ghsa-gv5w-824r-r7xx
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
net/sched: fix lockdep splat in qdisc_tree_reduce_backlog()
qdisc_tree_reduce_backlog() is called with the qdisc lock held, not RTNL.
We must use qdisc_lookup_rcu() instead of qdisc_lookup()
syzbot reported:
WARNING: suspicious RCU usage 6.1.74-syzkaller #0 Not tainted
net/sched/sch_api.c:305 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1 3 locks held by udevd/1142: #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline] #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: net_tx_action+0x64a/0x970 net/core/dev.c:5282 #1: ffff888171861108 (&sch->q.lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline] #1: ffff888171861108 (&sch->q.lock){+.-.}-{2:2}, at: net_tx_action+0x754/0x970 net/core/dev.c:5297 #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline] #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #2: ffffffff87c729a0 (rcu_read_lock){....}-{1:2}, at: qdisc_tree_reduce_backlog+0x84/0x580 net/sched/sch_api.c:792
stack backtrace:
CPU: 1 PID: 1142 Comm: udevd Not tainted 6.1.74-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
{
"affected": [],
"aliases": [
"CVE-2024-35892"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-19T09:15:10Z",
"severity": null
},
"details": "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 (\u0026sch-\u003eq.lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:350 [inline]\n #1: ffff888171861108 (\u0026sch-\u003eq.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 \u003cTASK\u003e\n [\u003cffffffff85b85f14\u003e] __dump_stack lib/dump_stack.c:88 [inline]\n [\u003cffffffff85b85f14\u003e] dump_stack_lvl+0x1b1/0x28f lib/dump_stack.c:106\n [\u003cffffffff85b86007\u003e] dump_stack+0x15/0x1e lib/dump_stack.c:113\n [\u003cffffffff81802299\u003e] lockdep_rcu_suspicious+0x1b9/0x260 kernel/locking/lockdep.c:6592\n [\u003cffffffff84f0054c\u003e] qdisc_lookup+0xac/0x6f0 net/sched/sch_api.c:305\n [\u003cffffffff84f037c3\u003e] qdisc_tree_reduce_backlog+0x243/0x580 net/sched/sch_api.c:811\n [\u003cffffffff84f5b78c\u003e] pfifo_tail_enqueue+0x32c/0x4b0 net/sched/sch_fifo.c:51\n [\u003cffffffff84fbcf63\u003e] qdisc_enqueue include/net/sch_generic.h:833 [inline]\n [\u003cffffffff84fbcf63\u003e] netem_dequeue+0xeb3/0x15d0 net/sched/sch_netem.c:723\n [\u003cffffffff84eecab9\u003e] dequeue_skb net/sched/sch_generic.c:292 [inline]\n [\u003cffffffff84eecab9\u003e] qdisc_restart net/sched/sch_generic.c:397 [inline]\n [\u003cffffffff84eecab9\u003e] __qdisc_run+0x249/0x1e60 net/sched/sch_generic.c:415\n [\u003cffffffff84d7aa96\u003e] qdisc_run+0xd6/0x260 include/net/pkt_sched.h:125\n [\u003cffffffff84d85d29\u003e] net_tx_action+0x7c9/0x970 net/core/dev.c:5313\n [\u003cffffffff85e002bd\u003e] __do_softirq+0x2bd/0x9bd kernel/softirq.c:616\n [\u003cffffffff81568bca\u003e] invoke_softirq kernel/softirq.c:447 [inline]\n [\u003cffffffff81568bca\u003e] __irq_exit_rcu+0xca/0x230 kernel/softirq.c:700\n [\u003cffffffff81568ae9\u003e] irq_exit_rcu+0x9/0x20 kernel/softirq.c:712\n [\u003cffffffff85b89f52\u003e] sysvec_apic_timer_interrupt+0x42/0x90 arch/x86/kernel/apic/apic.c:1107\n [\u003cffffffff85c00ccb\u003e] asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:656",
"id": "GHSA-gv5w-824r-r7xx",
"modified": "2024-05-19T09:34:47Z",
"published": "2024-05-19T09:34:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-35892"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/07696415526bee0607e495017369c7303a4792e1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7eb322360b0266481e560d1807ee79e0cef5742b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b7d1ce2cc7192e8a037faa3f5d3ba72c25976460"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c040b99461a5bfc14c2d0cbb1780fcc3a4706c7e"
}
],
"schema_version": "1.4.0",
"severity": []
}