audit: type=1326 audit(1531402732.130:3): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=18394 comm="syz-executor0" exe="/root/syz-executor0" sig=9 arch=c000003e syscall=202 compat=0 ip=0x455a79 code=0x0 audit: type=1326 audit(1531402732.191:4): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=18394 comm="syz-executor0" exe="/root/syz-executor0" sig=9 arch=c000003e syscall=202 compat=0 ip=0x455a79 code=0x0 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN CPU: 1 PID: 18405 Comm: syz-executor5 Not tainted 4.18.0-rc4+ #143 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:83 Code: 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 48 8b 9b 48 12 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 38 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 51 44 8b 63 38 31 ff 41 83 e4 01 RSP: 0018:ffff880199666688 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90007437000 RDX: 0000000000000007 RSI: ffffffff817d1c51 RDI: 0000000000000038 RBP: ffff8801996666a0 R08: ffffed003b5e46d7 R09: 0000000000000000 R10: ffff8801996667b0 R11: ffff8801daf236b3 R12: ffff8801d86b4340 R13: ffff8801986bc040 R14: ffff8801986bc07c R15: 0000000000000002 FS: 00007f9ae1e21700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ae1e41c88 CR3: 00000001d96b4000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: delayacct_blkio_end include/linux/delayacct.h:128 [inline] try_to_wake_up+0xacb/0x12b0 kernel/sched/core.c:2056 default_wake_function+0x30/0x50 kernel/sched/core.c:3739 autoremove_wake_function+0x80/0x370 kernel/sched/wait.c:373 wake_page_function+0x15f/0x1c0 mm/filemap.c:1010 __wake_up_common+0x191/0x740 kernel/sched/wait.c:90 __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165 wake_up_page_bit+0x2ab/0x5b0 mm/filemap.c:1030 unlock_page+0x223/0x2c0 mm/filemap.c:1207 do_huge_pmd_wp_page+0x13f6/0x4570 mm/huge_memory.c:1286 wp_huge_pmd mm/memory.c:3873 [inline] __handle_mm_fault+0x22f5/0x4460 mm/memory.c:4086 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 RIP: 0010:copy_user_generic_unrolled+0x89/0xc0 arch/x86/lib/copy_user_64.S:66 Code: 38 4c 89 47 20 4c 89 4f 28 4c 89 57 30 4c 89 5f 38 48 8d 76 40 48 8d 7f 40 ff c9 75 b6 89 d1 83 e2 07 c1 e9 03 74 12 4c 8b 06 <4c> 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10 89 d1 8a RSP: 0018:ffff880199667a58 EFLAGS: 00010202 RAX: ffffed00332ccf60 RBX: 0000000000000020 RCX: 0000000000000004 RDX: 0000000000000000 RSI: ffff880199667ae0 RDI: 0000000020000400 RBP: ffff880199667a90 R08: 0000000000000013 R09: ffffed00332ccf5c R10: ffffed00332ccf5f R11: ffff880199667aff R12: 0000000020000420 R13: 0000000020000400 R14: ffff880199667ae0 R15: 00007ffffffff000 copy_to_user include/linux/uaccess.h:155 [inline] userfaultfd_read+0x17e/0x2c0 fs/userfaultfd.c:1194 __vfs_read+0x117/0xa80 fs/read_write.c:416 vfs_read+0x17f/0x3d0 fs/read_write.c:452 ksys_read+0x101/0x260 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a79 Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f9ae1e20c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f9ae1e216d4 RCX: 0000000000455a79 RDX: 0000000000000064 RSI: 0000000020000400 RDI: 0000000000000014 RBP: 000000000072bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004bffa5 R14: 00000000004d0d28 R15: 0000000000000001 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) ====================================================== WARNING: possible circular locking dependency detected 4.18.0-rc4+ #143 Not tainted ------------------------------------------------------ syz-executor5/18405 is trying to acquire lock: 00000000aa9e93e3 ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 but task is already holding lock: 000000005707f499 (&p->pi_lock){-.