=============================
WARNING: suspicious RCU usage
6.9.0-rc7-syzkaller-00113-ga2c78977950d #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
5 locks held by syz-executor.3/13177:
#0: ffffffff8e3df4f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:637 [inline]
#0: ffffffff8e3df4f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1688 [inline]
#0: ffffffff8e3df4f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x275/0x2180 kernel/fork.c:1737
#1: ffff88807d104da0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:124 [inline]
#1: ffff88807d104da0 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:638 [inline]
#1: ffff88807d104da0 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1688 [inline]
#1: ffff88807d104da0 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x295/0x2180 kernel/fork.c:1737
#2: ffff8880200b3aa0 (&mm->mmap_lock/1){+.+.}-{3:3}, at: mmap_write_lock_nested include/linux/mmap_lock.h:115 [inline]
#2: ffff8880200b3aa0 (&mm->mmap_lock/1){+.+.}-{3:3}, at: dup_mmap kernel/fork.c:647 [inline]
#2: ffff8880200b3aa0 (&mm->mmap_lock/1){+.+.}-{3:3}, at: dup_mm kernel/fork.c:1688 [inline]
#2: ffff8880200b3aa0 (&mm->mmap_lock/1){+.+.}-{3:3}, at: copy_mm+0x3d1/0x2180 kernel/fork.c:1737
#3: ffffc90000007be0 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1790
#4: ffff88805b940cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#4: ffff88805b940cb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
stack backtrace:
CPU: 0 PID: 13177 Comm: syz-executor.3 Not tainted 6.9.0-rc7-syzkaller-00113-ga2c78977950d #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+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
handle_softirqs+0x2d6/0x990 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
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:unwind_next_frame+0x6e/0x2a00 arch/x86/kernel/unwind_orc.c:470
Code: b9 00 48 89 5c 24 20 4c 8b 7d 48 48 8d 5d 38 48 89 d8 48 c1 e8 03 48 89 44 24 58 42 80 3c 28 00 74 08 48 89 df e8 32 74 b9 00 <48> 8b 45 38 48 89 84 24 90 00 00 00 48 89 e8 48 c1 e8 03 48 89 44
RSP: 0018:ffffc9000a2869a8 EFLAGS: 00000246
RAX: 1ffff92001450d57 RBX: ffffc9000a286ab8 RCX: ffff8880214d9e00
RDX: 0000000000000000 RSI: ffffffff8b7feba5 RDI: ffffc9000a286a80
RBP: ffffc9000a286a80 R08: 000000000000000a R09: ffffc9000a286b70
R10: 0000000000000003 R11: ffffffff8181e7c0 R12: ffff8880214d9e00
R13: dffffc0000000000 R14: ffffc9000a286b60 R15: ffffffff8b7feba5
arch_stack_walk+0x151/0x1b0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
save_stack+0xfb/0x1f0 mm/page_owner.c:156
__set_page_owner+0x8d/0x810 mm/page_owner.c:325
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
prep_new_page mm/page_alloc.c:1541 [inline]
get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
__alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
alloc_pages_mpol+0x3e8/0x680 mm/mempolicy.c:2264
pagetable_alloc include/linux/mm.h:2864 [inline]
__pud_alloc_one include/asm-generic/pgalloc.h:169 [inline]
pud_alloc_one include/asm-generic/pgalloc.h:189 [inline]
__pud_alloc+0x93/0x4b0 mm/memory.c:5828
pud_alloc include/linux/mm.h:2821 [inline]
copy_pud_range mm/memory.c:1255 [inline]
copy_p4d_range mm/memory.c:1299 [inline]
copy_page_range+0x54fa/0x5b00 mm/memory.c:1397
dup_mmap kernel/fork.c:751 [inline]
dup_mm kernel/fork.c:1688 [inline]
copy_mm+0x1321/0x2180 kernel/fork.c:1737
copy_process+0x187a/0x3df0 kernel/fork.c:2390
kernel_clone+0x226/0x8f0 kernel/fork.c:2797
__do_sys_clone kernel/fork.c:2940 [inline]
__se_sys_clone kernel/fork.c:2924 [inline]
__x64_sys_clone+0x258/0x2a0 kernel/fork.c:2924
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f050747ad93
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007fff253ada98 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f050747ad93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000555563711750 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
bridge0: port 1(bridge_slave_0) entered learning state
bridge0: port 2(bridge_slave_1) entered learning state
----------------
Code disassembly (best guess):
0: b9 00 48 89 5c mov $0x5c894800,%ecx
5: 24 20 and $0x20,%al
7: 4c 8b 7d 48 mov 0x48(%rbp),%r15
b: 48 8d 5d 38 lea 0x38(%rbp),%rbx
f: 48 89 d8 mov %rbx,%rax
12: 48 c1 e8 03 shr $0x3,%rax
16: 48 89 44 24 58 mov %rax,0x58(%rsp)
1b: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
20: 74 08 je 0x2a
22: 48 89 df mov %rbx,%rdi
25: e8 32 74 b9 00 call 0xb9745c
* 2a: 48 8b 45 38 mov 0x38(%rbp),%rax <-- trapping instruction
2e: 48 89 84 24 90 00 00 mov %rax,0x90(%rsp)
35: 00
36: 48 89 e8 mov %rbp,%rax
39: 48 c1 e8 03 shr $0x3,%rax
3d: 48 rex.W
3e: 89 .byte 0x89
3f: 44 rex.R