{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-35892",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fix lockdep splat in qdisc_tree_reduce_backlog()\n\nqdisc_tree_reduce_backlog() is called with the qdisc lock held,\nnot RTNL.\n\nWe must use qdisc_lookup_rcu() instead of qdisc_lookup()\n\nsyzbot reported:\n\nWARNING: suspicious RCU usage\n6.1.74-syzkaller #0 Not tainted\n-----------------------------\nnet/sched/sch_api.c:305 suspicious rcu_dereference_protected() usage!\n\nother info that might help us debug this:\n\nrcu_scheduler_active = 2, debug_locks = 1\n3 locks held by udevd/1142:\n  #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]\n  #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]\n  #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: net_tx_action+0x64a/0x970 net/core/dev.c:5282\n  #1: ffff888171861108 (&sch->q.lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]\n  #1: ffff888171861108 (&sch->q.lock){+.-.}-{2:2}, at: net_tx_action+0x754/0x970 net/core/dev.c:5297\n  #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]\n  #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]\n  #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: qdisc_tree_reduce_backlog+0x84/0x580 net/sched/sch_api.c:792\n\nstack backtrace:\nCPU: 1 PID: 1142 Comm: udevd Not tainted 6.1.74-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024\nCall Trace:\n <TASK>\n  [<ffffffff85b85f14>] __dump_stack lib/dump_stack.c:88 [inline]\n  [<ffffffff85b85f14>] dump_stack_lvl+0x1b1/0x28f lib/dump_stack.c:106\n  [<ffffffff85b86007>] dump_stack+0x15/0x1e lib/dump_stack.c:113\n  [<ffffffff81802299>] lockdep_rcu_suspicious+0x1b9/0x260 kernel/locking/lockdep.c:6592\n  [<ffffffff84f0054c>] qdisc_lookup+0xac/0x6f0 net/sched/sch_api.c:305\n  [<ffffffff84f037c3>] qdisc_tree_reduce_backlog+0x243/0x580 net/sched/sch_api.c:811\n  [<ffffffff84f5b78c>] pfifo_tail_enqueue+0x32c/0x4b0 net/sched/sch_fifo.c:51\n  [<ffffffff84fbcf63>] qdisc_enqueue include/net/sch_generic.h:833 [inline]\n  [<ffffffff84fbcf63>] netem_dequeue+0xeb3/0x15d0 net/sched/sch_netem.c:723\n  [<ffffffff84eecab9>] dequeue_skb net/sched/sch_generic.c:292 [inline]\n  [<ffffffff84eecab9>] qdisc_restart net/sched/sch_generic.c:397 [inline]\n  [<ffffffff84eecab9>] __qdisc_run+0x249/0x1e60 net/sched/sch_generic.c:415\n  [<ffffffff84d7aa96>] qdisc_run+0xd6/0x260 include/net/pkt_sched.h:125\n  [<ffffffff84d85d29>] net_tx_action+0x7c9/0x970 net/core/dev.c:5313\n  [<ffffffff85e002bd>] __do_softirq+0x2bd/0x9bd kernel/softirq.c:616\n  [<ffffffff81568bca>] invoke_softirq kernel/softirq.c:447 [inline]\n  [<ffffffff81568bca>] __irq_exit_rcu+0xca/0x230 kernel/softirq.c:700\n  [<ffffffff81568ae9>] irq_exit_rcu+0x9/0x20 kernel/softirq.c:712\n  [<ffffffff85b89f52>] sysvec_apic_timer_interrupt+0x42/0x90 arch/x86/kernel/apic/apic.c:1107\n  [<ffffffff85c00ccb>] asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:656"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "9d9a38b5639f",
                                            "version_value": "b7d1ce2cc719"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "d636fc5dd692",
                                            "version_value": "c040b99461a5"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.4",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.4",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.1.85",
                                                        "lessThanOrEqual": "6.1.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.6.26",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.8.5",
                                                        "lessThanOrEqual": "6.8.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/b7d1ce2cc7192e8a037faa3f5d3ba72c25976460",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/b7d1ce2cc7192e8a037faa3f5d3ba72c25976460"
            },
            {
                "url": "https://git.kernel.org/stable/c/c040b99461a5bfc14c2d0cbb1780fcc3a4706c7e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/c040b99461a5bfc14c2d0cbb1780fcc3a4706c7e"
            },
            {
                "url": "https://git.kernel.org/stable/c/07696415526bee0607e495017369c7303a4792e1",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/07696415526bee0607e495017369c7303a4792e1"
            },
            {
                "url": "https://git.kernel.org/stable/c/7eb322360b0266481e560d1807ee79e0cef5742b",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/7eb322360b0266481e560d1807ee79e0cef5742b"
            }
        ]
    },
    "generator": {
        "engine": "bippy-a5840b7849dd"
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}