-.}, at: try_to_wake_up+0xd2/0x12b0 kernel/sched/core.c:1985 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&p->pi_lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 try_to_wake_up+0xd2/0x12b0 kernel/sched/core.c:1985 wake_up_process+0x10/0x20 kernel/sched/core.c:2148 __up.isra.1+0x1c0/0x2a0 kernel/locking/semaphore.c:262 up+0x13c/0x1c0 kernel/locking/semaphore.c:187 __up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:242 console_unlock+0x7a2/0x10b0 kernel/printk/printk.c:2411 vprintk_emit+0x6c6/0xdf0 kernel/printk/printk.c:1907 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382 printk+0xa7/0xcf kernel/printk/printk.c:1981 load_umh+0x51/0xbd net/bpfilter/bpfilter_kern.c:98 do_one_initcall+0x127/0x913 init/main.c:884 do_initcall_level init/main.c:952 [inline] do_initcalls init/main.c:960 [inline] do_basic_setup init/main.c:978 [inline] kernel_init_freeable+0x49b/0x58e init/main.c:1135 kernel_init+0x11/0x1b3 init/main.c:1061 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 -> #0 ((console_sem).lock){-.-.}: lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225 console_trylock+0x15/0xa0 kernel/printk/printk.c:2230 console_trylock_spinning kernel/printk/printk.c:1643 [inline] vprintk_emit+0x6ad/0xdf0 kernel/printk/printk.c:1906 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382 printk+0xa7/0xcf kernel/printk/printk.c:1981 kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:251 notifier_call_chain+0x180/0x390 kernel/notifier.c:93 __atomic_notifier_call_chain kernel/notifier.c:183 [inline] atomic_notifier_call_chain+0x98/0x190 kernel/notifier.c:193 notify_die+0x1be/0x2e0 kernel/notifier.c:549 do_general_protection+0x248/0x2f0 arch/x86/kernel/traps.c:559 general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1159 __delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:83 delayacct_blkio_end include/linux/delayacct.h:128 [inline] try_to_wake_up+0xacb/0x12b0 kernel/sched/core.c:2056 default_wake_function+0x30/0x50 kernel/sched/core.c:3739 autoremove_wake_function+0x80/0x370 kernel/sched/wait.c:373 wake_page_function+0x15f/0x1c0 mm/filemap.c:1010 __wake_up_common+0x191/0x740 kernel/sched/wait.c:90 __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165 wake_up_page_bit+0x2ab/0x5b0 mm/filemap.c:1030 unlock_page+0x223/0x2c0 mm/filemap.c:1207 do_huge_pmd_wp_page+0x13f6/0x4570 mm/huge_memory.c:1286 wp_huge_pmd mm/memory.c:3873 [inline] __handle_mm_fault+0x22f5/0x4460 mm/memory.c:4086 handle_mm_fault+0x53e/0xc80 mm/memory.c:4133 __do_page_fault+0x620/0xe50 arch/x86/mm/fault.c:1396 do_page_fault+0xf6/0x8c0 arch/x86/mm/fault.c:1471 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1160 copy_user_generic_unrolled+0x89/0xc0 arch/x86/lib/copy_user_64.S:66 copy_to_user include/linux/uaccess.h:155 [inline] userfaultfd_read+0x17e/0x2c0 fs/userfaultfd.c:1194 __vfs_read+0x117/0xa80 fs/read_write.c:416 vfs_read+0x17f/0x3d0 fs/read_write.c:452 ksys_read+0x101/0x260 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->pi_lock); lock((console_sem).lock); lock(&p->pi_lock); lock((console_sem).lock); *** DEADLOCK *** 5 locks held by syz-executor5/18405: #0: 00000000d3e3a148 (&mm->mmap_sem){++++}, at: __do_page_fault+0x389/0xe50 arch/x86/mm/fault.c:1325 #1: 000000003e093ab1 (&(ptlock_ptr(page))->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline] #1: 000000003e093ab1 (&(ptlock_ptr(page))->rlock){+.+.