RDX: 000000000000ff2e RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f722ba9d1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe93fd300f R14: 00007f722ba9d300 R15: 0000000000022000 ====================================================== WARNING: possible circular locking dependency detected 4.14.232-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/18744 is trying to acquire lock: (console_owner){-.-.}, at: [] console_trylock_spinning kernel/printk/printk.c:1658 [inline] (console_owner){-.-.}, at: [] vprintk_emit+0x32a/0x620 kernel/printk/printk.c:1922 but task is already holding lock: (&(&port->lock)->rlock){-.-.}, at: [] pty_write+0xdb/0x1d0 drivers/tty/pty.c:120 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&(&port->lock)->rlock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 tty_port_tty_get+0x1d/0x80 drivers/tty/tty_port.c:288 tty_port_default_wakeup+0x11/0x40 drivers/tty/tty_port.c:46 serial8250_tx_chars+0x3fe/0xbf0 drivers/tty/serial/8250/8250_port.c:1810 __start_tx drivers/tty/serial/8250/8250_port.c:1571 [inline] serial8250_start_tx+0x63c/0xa20 drivers/tty/serial/8250/8250_port.c:1649 __uart_start.isra.0+0x15f/0x1b0 drivers/tty/serial/serial_core.c:137 uart_write+0x2c4/0x560 drivers/tty/serial/serial_core.c:624 do_output_char+0x4f5/0x750 drivers/tty/n_tty.c:447 process_output drivers/tty/n_tty.c:514 [inline] n_tty_write+0x3e3/0xda0 drivers/tty/n_tty.c:2345 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x410/0x740 drivers/tty/tty_io.c:1043 redirected_tty_write+0x9c/0xb0 drivers/tty/tty_io.c:1064 do_loop_readv_writev fs/read_write.c:698 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_write+0x3da/0x550 fs/read_write.c:956 vfs_writev+0x125/0x290 fs/read_write.c:999 do_writev+0xfc/0x2c0 fs/read_write.c:1034 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #1 (&port_lock_key){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 serial8250_console_write+0x7a7/0x9d0 drivers/tty/serial/8250/8250_port.c:3253 call_console_drivers kernel/printk/printk.c:1725 [inline] console_unlock+0x99d/0xf20 kernel/printk/printk.c:2400 vprintk_emit+0x224/0x620 kernel/printk/printk.c:1923 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1996 register_console+0x6f4/0xad0 kernel/printk/printk.c:2719 univ8250_console_init+0x2f/0x3a drivers/tty/serial/8250/8250_core.c:691 console_init+0x46/0x53 kernel/printk/printk.c:2800 start_kernel+0x52e/0x770 init/main.c:634 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240 -> #0 (console_owner){-.-.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 console_trylock_spinning kernel/printk/printk.c:1679 [inline] vprintk_emit+0x367/0x620 kernel/printk/printk.c:1922 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x6d/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312 tty_insert_flip_string include/linux/tty_flip.h:37 [inline] pty_write+0x10d/0x1d0 drivers/tty/pty.c:122 n_tty_write+0x85e/0xda0 drivers/tty/n_tty.c:2356 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x410/0x740 drivers/tty/tty_io.c:1043 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb other info that might help us debug this: Chain exists of: console_owner --> &port_lock_key --> &(&port->lock)->rlock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&port->lock)->rlock); lock(&port_lock_key); lock(&(&port->lock)->rlock); lock(console_owner); *** DEADLOCK *** 5 locks held by syz-executor.5/18744: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write_lock drivers/tty/tty_io.c:885 [inline] #1: (&tty->atomic_write_lock){+.+.}, at: [] do_tty_write drivers/tty/tty_io.c:908 [inline] #1: (&tty->atomic_write_lock){+.+.}, at: [] tty_write+0x22d/0x740 drivers/tty/tty_io.c:1043 #2: (&tty->termios_rwsem){++++}, at: [] n_tty_write+0x18a/0xda0 drivers/tty/n_tty.c:2316 #3: (&ldata->output_lock){+.+.}, at: [] n_tty_write+0x82b/0xda0 drivers/tty/n_tty.c:2355 #4: (&(&port->lock)->rlock){-.-.