Warning: Permanently added '10.128.0.247' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program [ 30.362753] [ 30.362756] ============================================ [ 30.362757] WARNING: possible recursive locking detected [ 30.362760] 4.14.222-syzkaller #0 Not tainted [ 30.362761] -------------------------------------------- [ 30.362764] syz-executor274/7987 is trying to acquire lock: [ 30.362766] ((fb_notifier_list).rwsem){++++}, at: [] blocking_notifier_call_chain+0x63/0x90 [ 30.362781] [ 30.362781] but task is already holding lock: [ 30.362781] ((fb_notifier_list).rwsem){++++}, at: [] blocking_notifier_call_chain+0x63/0x90 [ 30.362788] [ 30.362788] other info that might help us debug this: [ 30.362789] Possible unsafe locking scenario: [ 30.362789] [ 30.362790] CPU0 [ 30.362791] ---- [ 30.362791] lock((fb_notifier_list).rwsem); [ 30.362794] lock((fb_notifier_list).rwsem); [ 30.362796] [ 30.362796] *** DEADLOCK *** [ 30.362796] [ 30.362797] May be due to missing lock nesting notation [ 30.362797] [ 30.362799] 3 locks held by syz-executor274/7987: [ 30.362800] #0: (console_lock){+.+.}, at: [] do_fb_ioctl+0x81a/0xa70 [ 30.362813] #1: (&fb_info->lock){+.+.}, at: [] do_fb_ioctl+0x824/0xa70 [ 30.362820] #2: ((fb_notifier_list).rwsem){++++}, at: [] blocking_notifier_call_chain+0x63/0x90 [ 30.362827] [ 30.362827] stack backtrace: [ 30.362830] CPU: 0 PID: 7987 Comm: syz-executor274 Not tainted 4.14.222-syzkaller #0 [ 30.362833] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.362834] Call Trace: [ 30.362845] dump_stack+0x1b2/0x281 [ 30.362851] __lock_acquire.cold+0x180/0x97c [ 30.362858] ? trace_hardirqs_on+0x10/0x10 [ 30.362865] ? check_preemption_disabled+0x35/0x240 [ 30.362869] ? delay_tsc+0x8a/0xb0 [ 30.362874] ? vga16fb_update_fix+0x2fe/0x470 [ 30.362878] ? memcpy+0x35/0x50 [ 30.362882] lock_acquire+0x170/0x3f0 [ 30.362886] ? blocking_notifier_call_chain+0x63/0x90 [ 30.362891] down_read+0x36/0x80 [ 30.362895] ? blocking_notifier_call_chain+0x63/0x90 [ 30.362899] blocking_notifier_call_chain+0x63/0x90 [ 30.362903] fb_set_var+0xac5/0xc90 [ 30.362906] ? fb_set_suspend+0x110/0x110 [ 30.362913] ? kfree+0xc9/0x250 [ 30.362918] ? vga16fb_imageblit+0x630/0x2140 [ 30.362922] ? fb_pad_aligned_buffer+0xbf/0x110 [ 30.362927] ? bit_cursor+0xfb8/0x1580 [ 30.362931] ? fb_videomode_to_var+0xf/0x610 [ 30.362934] fbcon_switch+0x3d9/0x19e0 [ 30.362939] ? fbcon_event_notify+0x1760/0x1760 [ 30.362947] redraw_screen+0x32c/0x790 [ 30.362952] ? get_color+0x1be/0x3a0 [ 30.362955] ? con_shutdown+0x90/0x90 [ 30.362958] ? bit_update_start+0x1f0/0x1f0 [ 30.362961] ? fbcon_cursor+0x480/0x640 [ 30.362964] fbcon_blank+0x986/0xd50 [ 30.362968] ? con2fb_release_oldinfo.constprop.0+0x5a0/0x5a0 [ 30.362971] ? __lock_acquire+0x5fc/0x3f20 [ 30.362975] ? __mutex_lock+0x356/0x1310 [ 30.362979] ? trace_hardirqs_on+0x10/0x10 [ 30.362983] ? __lock_acquire+0x5fc/0x3f20 [ 30.362988] do_unblank_screen+0x1fd/0x4e0 [ 30.362992] fbcon_event_notify+0x1445/0x1760 [ 30.362996] notifier_call_chain+0x108/0x1a0 [ 30.363001] blocking_notifier_call_chain+0x79/0x90 [ 30.363004] fb_blank+0x14c/0x190 [ 30.363008] ? fb_set_logocmap+0x450/0x450 [ 30.363011] ? do_fb_ioctl+0x81a/0xa70 [ 30.363016] do_fb_ioctl+0x894/0xa70 [ 30.363022] ? register_framebuffer+0x8e0/0x8e0 [ 30.363027] ? __kernel_text_address+0x9/0x30 [ 30.363036] ? unwind_get_return_address+0x51/0x90 [ 30.363042] ? entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.363049] ? __save_stack_trace+0xa0/0x160 [ 30.363057] ? check_preemption_disabled+0x35/0x240 [ 30.363063] ? kasan_slab_free+0x12d/0x1a0 [ 30.363069] ? kasan_slab_free+0xc3/0x1a0 [ 30.363075] ? kmem_cache_free+0x7c/0x2b0 [ 30.363082] ? putname+0xcd/0x110 [ 30.363088] ? do_sys_open+0x203/0x410 [ 30.363095] ? do_syscall_64+0x1d5/0x640 [ 30.363102] ? entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.363109] ? path_lookupat+0x780/0x780 [ 30.363116] ? debug_check_no_obj_freed+0x2c0/0x680 [ 30.363123] ? lock_acquire+0x170/0x3f0 [ 30.363127] ? lock_downgrade+0x740/0x740 [ 30.363132] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 30.363136] ? debug_check_no_obj_freed+0x2c0/0x680 [ 30.363140] fb_ioctl+0xdd/0x130 [ 30.363143] ? do_fb_ioctl+0xa70/0xa70 [ 30.363146] do_vfs_ioctl+0x75a/0xff0 [ 30.363152] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 30.363155] ? ioctl_preallocate+0x1a0/0x1a0 [ 30.363158] ? kmem_cache_free+0x23a/0x2b0 [ 30.363162] ? putname+0xcd/0x110 [ 30.363165] ? do_sys_open+0x208/0x410 [ 30.363168] ? filp_open+0x60/0x60 [ 30.363174] ? security_file_ioctl+0x83/0xb0 [ 30.363177] SyS_ioctl+0x7f/0xb0 [ 30.363180] ? do_vfs_ioctl+0xff0/0xff0 [ 30.363183] do_syscall_64+0x1d5/0x640 [ 30.363188] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.363192] RIP: 0033:0x440119 [ 30.363194] RSP: 002b:00007ffd7a421db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 30.363199] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 0000000000440119 [ 30.363201] RDX: 0000000000000000 RSI: 0000000000004611 RDI: 0000000000000006 [ 30.363203] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 executing program [ 30.363205] R10: 0000000000000001 R11: 0000000000000246 R12: 00000000004038f0 [ 30.363207] R13: 0000000000000000 R14: 00007ffd7a421de0 R15: 00007ffd7a421dd0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program