FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) ====================================================== WARNING: possible circular locking dependency detected 4.14.292-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/13445 is trying to acquire lock: (&(&gsm->tx_lock)->rlock){-...}, at: [] gsmld_write_wakeup+0x4e/0xd0 drivers/tty/n_gsm.c:2490 but task is already holding lock: (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x330 drivers/tty/serial/8250/8250_port.c:1891 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #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 uart_write_room+0xd5/0x340 drivers/tty/serial/serial_core.c:643 tty_write_room+0x61/0x80 drivers/tty/tty_ioctl.c:78 gsmld_write+0x69/0x120 drivers/tty/n_gsm.c:2546 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 __kernel_write+0xf5/0x330 fs/read_write.c:501 write_pipe_buf+0x143/0x1c0 fs/splice.c:797 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x326/0x7a0 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] default_file_splice_write+0xc5/0x150 fs/splice.c:809 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1016 splice_direct_to_actor+0x25a/0x700 fs/splice.c:971 do_splice_direct+0x164/0x210 fs/splice.c:1059 do_sendfile+0x47f/0xb30 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0xff/0x110 fs/read_write.c:1488 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&(&gsm->tx_lock)->rlock){-...}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 gsmld_write_wakeup+0x4e/0xd0 drivers/tty/n_gsm.c:2490 tty_wakeup+0xc3/0xf0 drivers/tty/tty_io.c:533 tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:49 serial8250_tx_chars+0x3fe/0xc70 drivers/tty/serial/8250/8250_port.c:1828 serial8250_handle_irq.part.0+0x28d/0x330 drivers/tty/serial/8250/8250_port.c:1915 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1888 [inline] serial8250_default_handle_irq+0x8a/0x1f0 drivers/tty/serial/8250/8250_port.c:1931 serial8250_interrupt+0xf3/0x210 drivers/tty/serial/8250/8250_core.c:129 __handle_irq_event_percpu+0xee/0x7f0 kernel/irq/handle.c:147 handle_irq_event_percpu kernel/irq/handle.c:187 [inline] handle_irq_event+0xed/0x240 kernel/irq/handle.c:204 handle_edge_irq+0x224/0xc40 kernel/irq/chip.c:770 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x93/0x1d0 arch/x86/kernel/irq.c:230 ret_from_intr+0x0/0x1e __sanitizer_cov_trace_pc+0xe/0x50 kernel/kcov.c:65 fib6_walk_continue+0x41c/0x700 net/ipv6/ip6_fib.c:1696 fib6_walk+0x177/0x350 net/ipv6/ip6_fib.c:1749 fib6_clean_tree+0xc1/0xf0 net/ipv6/ip6_fib.c:1823 __fib6_clean_all+0xfd/0x230 net/ipv6/ip6_fib.c:1839 fib6_clean_all net/ipv6/ip6_fib.c:1850 [inline] fib6_run_gc+0xf4/0x270 net/ipv6/ip6_fib.c:1948 ndisc_netdev_event+0xa2/0x3f0 net/ipv6/ndisc.c:1761 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] dev_set_mac_address net/core/dev.c:6970 [inline] dev_set_mac_address+0x1e8/0x2d0 net/core/dev.c:6955 do_setlink+0xc58/0x2bf0 net/core/rtnetlink.c:2047 rtnl_newlink+0x1271/0x1830 net/core/rtnetlink.c:2662 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4322 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454 netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 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: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port_lock_key); lock(&(&gsm->tx_lock)->rlock); lock(&port_lock_key); lock(&(&gsm->tx_lock)->rlock); *** DEADLOCK *** 7 locks held by syz-executor.0/13445: #0: (rtnl_mutex){+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:72 [inline] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x31d/0xb10 net/core/rtnetlink.c:4317 #1: (&(&net->ipv6.fib6_gc_lock)->rlock){+...}, at: [] spin_trylock_bh include/linux/spinlock.h:377 [inline] #1: (&(&net->ipv6.fib6_gc_lock)->rlock){+...}, at: [] fib6_run_gc+0x1df/0x270 net/ipv6/ip6_fib.c:1940 #2: (rcu_read_lock){....}, at: [] __fib6_clean_all+0x0/0x230 net/ipv6/ip6_fib.c:1824 #3: (&tb->tb6_lock){++.-}, at: [] __fib6_clean_all+0xe6/0x230 net/ipv6/ip6_fib.c:1838 #4: (&(&i->lock)->rlock){-.-.}, at: [] spin_lock include/linux/spinlock.h:317 [inline] #4: (&(&i->lock)->rlock){-.-.}, at: [] serial8250_interrupt+0x3a/0x210 drivers/tty/serial/8250/8250_core.c:119 #5: (&port_lock_key){-.-.}, at: [] serial8250_handle_irq.part.0+0x20/0x330 drivers/tty/serial/8250/8250_port.c:1891 #6: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref+0x1b/0x80 drivers/tty/tty_ldisc.c:305 stack backtrace: CPU: 1 PID: 13445 Comm: syz-executor.0 Not tainted 4.14.292-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 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 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160 gsmld_write_wakeup+0x4e/0xd0 drivers/tty/n_gsm.c:2490 tty_wakeup+0xc3/0xf0 drivers/tty/tty_io.c:533 tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:49 serial8250_tx_chars+0x3fe/0xc70 drivers/tty/serial/8250/8250_port.c:1828 serial8250_handle_irq.part.0+0x28d/0x330 drivers/tty/serial/8250/8250_port.c:1915 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1888 [inline] serial8250_default_handle_irq+0x8a/0x1f0 drivers/tty/serial/8250/8250_port.c:1931 serial8250_interrupt+0xf3/0x210 