In the Linux kernel, the following vulnerability has been resolved:
netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu()
syzbot reported that nf_reinject() could be called without rcu_read_lock() :
WARNING: suspicious RCU usage
6.9.0-rc7-syzkaller-02060-g5c1672705a1a #0 Not tainted
net/netfilter/nfnetlink_queue.c:263 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor.4/13427:
#0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2190 [inline]
#0: ffffffff8e334f60 (rcu_callback){....}-{0:0}, at: rcu_core+0xa86/0x1830 kernel/rcu/tree.c:2471
#1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: nfqnl_flush net/netfilter/nfnetlink_queue.c:405 [inline]
#1: ffff88801ca92958 (&inst->lock){+.-.}-{2:2}, at: instance_destroy_rcu+0x30/0x220 net/netfilter/nfnetlink_queue.c:172
stack backtrace:
CPU: 0 PID: 13427 Comm: syz-executor.4 Not tainted 6.9.0-rc7-syzkaller-02060-g5c1672705a1a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
lockdep_rcu_suspicious+...
CVE ID: CVE-2024-36286
Vendor: Linux
Product: Linux
EPSS Score: 0.04% (probability of being exploited)
EPSS Percentile: 5.08% (scored less or equal to compared to others)
EPSS Date: 2025-02-04 (when was this score calculated)