=============================
WARNING: suspicious RCU usage
5.15.174-syzkaller #0 Not tainted
-----------------------------
net/sched/sch_api.c:304 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
9 locks held by rm/5561:
#0: ffff888022dc9d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff888022dc9d28 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x175/0x2d0 mm/util.c:549
#1: ffff888022dc9c90 (&mm->page_table_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline]
#1: ffff888022dc9c90 (&mm->page_table_lock){+.+.}-{2:2}, at: browse_rb mm/mmap.c:355 [inline]
#1: ffff888022dc9c90 (&mm->page_table_lock){+.+.}-{2:2}, at: validate_mm+0x36e/0x990 mm/mmap.c:422
#2: ffffc90000007be0 ((&peer->hb_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline]
#2: ffffc90000007be0 ((&peer->hb_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbe/0x560 kernel/time/timer.c:1441
#3: ffff88814cb2a4a0 (slock-AF_INET6){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline]
#3: ffff88814cb2a4a0 (slock-AF_INET6){+.-.}-{2:2}, at: sctp_generate_heartbeat_event+0x8c/0x450 net/sctp/sm_sideeffect.c:371
#4: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
#5: ffffffff8cb1fd80 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
#6: ffffffff8cb1fd80 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
#7: ffff88806605b108 (&sch->q.lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline]
#7: ffff88806605b108 (&sch->q.lock){+.-.}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3879 [inline]
#7: ffff88806605b108 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0xc1f/0x32b0 net/core/dev.c:4221
#8: ffffffff8cb1fd20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
stack backtrace:
CPU: 0 PID: 5561 Comm: rm Not tainted 5.15.174-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
qdisc_lookup+0xa8/0x630 net/sched/sch_api.c:304
qdisc_tree_reduce_backlog+0x212/0x4f0 net/sched/sch_api.c:800
pfifo_tail_enqueue+0x2ca/0x400 net/sched/sch_fifo.c:51
qdisc_enqueue include/net/sch_generic.h:832 [inline]
tbf_enqueue+0x35d/0x6f0 net/sched/sch_tbf.c:243
dev_qdisc_enqueue+0x47/0x240 net/core/dev.c:3820
__dev_xmit_skb net/core/dev.c:3904 [inline]
__dev_queue_xmit+0xe32/0x32b0 net/core/dev.c:4221
neigh_hh_output include/net/neighbour.h:493 [inline]
neigh_output include/net/neighbour.h:507 [inline]
ip_finish_output2+0xcd7/0x11a0 net/ipv4/ip_output.c:228
dst_output include/net/dst.h:443 [inline]
ip_local_out net/ipv4/ip_output.c:126 [inline]
__ip_queue_xmit+0x12df/0x1d90 net/ipv4/ip_output.c:532
sctp_packet_transmit+0x2565/0x2b70 net/sctp/output.c:652
sctp_outq_flush_transports net/sctp/outqueue.c:1170 [inline]
sctp_outq_flush+0x13c7/0x3d70 net/sctp/outqueue.c:1218
sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
sctp_do_sm+0x55e7/0x5c80 net/sctp/sm_sideeffect.c:1170
sctp_generate_heartbeat_event+0x321/0x450 net/sctp/sm_sideeffect.c:391
call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451
expire_timers kernel/time/timer.c:1496 [inline]
__run_timers+0x67c/0x890 kernel/time/timer.c:1767
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
__do_softirq kernel/softirq.c:592 [inline]
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 ac 90 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900013df580 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200027bebc RCX: ffffffff81638982
RDX: dffffc0000000000 RSI: ffffffff8aab3e20 RDI: ffffffff8af9f000
RBP: ffffc900013df6d0 R08: dffffc0000000000 R09: fffffbfff2131221
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200027beb8
R13: dffffc0000000000 R14: ffffc900013df5e0 R15: 0000000000000246
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:363 [inline]
browse_rb mm/mmap.c:355 [inline]
validate_mm+0x36e/0x990 mm/mmap.c:422
__vma_adjust+0x2cde/0x3150 mm/mmap.c:1020
__split_vma+0x34f/0x420
__do_munmap+0x38e/0x1710 mm/mmap.c:2844
do_munmap mm/mmap.c:2898 [inline]
munmap_vma_range mm/mmap.c:602 [inline]
__mmap_region mm/mmap.c:1745 [inline]
mmap_region+0x9f9/0x1870 mm/mmap.c:2921
do_mmap+0x78d/0xe00 mm/mmap.c:1574
vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551
ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1623
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8ad92c9b74
Code: 63 08 44 89 e8 5b 41 5c 41 5d c3 41 89 ca 41 f7 c1 ff 0f 00 00 74 0c c7 05 f5 46 01 00 16 00 00 00 eb 17 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 dc 46 01 00 48 83 c8 ff c3 0f
RSP: 002b:00007ffe991de5a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ffe991de5e8 RCX: 00007f8ad92c9b74
RDX: 0000000000000005 RSI: 0000000000006000 RDI: 00007f8ad902b000
RBP: 00007ffe991de980 R08: 0000000000000003 R09: 0000000000003000
R10: 0000000000000812 R11: 0000000000000246 R12: 00007f8ad92acac0
R13: 00007ffe991dea08 R14: 0000000000002ee0 R15: 0000000000000000
----------------
Code disassembly (best guess):
0: 2b 00 sub (%rax),%eax
2: 74 08 je 0xc
4: 4c 89 f7 mov %r14,%rdi
7: e8 ac 90 67 00 call 0x6790b8
c: f6 44 24 61 02 testb $0x2,0x61(%rsp)
11: 0f 85 84 01 00 00 jne 0x19b
17: 41 f7 c7 00 02 00 00 test $0x200,%r15d
1e: 74 01 je 0x21
20: fb sti
21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp)
28: e0 45
* 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction
31: 00 00
33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1)
3a: 00 00
3c: 43 rex.XB
3d: c7 .byte 0xc7
3e: 44 rex.R
3f: 25 .byte 0x25