cbcvebase.
CVE-2024-35892
published 2024-05-19

CVE-2024-35892: 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…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.17%
6.7th percentile
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: [] __dump_stack lib/dump_stack.c:88 [inline] [] dump_stack_lvl+0x1b1/0x28f lib/dump_stack.c:106 [] dump_stack+0x15/0x1e lib/dump_stack.c:113 [] lockdep_rcu_suspicious+0x1b9/0x260 kernel/locking/lockdep.c:6592 [] qdisc_lookup+0xac/0x6f0 net/sched/sch_api.c:305 [] qdisc_tree_reduce_backlog+0x243/0x580 net/sched/sch_api.c:811 [] pfifo_tail_enqueue+0x32c/0x4b0 net/sched/sch_fifo.c:51 [] qdisc_enqueue include/net/sch_generic.h:833 [inline] [] nete

Affected

17 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.85-1 (bookworm)linux 6.1.85-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 6.1.34 < 6.1.856.1.85
linuxlinux>= 6.3.8 < 6.46.4
linuxlinux>= 9d9a38b5639fcefacc1e977567fb4b4e4a74d0b3 < b7d1ce2cc7192e8a037faa3f5d3ba72c25976460b7d1ce2cc7192e8a037faa3f5d3ba72c25976460
linuxlinux>= d636fc5dd692c8f4e00ae6e0359c0eceeb5d9bdb < c040b99461a5bfc14c2d0cbb1780fcc3a4706c7ec040b99461a5bfc14c2d0cbb1780fcc3a4706c7e
linuxlinux>= d636fc5dd692c8f4e00ae6e0359c0eceeb5d9bdb < 07696415526bee0607e495017369c7303a4792e107696415526bee0607e495017369c7303a4792e1
linuxlinux>= d636fc5dd692c8f4e00ae6e0359c0eceeb5d9bdb < 7eb322360b0266481e560d1807ee79e0cef5742b7eb322360b0266481e560d1807ee79e0cef5742b
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.85-16.1.85-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.0-38.386.8.0-38.38
linuxlinux_kernel>= 6.1.34 < 6.1.856.1.85
linuxlinux_kernel>= 6.3.8 < 6.6.266.6.26
linuxlinux_kernel>= 6.7 < 6.8.56.8.5

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv6.8MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu4.6MEDIUM
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