Warning: Permanently added '10.128.15.197' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 48.245043] kauditd_printk_skb: 2 callbacks suppressed [ 48.245058] audit: type=1400 audit(1567137637.289:36): avc: denied { map } for pid=7626 comm="syz-executor446" path="/root/syz-executor446037457" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 48.292414] [ 48.294051] ======================================================== [ 48.300515] WARNING: possible irq lock inversion dependency detected [ 48.306991] 4.19.69 #43 Not tainted [ 48.310654] -------------------------------------------------------- [ 48.317127] swapper/0/0 just changed the state of lock: [ 48.322466] 00000000f6848af7 (&(&ctx->ctx_lock)->rlock){..-.}, at: free_ioctx_users+0x2d/0x490 [ 48.331206] but this lock took another, SOFTIRQ-unsafe lock in the past: [ 48.338017] (&fiq->waitq){+.+.} [ 48.338025] [ 48.338025] [ 48.338025] and interrupts could create inverse lock ordering between them. [ 48.338025] [ 48.352909] [ 48.352909] other info that might help us debug this: [ 48.359550] Possible interrupt unsafe locking scenario: [ 48.359550] [ 48.366457] CPU0 CPU1 [ 48.371097] ---- ---- [ 48.375737] lock(&fiq->waitq); [ 48.379084] local_irq_disable(); [ 48.412731] lock(&(&ctx->ctx_lock)->rlock); [ 48.419747] lock(&fiq->waitq); [ 48.425627] [ 48.428361] lock(&(&ctx->ctx_lock)->rlock); [ 48.433007] [ 48.433007] *** DEADLOCK *** [ 48.433007] [ 48.439045] 2 locks held by swapper/0/0: [ 48.443093] #0: 000000008716d2bd (rcu_callback){....}, at: rcu_process_callbacks+0xc79/0x1a30 [ 48.451844] #1: 000000007ba6b587 (rcu_read_lock_sched){....}, at: percpu_ref_switch_to_atomic_rcu+0x1ca/0x540 [ 48.461978] [ 48.461978] the shortest dependencies between 2nd lock and 1st lock: [ 48.469939] -> (&fiq->waitq){+.+.} ops: 4 { [ 48.474340] HARDIRQ-ON-W at: [ 48.477708] lock_acquire+0x16f/0x3f0 [ 48.483315] _raw_spin_lock+0x2f/0x40 [ 48.488938] flush_bg_queue+0x1f3/0x3d0 [ 48.494714] fuse_request_send_background_locked+0x26d/0x4e0 [ 48.502311] fuse_request_send_background+0x12b/0x180 [ 48.509313] cuse_channel_open+0x5ba/0x830 [ 48.515347] misc_open+0x395/0x4c0 [ 48.520689] chrdev_open+0x245/0x6b0 [ 48.526220] do_dentry_open+0x4c3/0x1210 [ 48.532088] vfs_open+0xa0/0xd0 [ 48.537191] path_openat+0x10d7/0x45e0 [ 48.542882] do_filp_open+0x1a1/0x280 [ 48.548487] do_sys_open+0x3fe/0x550 [ 48.554027] __x64_sys_openat+0x9d/0x100 [ 48.559895] do_syscall_64+0xfd/0x620 [ 48.565501] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.572486] SOFTIRQ-ON-W at: [ 48.575835] lock_acquire+0x16f/0x3f0 [ 48.581435] _raw_spin_lock+0x2f/0x40 [ 48.587041] flush_bg_queue+0x1f3/0x3d0 [ 48.592832] fuse_request_send_background_locked+0x26d/0x4e0 [ 48.600432] fuse_request_send_background+0x12b/0x180 [ 48.607427] cuse_channel_open+0x5ba/0x830 [ 48.613463] misc_open+0x395/0x4c0 [ 48.618803] chrdev_open+0x245/0x6b0 [ 48.624320] do_dentry_open+0x4c3/0x1210 [ 48.630183] vfs_open+0xa0/0xd0 [ 48.635450] path_openat+0x10d7/0x45e0 [ 48.641138] do_filp_open+0x1a1/0x280 [ 48.646740] do_sys_open+0x3fe/0x550 [ 48.652259] __x64_sys_openat+0x9d/0x100 [ 48.658122] do_syscall_64+0xfd/0x620 [ 