 [3] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L677 [4] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L1574 [5] https://lore.kernel.org/netdev/8DuRWwfqjoRDLDmBMlIfbrsZg9Gx50DHJc1ilxsEBNe2D6NMoigR_eIRIG0LOjMc3r10nUUZtArXx4oZBIdUfZQrwjcQhdinnMis_0G7VEk=@willsroot.io/T/#u CVE-2025-38001 SUSE Linux Enterprise Live Patching 15 SP6:kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 SUSE Linux Enterprise Live Patching 15 SP7:kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2025/suse-su-202503104-1/ https://www.suse.com/security/cve/CVE-2025-38001.html CVE-2025-38001 https://bugzilla.suse.com/1244234 SUSE Bug 1244234 https://bugzilla.suse.com/1244235 SUSE Bug 1244235 In the Linux kernel, the following vulnerability has been resolved: net/sched: fix use-after-free in taprio_dev_notifier Since taprio's taprio_dev_notifier() isn't protected by an RCU read-side critical section, a race with advance_sched() can lead to a use-after-free. Adding rcu_read_lock() inside taprio_dev_notifier() prevents this. CVE-2025-38087 SUSE Linux Enterprise Live Patching 15 SP6:kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 SUSE Linux Enterprise Live Patching 15 SP7:kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2025/suse-su-202503104-1/ https://www.suse.com/security/cve/CVE-2025-38087.html CVE-2025-38087 https://bugzilla.suse.com/1245504 SUSE Bug 1245504 https://bugzilla.suse.com/1245505 SUSE Bug 1245505 In the Linux kernel, the following vulnerability has been resolved: ipc: fix to protect IPCS lookups using RCU syzbot reported that it discovered a use-after-free vulnerability, [0] [0]: https://lore.kernel.org/all/67af13f8.050a0220.21dd3.0038.GAE@google.com/ idr_for_each() is protected by rwsem, but this is not enough. If it is not protected by RCU read-critical region, when idr_for_each() calls radix_tree_node_free() through call_rcu() to free the radix_tree_node structure, the node will be freed immediately, and when reading the next node in radix_tree_for_each_slot(), the already freed memory may be read. Therefore, we need to add code to make sure that idr_for_each() is protected within the RCU read-critical region when we call it in shm_destroy_orphaned(). CVE-2025-38212 SUSE Linux Enterprise Live Patching 15 SP6:kernel-livepatch-6_4_0-150600_10_39-rt-4-150600.2.1 SUSE Linux Enterprise Live Patching 15 SP7:kernel-livepatch-6_4_0-150700_7_3-rt-3-150700.2.1 important To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch". https://www.suse.com/support/update/announcement/2025/suse-su-202503104-1/ https://www.suse.com/security/cve/CVE-2025-38212.html CVE-2025-38212 https://bugzilla.suse.com/1246029 SUSE Bug 1246029 https://bugzilla.suse.com/1246030 SUSE Bug 1246030