------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff88802b0db090 object type: timer_list hint: rose_t0timer_expiry+0x0/0x150 include/linux/skbuff.h:2928 WARNING: lib/debugobjects.c:612 at debug_print_object+0x18e/0x2a0 lib/debugobjects.c:612, CPU#1: kworker/u32:30/7978 Modules linked in: CPU: 1 UID: 0 PID: 7978 Comm: kworker/u32:30 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:debug_print_object+0x19b/0x2a0 lib/debugobjects.c:612 Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 48 8d 3d 72 78 ee 0b 41 56 48 8b 14 dd 60 ec 1a 8c 4c 89 e6 <67> 48 0f b9 3a 58 83 05 9c 48 e4 0b 01 48 83 c4 18 5b 5d 41 5c 41 RSP: 0018:ffffc900006a0a58 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: ffffffff8c1aeba0 RSI: ffffffff8c1ae7c0 RDI: ffffffff90e333c0 RBP: 0000000000000001 R08: ffff88802b0db090 R09: ffffffff8bb2c880 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8c1ae7c0 R13: ffffffff8bb2c8c0 R14: ffffffff8a6eed50 R15: ffffc900006a0b58 FS: 0000000000000000(0000) GS:ffff8880d648b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005636004349f0 CR3: 000000000e596000 CR4: 0000000000352ef0 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline] debug_check_no_obj_freed+0x4da/0x630 lib/debugobjects.c:1129 slab_free_hook mm/slub.c:2601 [inline] slab_free mm/slub.c:6082 [inline] kfree+0x343/0x670 mm/slub.c:6399 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183 call_timer_fn+0x19a/0x590 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x757/0xac0 kernel/time/timer.c:2373 __run_timer_base kernel/time/timer.c:2385 [inline] __run_timer_base kernel/time/timer.c:2377 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2394 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2404 handle_softirqs+0x1ea/0x910 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xac/0xe0 kernel/softirq.c:510 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:395 [inline] cfg80211_inform_single_bss_data+0x959/0x1d40 net/wireless/scan.c:2389 cfg80211_inform_bss_data+0x237/0x3a00 net/wireless/scan.c:3228 cfg80211_inform_bss_frame_data+0x247/0x730 net/wireless/scan.c:3319 ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:230 ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline] ieee80211_ibss_rx_queued_mgmt+0x1919/0x2f20 net/mac80211/ibss.c:1602 ieee80211_iface_process_skb net/mac80211/iface.c:1748 [inline] ieee80211_iface_work+0xbff/0x13d0 net/mac80211/iface.c:1802 cfg80211_wiphy_work+0x3f7/0x560 net/wireless/core.c:440 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: b8 00 00 00 00 mov $0x0,%eax 5: 00 fc add %bh,%ah 7: ff lcall (bad) 8: df 48 89 fisttps -0x77(%rax) b: fa cli c: 48 c1 ea 03 shr $0x3,%rdx 10: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 14: 75 4f jne 0x65 16: 48 8d 3d 72 78 ee 0b lea 0xbee7872(%rip),%rdi # 0xbee788f 1d: 41 56 push %r14 1f: 48 8b 14 dd 60 ec 1a mov -0x73e513a0(,%rbx,8),%rdx 26: 8c 27: 4c 89 e6 mov %r12,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 58 pop %rax 30: 83 05 9c 48 e4 0b 01 addl $0x1,0xbe4489c(%rip) # 0xbe448d3 37: 48 83 c4 18 add $0x18,%rsp 3b: 5b pop %rbx 3c: 5d pop %rbp 3d: 41 5c pop %r12 3f: 41 rex.B