program: r0 = socket$inet6_tcp(0xa, 0x1, 0x0) close(r0) socket(0x2b, 0x1, 0x1) bind$inet6(r0, &(0x7f0000000040)={0xa, 0x4e22, 0x0, @empty}, 0x1c) listen(r0, 0x0) r1 = socket$inet_mptcp(0x2, 0x1, 0x106) connect$inet(r1, &(0x7f0000000000)={0x2, 0x4e22, @local}, 0x10) r2 = seccomp$SECCOMP_SET_MODE_FILTER_LISTENER(0x1, 0x0, &(0x7f0000000400)={0x1, &(0x7f0000000380)=[{0x6, 0x0, 0x0, 0x7fffffff}]}) r3 = socket$unix(0x1, 0x5, 0x0) r4 = dup2(r3, r2) close_range(r4, 0xffffffffffffffff, 0x0) [ 68.410074][ T5305] Bluetooth: hci0: command tx timeout [ 68.468495][ T5322] [ 68.469410][ T5322] ====================================================== [ 68.471981][ T5322] WARNING: possible circular locking dependency detected [ 68.474915][ T5322] 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0 Not tainted [ 68.477794][ T5322] ------------------------------------------------------ [ 68.480499][ T5322] syz.0.0/5322 is trying to acquire lock: [ 68.482832][ T5322] ffff88803eef94d0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xe9/0xc60 [ 68.487552][ T5322] [ 68.487552][ T5322] but task is already holding lock: [ 68.490297][ T5322] ffff88803eef8258 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 [ 68.493939][ T5322] [ 68.493939][ T5322] which lock already depends on the new lock. [ 68.493939][ T5322] [ 68.497994][ T5322] [ 68.497994][ T5322] the existing dependency chain (in reverse order) is: [ 68.501299][ T5322] [ 68.501299][ T5322] -> #1 (sk_lock-AF_SMC/1){+.+.}-{0:0}: [ 68.504351][ T5322] lock_acquire+0x1ed/0x550 [ 68.506385][ T5322] lock_sock_nested+0x48/0x100 [ 68.508472][ T5322] smc_listen_out+0x11b/0x3e0 [ 68.510378][ T5322] process_scheduled_works+0xabe/0x18e0 [ 68.512757][ T5322] worker_thread+0x870/0xd30 [ 68.514847][ T5322] kthread+0x7a9/0x920 [ 68.516694][ T5322] ret_from_fork+0x4b/0x80 [ 68.518465][ T5322] ret_from_fork_asm+0x1a/0x30 [ 68.520589][ T5322] [ 68.520589][ T5322] -> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}: [ 68.524703][ T5322] validate_chain+0x18ef/0x5920 [ 68.526904][ T5322] __lock_acquire+0x1397/0x2100 [ 68.529090][ T5322] lock_acquire+0x1ed/0x550 [ 68.531101][ T5322] __flush_work+0x739/0xc60 [ 68.533029][ T5322] __cancel_work_sync+0xbc/0x110 [ 68.535191][ T5322] smc_clcsock_release+0x62/0xf0 [ 68.537484][ T5322] __smc_release+0x683/0x800 [ 68.539409][ T5322] smc_close_non_accepted+0xd8/0x1f0 [ 68.541703][ T5322] smc_close_active+0xadb/0xe90 [ 68.543860][ T5322] __smc_release+0xa0/0x800 [ 68.545868][ T5322] smc_release+0x2dc/0x540 [ 68.547910][ T5322] sock_close+0xbc/0x240 [ 68.549880][ T5322] __fput+0x3e9/0x9f0 [ 68.551736][ T5322] task_work_run+0x24f/0x310 [ 68.553822][ T5322] syscall_exit_to_user_mode+0x13f/0x340 [ 68.556460][ T5322] do_syscall_64+0x100/0x230 [ 68.558459][ T5322] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 68.561023][ T5322] [ 68.561023][ T5322] other info that might help us debug this: [ 68.561023][ T5322] [ 68.565287][ T5322] Possible unsafe locking scenario: [ 68.565287][ T5322] [ 68.568744][ T5322] CPU0 CPU1 [ 68.570845][ T5322] ---- ---- [ 68.573009][ T5322] lock(sk_lock-AF_SMC/1); [ 68.574806][ T5322] lock((work_completion)(&new_smc->smc_listen_work)); [ 68.578394][ T5322] lock(sk_lock-AF_SMC/1); [ 68.581072][ T5322] lock((work_completion)(&new_smc->smc_listen_work)); [ 68.583935][ T5322] [ 68.583935][ T5322] *** DEADLOCK *** [ 68.583935][ T5322] [ 68.587036][ T5322] 3 locks held by syz.0.0/5322: [ 68.588950][ T5322] #0: ffff888043baa008 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 [ 68.592909][ T5322] #1: ffff88803eef8258 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 [ 68.596949][ T5322] #2: ffffffff8eb39320 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xe9/0xc60 [ 68.600607][ T5322] [ 68.600607][ T5322] stack backtrace: [ 68.602982][ T5322] CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.14.0-rc5-syzkaller-00214-g21e4543a2e2f #0 [ 68.602997][ T5322] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 68.603005][ T5322] Call Trace: [ 68.603012][ T5322] [ 68.603018][ T5322] dump_stack_lvl+0x241/0x360 [ 68.603043][ T5322] ? __pfx_dump_stack_lvl+0x10/0x10 [ 68.603057][ T5322] ? __pfx__printk+0x10/0x10 [ 68.603070][ T5322] print_circular_bug+0x13a/0x1b0 [ 68.603085][ T5322] check_noncircular+0x36a/0x4a0 [ 68.603097][ T5322] ? __pfx_check_noncircular+0x10/0x10 [ 68.603108][ T5322] ? lockdep_lock+0x123/0x2b0 [ 68.603124][ T5322] validate_chain+0x18ef/0x5920 [ 68.603139][ T5322] ? __pfx_validate_chain+0x10/0x10 [ 68.603154][ T5322] ? look_up_lock_class+0x77/0x170 [ 68.603170][ T5322] ? register_lock_class+0x102/0x980 [ 68.603186][ T5322] ? __pfx_register_lock_class+0x10/0x10 [ 68.603200][ T5322] ? do_raw_spin_lock+0x14f/0x370 [ 68.603212][ T5322] ? __pfx_lock_release+0x10/0x10 [ 68.603227][ T5322] ? mark_lock+0x9a/0x360 [ 68.603237][ T5322] __lock_acquire+0x1397/0x2100 [ 68.603253][ T5322] ? _raw_spin_unlock_irqrestore+0xdd/0x140 [ 68.603268][ T5322] lock_acquire+0x1ed/0x550 [ 68.603282][ T5322] ? __flush_work+0xe9/0xc60 [ 68.603298][ T5322] ? __pfx_lock_acquire+0x10/0x10 [ 68.603312][ T5322] ? lockdep_hardirqs_on_prepare+0x43d/0x780 [ 68.603326][ T5322] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 68.603342][ T5322] ? _raw_spin_unlock_irq+0x23/0x50 [ 68.603354][ T5322] ? __flush_work+0xe9/0xc60 [ 68.603369][ T5322] __flush_work+0x739/0xc60 [ 68.603390][ T5322] ? __flush_work+0xe9/0xc60 [ 68.603405][ T5322] ? __flush_work+0xe9/0xc60 [ 68.603420][ T5322] ? __pfx___flush_work+0x10/0x10 [ 68.603434][ T5322] ? __pfx_wq_barrier_func+0x10/0x10 [ 68.603449][ T5322] ? __pfx___cancel_work+0x10/0x10 [ 68.603491][ T5322] ? __local_bh_enable_ip+0x168/0x200 [ 68.603507][ T5322] ? __smc_release+0x67b/0x800 [ 68.603519][ T5322] ? __pfx___local_bh_enable_ip+0x10/0x10 [ 68.603531][ T5322] ? __smc_release+0x67b/0x800 [ 68.603542][ T5322] __cancel_work_sync+0xbc/0x110 [ 68.603557][ T5322] smc_clcsock_release+0x62/0xf0 [ 68.603572][ T5322] __smc_release+0x683/0x800 [ 68.603584][ T5322] smc_close_non_accepted+0xd8/0x1f0 [ 68.603598][ T5322] smc_close_active+0xadb/0xe90 [ 68.603612][ T5322] ? __pfx_sock_def_readable+0x10/0x10 [ 68.603627][ T5322] __smc_release+0xa0/0x800 [ 68.603640][ T5322] smc_release+0x2dc/0x540 [ 68.603652][ T5322] sock_close+0xbc/0x240 [ 68.603665][ T5322] ? __pfx_sock_close+0x10/0x10 [ 68.603677][ T5322] __fput+0x3e9/0x9f0 [ 68.603694][ T5322] task_work_run+0x24f/0x310 [ 68.603705][ T5322] ? _raw_spin_unlock+0x28/0x50 [ 68.603718][ T5322] ? __pfx_task_work_run+0x10/0x10 [ 68.603728][ T5322] ? syscall_exit_to_user_mode+0xa3/0x340 [ 68.603745][ T5322] syscall_exit_to_user_mode+0x13f/0x340 [ 68.603760][ T5322] do_syscall_64+0x100/0x230 [ 68.603774][ T5322] ? clear_bhb_loop+0x35/0x90 [ 68.603788][ T5322] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 68.603802][ T5322] RIP: 0033:0x7f9c79d8d169 [ 68.603813][ T5322] Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 [ 68.603822][ T5322] RSP: 002b:00007f9c761f5038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 [ 68.603834][ T5322] RAX: 0000000000000000 RBX: 00007f9c79fa5fa0 RCX: 00007f9c79d8d169 [ 68.603841][ T5322] RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000000 [ 68.603848][ T5322] RBP: 00007f9c79e0e2a0 R08: 0000000000000000 R09: 0000000000000000 [ 68.603854][ T5322] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 68.603861][ T5322] R13: 0000000000000000 R14: 00007f9c79fa5fa0 R15: 00007ffc3cfbf908 [ 68.603873][ T5322]