}, at: [] pty_write+0xdb/0x1d0 drivers/tty/pty.c:120 stack backtrace: CPU: 0 PID: 18744 Comm: syz-executor.5 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 console_trylock_spinning kernel/printk/printk.c:1679 [inline] vprintk_emit+0x367/0x620 kernel/printk/printk.c:1922 vprintk_func+0x58/0x160 kernel/printk/printk_safe.c:409 printk+0x9e/0xbc kernel/printk/printk.c:1996 fail_dump lib/fault-inject.c:44 [inline] should_fail.cold+0xdf/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x6d/0x400 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] tty_buffer_alloc+0xc0/0x270 drivers/tty/tty_buffer.c:169 __tty_buffer_request_room+0x12c/0x290 drivers/tty/tty_buffer.c:267 tty_insert_flip_string_fixed_flag+0x8b/0x210 drivers/tty/tty_buffer.c:312 tty_insert_flip_string include/linux/tty_flip.h:37 [inline] pty_write+0x10d/0x1d0 drivers/tty/pty.c:122 n_tty_write+0x85e/0xda0 drivers/tty/n_tty.c:2356 do_tty_write drivers/tty/tty_io.c:959 [inline] tty_write+0x410/0x740 drivers/tty/tty_io.c:1043 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007f722ba9d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 000000000000ff2e RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f722ba9d1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe93fd300f R14: 00007f722ba9d300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 IPVS: length: 188 != 8 IPVS: length: 188 != 8 CPU: 1 PID: 18763 Comm: syz-executor.2 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc_node mm/slab.c:3297 [inline] kmem_cache_alloc_node_trace+0x25a/0x400 mm/slab.c:3659 __do_kmalloc_node mm/slab.c:3681 [inline] __kmalloc_node_track_caller+0x38/0x70 mm/slab.c:3696 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x96/0x510 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:980 [inline] alloc_skb_with_frags+0x85/0x500 net/core/skbuff.c:5255 sock_alloc_send_pskb+0x577/0x6d0 net/core/sock.c:2083 packet_alloc_skb net/packet/af_packet.c:2874 [inline] packet_snd+0x4f3/0x2470 net/packet/af_packet.c:2969 packet_sendmsg+0x11ad/0x2d70 net/packet/af_packet.c:3049 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1c7/0x2c0 net/socket.c:1731 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007fa26816d188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000000000a6 RSI: 00000000200003c0 RDI: 0000000000000005 RBP: 00007fa26816d1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe35556b0f R14: 00007fa26816d300 R15: 0000000000022000 IPVS: length: 188 != 2398895008 IPVS: length: 188 != 8 IPVS: length: 188 != 2398895008 IPVS: length: 188 != 2398895008 IPVS: length: 188 != 8 IPVS: length: 188 != 8 ip_tables: iptables: counters copy to user failed while replacing table IPVS: length: 168 != 8 IPVS: length: 186 != 8 IPVS: length: 188 != 2398895008 IPVS: length: 188 != 8 IPVS: length: 188 != 8 ip_tables: iptables: counters copy to user failed while replacing table kauditd_printk_skb: 7 callbacks suppressed audit: type=1804 audit(1620788813.113:86): pid=18941 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.2" name="/root/syzkaller-testdir900278040/syzkaller.saBux1/389/file0" dev="sda1" ino=14821 res=1 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 198 != 8 IPVS: length: 198 != 8 IPVS: length: 188 != 1182634784 IPVS: length: 188 != 1182634784 IPVS: length: 188 != 8 IPVS: length: 188 != 186376 IPVS: length: 188 != 186376 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 Dev loop4: unable to read RDB block 1 loop4: unable to read partition table loop4: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop4 () failed (rc=-5) Dev loop4: unable to read RDB block 1 loop4: unable to read partition table loop4: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop4 () failed (rc=-5) Dev loop4: unable to read RDB block 1 loop4: unable to read partition table loop4: partition table beyond EOD, truncated IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 133 != 8 IPVS: length: 178 != 8 IPVS: length: 178 != 8 IPVS: length: 179 != 8 IPVS: length: 188 != 2950900408 IPVS: length: 188 != 8 IPVS: length: 188 != 2398895008 netlink: 912 bytes leftover after parsing attributes in process `syz-executor.2'. audit: type=1804 audit(1620788818.053:87): pid=19496 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.2" name="/root/syzkaller-testdir900278040/syzkaller.saBux1/406/file0" dev="sda1" ino=14886 res=1 audit: type=1804 audit(1620788818.093:88): pid=19503 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.2" name="/root/syzkaller-testdir900278040/syzkaller.saBux1/406/file0" dev="sda1" ino=14886 res=1 IPVS: length: 188 != 8 IPVS: length: 188 != 2950900408 IPVS: length: 188 != 8 IPVS: length: 188 != 1182634784 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 IPVS: length: 188 != 8 capability: warning: `syz-executor.1' uses deprecated v2 capabilities in a way that may be insecure IPVS: length: 188 != 8 IPVS: length: 188 != 8