}, at: do_huge_pmd_wp_page+0xbbd/0x4570 mm/huge_memory.c:1254 #2: 00000000eab2d0f1 (&page_wait_table[i]){-.-.}, at: wake_up_page_bit+0x291/0x5b0 mm/filemap.c:1029 #3: 000000005707f499 (&p->pi_lock){-.-.}, at: try_to_wake_up+0xd2/0x12b0 kernel/sched/core.c:1985 #4: 00000000a2153946 (rcu_read_lock){....}, at: atomic_notifier_call_chain+0x0/0x190 kernel/notifier.c:329 stack backtrace: CPU: 1 PID: 18405 Comm: syz-executor5 Not tainted 4.18.0-rc4+ #143 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 print_circular_bug.isra.36.cold.57+0x1bd/0x27d kernel/locking/lockdep.c:1227 check_prev_add kernel/locking/lockdep.c:1867 [inline] check_prevs_add kernel/locking/lockdep.c:1980 [inline] validate_chain kernel/locking/lockdep.c:2421 [inline] __lock_acquire+0x3449/0x5020 kernel/locking/lockdep.c:3435 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225 console_trylock+0x15/0xa0 kernel/printk/printk.c:2230 console_trylock_spinning kernel/printk/printk.c:1643 [inline] vprintk_emit+0x6ad/0xdf0 kernel/printk/printk.c:1906 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382 printk+0xa7/0xcf kernel/printk/printk.c:1981 kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:251 notifier_call_chain+0x180/0x390 kernel/notifier.c:93 __atomic_notifier_call_chain kernel/notifier.c:183 [inline] atomic_notifier_call_chain+0x98/0x190 kernel/notifier.c:193 notify_die+0x1be/0x2e0 kernel/notifier.c:549 do_general_protection+0x248/0x2f0 arch/x86/kernel/traps.c:559 general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1159 RIP: 0010:__delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:83 Code: 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 48 8b 9b 48 12 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 38 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 51 44 8b 63 38 31 ff 41 83 e4 01 RSP: 0018:ffff880199666688 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90007437000 RDX: 0000000000000007 RSI: ffffffff817d1c51 RDI: 0000000000000038 RBP: ffff8801996666a0 R08: ffffed003b5e46d7 R09: 0000000000000000 R10: ffff8801996667b0 R11: ffff8801daf236b3 R12: ffff8801d86b4340 R13: ffff8801986bc040 R14: ffff8801986bc07c R15: 0000000000000002 delayacct_blkio_end include/linux/delayacct.h:128 [inline] try_to_wake_up+0xacb/0x12b0 kernel/sched/core.c:2056 default_wake_function+0x30/0x50 kernel/sched/core.c:3739 autoremove_wake_function+0x80/0x370 kernel/sched/wait.c:373 wake_page_function+0x15f/0x1c0 mm/filemap.c:1010 __wake_up_common+0x191/0x740 kernel/sched/wait.c:90 __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165 wake_up_page_bit+0x2ab/0x5b0 mm/filemap.c:1030 unlock_page+0x223/0x2c0 mm/filemap.c:1207 do_huge_pmd_wp_page+0x13f6/0x4570 mm/huge_memory.c:1286 Lost 199 message(s)! ---[ end trace b4691e87c92d78a5 ]--- RIP: 0010:__delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:83 Code: 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 48 8b 9b 48 12 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 38 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 51 44 8b 63 38 31 ff 41 83 e4 01 RSP: 0018:ffff880199666688 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90007437000 RDX: 0000000000000007 RSI: ffffffff817d1c51 RDI: 0000000000000038 RBP: ffff8801996666a0 R08: ffffed003b5e46d7 R09: 0000000000000000 R10: ffff8801996667b0 R11: ffff8801daf236b3 R12: ffff8801d86b4340 R13: ffff8801986bc040 R14: ffff8801986bc07c R15: 0000000000000002 FS: 00007f9ae1e21700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ae1e41c88 CR3: 00000001d96b4000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400