48.663750] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.670739] INITIAL USE at: [ 48.674003] lock_acquire+0x16f/0x3f0 [ 48.679529] _raw_spin_lock+0x2f/0x40 [ 48.685059] flush_bg_queue+0x1f3/0x3d0 [ 48.690758] fuse_request_send_background_locked+0x26d/0x4e0 [ 48.698269] fuse_request_send_background+0x12b/0x180 [ 48.705192] cuse_channel_open+0x5ba/0x830 [ 48.711345] misc_open+0x395/0x4c0 [ 48.716611] chrdev_open+0x245/0x6b0 [ 48.722042] do_dentry_open+0x4c3/0x1210 [ 48.727815] vfs_open+0xa0/0xd0 [ 48.732812] path_openat+0x10d7/0x45e0 [ 48.738411] do_filp_open+0x1a1/0x280 [ 48.743923] do_sys_open+0x3fe/0x550 [ 48.749349] __x64_sys_openat+0x9d/0x100 [ 48.755125] do_syscall_64+0xfd/0x620 [ 48.760643] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.767545] } [ 48.769419] ... key at: [] __key.42211+0x0/0x40 [ 48.776229] ... acquired at: [ 48.779398] _raw_spin_lock+0x2f/0x40 [ 48.783348] io_submit_one+0xef2/0x2eb0 [ 48.787472] __x64_sys_io_submit+0x1aa/0x520 [ 48.792034] do_syscall_64+0xfd/0x620 [ 48.795998] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.801333] [ 48.802936] -> (&(&ctx->ctx_lock)->rlock){..-.} ops: 2 { [ 48.808371] IN-SOFTIRQ-W at: [ 48.811639] lock_acquire+0x16f/0x3f0 [ 48.817068] _raw_spin_lock_irq+0x60/0x80 [ 48.822861] free_ioctx_users+0x2d/0x490 [ 48.828568] percpu_ref_switch_to_atomic_rcu+0x407/0x540 [ 48.835664] rcu_process_callbacks+0xba0/0x1a30 [ 48.841973] __do_softirq+0x25c/0x921 [ 48.847425] irq_exit+0x180/0x1d0 [ 48.852509] smp_apic_timer_interrupt+0x13b/0x550 [ 48.858998] apic_timer_interrupt+0xf/0x20 [ 48.864863] native_safe_halt+0xe/0x10 [ 48.870401] arch_cpu_idle+0xa/0x10 [ 48.875661] default_idle_call+0x36/0x90 [ 48.881349] do_idle+0x377/0x560 [ 48.886341] cpu_startup_entry+0xc8/0xe0 [ 48.892054] rest_init+0x219/0x222 [ 48.897225] start_kernel+0x88c/0x8c5 [ 48.902744] x86_64_start_reservations+0x29/0x2b [ 48.909127] x86_64_start_kernel+0x77/0x7b [ 48.915028] secondary_startup_64+0xa4/0xb0 [ 48.921081] INITIAL USE at: [ 48.924261] lock_acquire+0x16f/0x3f0 [ 48.929609] _raw_spin_lock_irq+0x60/0x80 [ 48.935300] io_submit_one+0xead/0x2eb0 [ 48.940816] __x64_sys_io_submit+0x1aa/0x520 [ 48.946765] do_syscall_64+0xfd/0x620 [ 48.952131] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.958860] } [ 48.960646] ... key at: [] __key.50211+0x0/0x40 [ 48.967376] ... acquired at: [ 48.970459] mark_lock+0x420/0x1370 [ 48.974235] __lock_acquire+0xc62/0x49c0 [ 48.978446] lock_acquire+0x16f/0x3f0 [ 48.982412] _raw_spin_lock_irq+0x60/0x80 [ 48.986725] free_ioctx_users+0x2d/0x490 [ 48.990938] percpu_ref_switch_to_atomic_rcu+0x407/0x540 [ 48.996540] rcu_process_callbacks+0xba0/0x1a30 [ 49.001365] __do_softirq+0x25c/0x921 [ 49.005331] irq_exit+0x180/0x1d0 [ 49.008936] smp_apic_timer_interrupt+0x13b/0x550 [ 49.013932] apic_timer_interrupt+0xf/0x20 [ 49.018318] native_safe_halt+0xe/0x10 [ 49.022359] arch_cpu_idle+0xa/0x10 [ 49.026140] default_idle_call+0x36/0x90 [ 49.030352] do_idle+0x377/0x560 [ 49.034912] cpu_startup_entry+0xc8/0xe0 [ 49.039129] rest_init+0x219/0x222 [ 49.042823] start_kernel+0x88c/0x8c5 [ 49.046775] x86_64_start_reservations+0x29/0x2b [ 49.051684] x86_64_start_kernel+0x77/0x7b [ 49.056073] secondary_startup_64+0xa4/0xb0 [ 49.060565] [ 49.062166] [ 49.062166] stack backtrace: [ 49.066642] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.69 #43 [ 49.072849] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.082178] Call Trace: [ 49.084740] [ 49.086875] dump_stack+0x172/0x1f0 [ 49.090495] print_irq_inversion_bug.part.0+0x2c0/0x2cd [ 49.095847] check_usage_forwards.cold+0x20/0x29 [ 49.100594] ? check_usage_backwards+0x340/0x340 [ 49.105418] ? save_stack_trace+0x1a/0x20 [ 49.109553] ? save_trace+0xe0/0x290 [ 49.113245] mark_lock+0x420/0x1370 [ 49.116860] ? check_usage_backwards+0x340/0x340 [ 49.121595] __lock_acquire+0xc62/0x49c0 [ 49.125636] ? mark_held_locks+0x100/0x100 [ 49.129853] ? mark_held_locks+0x100/0x100 [ 49.134083] ? __wake_up_common_lock+0xfe/0x190 [ 49.138738] ? mark_held_locks+0x100/0x100 [ 49.142973] ? __wake_up_common_lock+0xfe/0x190 [ 49.152150] ? _raw_spin_unlock_irqrestore+0x6b/0xe0 [ 49.157235] ? lockdep_hardirqs_on+0x19b/0x5d0 [ 49.161821] ? trace_hardirqs_on+0x67/0x220 [ 49.166139] ? kasan_check_read+0x11/0x20 [ 49.171060] lock_acquire+0x16f/0x3f0 [ 49.174843] ? free_ioctx_users+0x2d/0x490 [ 49.179058] _raw_spin_lock_irq+0x60/0x80 [ 49.183186] ? free_ioctx_users+0x2d/0x490 [ 49.187399] free_ioctx_users+0x2d/0x490 [ 49.191441] ? rcu_dynticks_curr_cpu_in_eqs+0x51/0xb0 [ 49.196613] percpu_ref_switch_to_atomic_rcu+0x407/0x540 [ 49.202130] ? percpu_ref_exit+0xd0/0xd0 [ 49.206185] rcu_process_callbacks+0xba0/0x1a30 [ 49.210835] ? __rcu_read_unlock+0x170/0x170 [ 49.215230] __do_softirq+0x25c/0x921 [ 49.219008] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 49.224524] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 49.230043] irq_exit+0x180/0x1d0 [ 49.233482] smp_apic_timer_interrupt+0x13b/0x550 [ 49.238313] apic_timer_interrupt+0xf/0x20 [ 49.242521] [ 49.244738] RIP: 0010:native_safe_halt+0xe/0x10 [ 49.249390] Code: ff ff 48 89 df e8 02 2c ae fa eb 82 e9 07 00 00 00 0f 00 2d 84 1e 54 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 74 1e 54 00 fb f4 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 4e 0e 66 fa e8 09 [ 49.268286] RSP: 0018:ffffffff88607ca8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 49.275981] RAX: 1ffffffff10e48c4 RBX: ffffffff88679ec0 RCX: 0000000000000000 [ 49.283249] RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff8867a73c [ 49.290504] RBP: ffffffff88607cd8 R08: ffffffff88679ec0 R09: 0000000000000000 [ 49.297754] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 49.305001] R13: ffffffff88724610 R14: 0000000000000000 R15: 0000000000000000 [ 49.312266] ? default_idle+0x4e/0x320 [ 49.316139] arch_cpu_idle+0xa/0x10 [ 49.319745] default_idle_call+0x36/0x90 [ 49.323785] do_idle+0x377/0x560 [ 49.327126] ? arch_cpu_idle_exit+0x80/0x80 [ 49.331431] ? check_preemption_disabled+0x48/0x290 [ 49.336427] cpu_startup_entry+0xc8/0xe0 [ 49.340465] ? cpu_in_idle+0x20/0x20 [ 49.344177] rest_init+0x219/0x222 [ 49.347705] start_kernel+0x88c/0x8c5 [ 49.351491] ? mem_encrypt_init+0xb/0xb [ 49.355462] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 49.361014] ? x86_family+0x41/0x50 [ 49.364624]