=============================
WARNING: suspicious RCU usage
6.9.0-rc5-syzkaller-01489-gdcc61472534e #0 Not tainted
-----------------------------
net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
6 locks held by syz-executor.1/9144:
#0: ffff8880623401a0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:146 [inline]
#0: ffff8880623401a0 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x1be/0xd60 mm/mmap.c:3251
#1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:285
#2: ffff888069870b58 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff888069870b58 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:373
#3: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#3: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#3: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: page_ext_get+0x20/0x2a0 mm/page_ext.c:508
#4: ffffc90000a08c00 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1790
#5: ffff888022c6ccb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#5: ffff888022c6ccb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
stack backtrace:
CPU: 1 PID: 9144 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller-01489-gdcc61472534e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712
nbp_vlan_group net/bridge/br_private.h:1599 [inline]
br_mst_set_state+0x1ea/0x650 net/bridge/br_mst.c:105
br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47
br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88
call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793
expire_timers kernel/time/timer.c:1844 [inline]
__run_timers kernel/time/timer.c:2418 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429
run_timer_base kernel/time/timer.c:2438 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448
__do_softirq+0x2c6/0x980 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:page_ext_get+0x1d1/0x2a0 mm/page_ext.c:510
Code: 6b 8f ff 44 89 fb 83 e3 01 31 ff 48 89 de e8 e6 6f 8f ff 4d 85 ff 74 1c 48 85 db 75 17 4c 0f af 25 24 ba 73 12 4d 01 e7 74 11 ea 6a 8f ff e9 9d 00 00 00 e8 e0 6a 8f ff eb 05 e8 d9 6a 8f ff
RSP: 0018:ffffc9000c6a72a8 EFLAGS: 00000286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888020aa9e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000001a0 R08: ffffffff8206b14a R09: 1ffffffff25e82a0
R10: dffffc0000000000 R11: fffffbfff25e82a1 R12: 00000000022bba90
R13: 800000006f255007 R14: ffffffff8206afb0 R15: ffff888018a3ba90
page_table_check_clear+0x59/0x730 mm/page_table_check.c:72
get_and_clear_full_ptes include/linux/pgtable.h:634 [inline]
zap_present_folio_ptes mm/memory.c:1479 [inline]
zap_present_ptes mm/memory.c:1563 [inline]
zap_pte_range mm/memory.c:1605 [inline]
zap_pmd_range mm/memory.c:1722 [inline]
zap_pud_range mm/memory.c:1751 [inline]
zap_p4d_range mm/memory.c:1772 [inline]
unmap_page_range+0x31b0/0x4820 mm/memory.c:1793
unmap_vmas+0x3cc/0x5f0 mm/memory.c:1883
exit_mmap+0x2cb/0xd60 mm/mmap.c:3267
__mmput+0x115/0x3c0 kernel/fork.c:1346
exit_mm+0x220/0x310 kernel/exit.c:569
do_exit+0x99e/0x27e0 kernel/exit.c:865
do_group_exit+0x207/0x2c0 kernel/exit.c:1027
get_signal+0x16a1/0x1740 kernel/signal.c:2911
arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd0fac7dd29
Code: Unable to access opcode bytes at 0x7fd0fac7dcff.
RSP: 002b:00007fd0fb8fe178 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fd0fadac058 RCX: 00007fd0fac7dd29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd0fadac058
RBP: 00007fd0fadac050 R08: 00007fd0fb8fe6c0 R09: 00007fd0fb8fe6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd0fadac05c
R13: 000000000000006e R14: 00007fff568e4cb0 R15: 00007fff568e4d98
bridge0: port 1(bridge_slave_0) entered learning state
bridge0: port 2(bridge_slave_1) entered learning state
----------------
Code disassembly (best guess):
0: 6b 8f ff 44 89 fb 83 imul $0xffffff83,-0x476bb01(%rdi),%ecx
7: e3 01 jrcxz 0xa
9: 31 ff xor %edi,%edi
b: 48 89 de mov %rbx,%rsi
e: e8 e6 6f 8f ff call 0xff8f6ff9
13: 4d 85 ff test %r15,%r15
16: 74 1c je 0x34
18: 48 85 db test %rbx,%rbx
1b: 75 17 jne 0x34
1d: 4c 0f af 25 24 ba 73 imul 0x1273ba24(%rip),%r12 # 0x1273ba49
24: 12
25: 4d 01 e7 add %r12,%r15
28: 74 11 je 0x3b
* 2a: e8 ea 6a 8f ff call 0xff8f6b19 <-- trapping instruction
2f: e9 9d 00 00 00 jmp 0xd1
34: e8 e0 6a 8f ff call 0xff8f6b19
39: eb 05 jmp 0x40
3b: e8 d9 6a 8f ff call 0xff8f6b19