drivers/tty/serial/8250/8250_core.c:129 __handle_irq_event_percpu+0xee/0x7f0 kernel/irq/handle.c:147 handle_irq_event_percpu kernel/irq/handle.c:187 [inline] handle_irq_event+0xed/0x240 kernel/irq/handle.c:204 handle_edge_irq+0x224/0xc40 kernel/irq/chip.c:770 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline] handle_irq+0x35/0x50 arch/x86/kernel/irq_64.c:87 do_IRQ+0x93/0x1d0 arch/x86/kernel/irq.c:230 common_interrupt+0x93/0x93 arch/x86/entry/entry_64.S:576 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:23 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xe/0x50 kernel/kcov.c:65 RSP: 0018:ffff888072446eb8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffc8 RAX: ffff8880956201c0 RBX: ffff888072446f80 RCX: ffffc90005bfe000 RDX: 0000000000006ac3 RSI: ffffffff86397b2c RDI: ffff888072446fb4 RBP: ffff888090343c80 R08: ffffffff8b9cc778 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000003 R14: ffff888072446fa8 R15: ffffed100e488df5 fib6_walk_continue+0x41c/0x700 net/ipv6/ip6_fib.c:1696 fib6_walk+0x177/0x350 net/ipv6/ip6_fib.c:1749 fib6_clean_tree+0xc1/0xf0 net/ipv6/ip6_fib.c:1823 __fib6_clean_all+0xfd/0x230 net/ipv6/ip6_fib.c:1839 fib6_clean_all net/ipv6/ip6_fib.c:1850 [inline] fib6_run_gc+0xf4/0x270 net/ipv6/ip6_fib.c:1948 ndisc_netdev_event+0xa2/0x3f0 net/ipv6/ndisc.c:1761 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] dev_set_mac_address net/core/dev.c:6970 [inline] dev_set_mac_address+0x1e8/0x2d0 net/core/dev.c:6955 do_setlink+0xc58/0x2bf0 net/core/rtnetlink.c:2047 rtnl_newlink+0x1271/0x1830 net/core/rtnetlink.c:2662 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4322 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2454 netlink_unicast_kernel net/netlink/af_netlink.c:1296 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1322 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f8d61b93279 RSP: 002b:00007f8d60508168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8d61ca5f80 RCX: 00007f8d61b93279 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007f8d61bed2e9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd64377bdf R14: 00007f8d60508300 R15: 0000000000022000 FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop1): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) mac80211_hwsim hwsim6 €Š²Ù¨LµFÙŠÌ: renamed from wlan1 mac80211_hwsim hwsim3 €Š²Ù¨LµFÙŠÌ: renamed from wlan1 EXT4-fs: Warning: mounting with data=journal disables delayed allocation and O_DIRECT support! EXT4-fs (loop4): feature flags set on rev 0 fs, running e2fsck is recommended EXT4-fs (loop4): couldn't mount as ext3 due to feature incompatibilities netlink: 23 bytes leftover after parsing attributes in process `syz-executor.3'. IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready lo: Invalid MTU -6 requested, hw min 0 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.3'. EXT4-fs (loop4): feature flags set on rev 0 fs, running e2fsck is recommended netlink: 23 bytes leftover after parsing attributes in process `syz-executor.3'. EXT4-fs (loop4): couldn't mount as ext3 due to feature incompatibilities IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready netlink: 23 bytes leftover after parsing attributes in process `syz-executor.2'. IPv6: ADDRCONF(NETDEV_UP): veth11: link is not ready EXT4-fs (loop4): feature flags set on rev 0 fs, running e2fsck is recommended netlink: 23 bytes leftover after parsing attributes in process `syz-executor.5'. EXT4-fs (loop4): couldn't mount as ext3 due to feature incompatibilities IPv6: ADDRCONF(NETDEV_UP): veth3: link is not ready netlink: 4 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.2'. EXT4-fs (loop4): feature flags set on rev 0 fs, running e2fsck is recommended lo: Invalid MTU -6 requested, hw min 0 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. EXT4-fs (loop4): couldn't mount as ext3 due to feature incompatibilities netlink: 23 bytes leftover after parsing attributes in process `syz-executor.3'. IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready netlink: 23 bytes leftover after parsing attributes in process `syz-executor.2'. IPv6: ADDRCONF(NETDEV_UP): veth11: link is not ready lo: Invalid MTU -6 requested, hw min 0 IPv6: ADDRCONF(NETDEV_UP): veth3: link is not ready lo: Invalid MTU -6 requested, hw min 0 lo: Invalid MTU -6 requested, hw min 0 IPv6: ADDRCONF(NETDEV_UP): veth9: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth11: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth3: link is not ready lo: Invalid MTU -6 requested, hw min 0 lo: Invalid MTU -6 requested, hw min 0 lo: Invalid MTU -6 requested, hw min 0 lo: Invalid MTU -6 requested, hw min 0 lo: Invalid MTU -6 requested, hw min 0 kauditd_printk_skb: 4 callbacks suppressed audit: type=1326 audit(1662550811.152:88): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=14468 comm="syz-executor.5" exe="/root/syz-executor.5" sig=31 arch=c000003e syscall=202 compat=0 ip=0x7f87516cd279 code=0x0 audit: type=1326 audit(1662550811.222:89): auid=4294967295 uid=0 gid=0 ses=4294967295 pid=14499 comm="syz-executor.5" exe="/root/syz-executor.5" sig=31 arch=c000003e syscall=202 compat=0 ip=0x7f87516cd279 code=0x0