netlink: 'syz-executor.1': attribute type 2 has an invalid length. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Not tainted ------------------------------------------------------ syz-executor.1/13382 is trying to acquire lock: ffff88802370c218 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88802370c218 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3841 [inline] ffff88802370c218 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x22f5/0x3d30 net/core/dev.c:4359 but task is already holding lock: ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4347 [inline] ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:341 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __netif_tx_lock include/linux/netdevice.h:4347 [inline] sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:341 __dev_xmit_skb net/core/dev.c:3807 [inline] __dev_queue_xmit+0x1a24/0x3d30 net/core/dev.c:4359 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK+0x9e/0x430 include/linux/netfilter.h:314 mld_sendpack+0x838/0xda0 net/ipv6/mcast.c:1818 mld_send_cr net/ipv6/mcast.c:2119 [inline] mld_ifc_work+0x7d6/0xd90 net/ipv6/mcast.c:2650 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __dev_xmit_skb net/core/dev.c:3841 [inline] __dev_queue_xmit+0x22f5/0x3d30 net/core/dev.c:4359 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509 ndisc_solicit+0x493/0x6a0 neigh_probe net/core/neighbour.c:1077 [inline] __neigh_event_send+0xec8/0x15a0 net/core/neighbour.c:1244 neigh_event_send_probe include/net/neighbour.h:466 [inline] neigh_event_send include/net/neighbour.h:472 [inline] neigh_resolve_output+0x1b5/0x740 net/core/neighbour.c:1549 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 ip6_send_skb+0x112/0x230 net/ipv6/ip6_output.c:1955 icmp6_send+0x15fc/0x2070 net/ipv6/icmp.c:624 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x3c/0x4f0 net/ipv6/route.c:2799 ip_tunnel_xmit+0x164f/0x2940 net/ipv4/ip_tunnel.c:863 __gre_xmit+0x1cf/0x260 net/ipv4/ip_gre.c:483 erspan_xmit+0xaba/0x1310 net/ipv4/ip_gre.c:742 __netdev_start_xmit include/linux/netdevice.h:4882 [inline] netdev_start_xmit include/linux/netdevice.h:4896 [inline] xmit_one net/core/dev.c:3578 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3594 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:343 qdisc_restart net/sched/sch_generic.c:408 [inline] __qdisc_run+0xbfd/0x2170 net/sched/sch_generic.c:416 __dev_xmit_skb net/core/dev.c:3876 [inline] __dev_queue_xmit+0x14f0/0x3d30 net/core/dev.c:4359 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] rawv6_send_hdrinc+0xb79/0x1610 net/ipv6/raw.c:661 rawv6_sendmsg+0x1962/0x23c0 net/ipv6/raw.c:914 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&qdisc_xmit_lock_key#3); lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2); lock(&qdisc_xmit_lock_key#3); lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2); *** DEADLOCK *** 10 locks held by syz-executor.1/13382: #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rawv6_send_hdrinc+0x9df/0x1610 net/ipv6/raw.c:659 #1: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: ip6_finish_output2+0x712/0x1670 net/ipv6/ip6_output.c:122 #2: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #2: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:833 [inline] #2: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2d2/0x3d30 net/core/dev.c:4318 #3: ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #3: ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4347 [inline] #3: ffff88807b0fb0d8 (&qdisc_xmit_lock_key#3){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:341 #4: ffff88802a3481d8 (k-slock-AF_INET6){+.-.}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline] #4: ffff88802a3481d8 (k-slock-AF_INET6){+.-.}-{2:2}, at: icmpv6_xmit_lock net/ipv6/icmp.c:108 [inline] #4: ffff88802a3481d8 (k-slock-AF_INET6){+.-.}-{2:2}, at: icmp6_send+0xc45/0x2070 net/ipv6/icmp.c:545 #5: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #5: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: icmp6_send+0xba4/0x2070 net/ipv6/icmp.c:537 #6: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #6: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #6: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: ip6_finish_output2+0x712/0x1670 net/ipv6/ip6_output.c:122 #7: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #7: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #7: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: ip6_nd_hdr net/ipv6/ndisc.c:452 [inline] #7: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: ndisc_send_skb+0x572/0x1380 net/ipv6/ndisc.c:503 #8: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #8: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #8: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: ip6_finish_output2+0x712/0x1670 net/ipv6/ip6_output.c:122 #9: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #9: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:833 [inline] #9: ffffffff8e334000 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2d2/0x3d30 net/core/dev.c:4318 stack backtrace: CPU: 0 PID: 13382 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __dev_xmit_skb net/core/dev.c:3841 [inline] __dev_queue_xmit+0x22f5/0x3d30 net/core/dev.c:4359 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509 ndisc_solicit+0x493/0x6a0 neigh_probe net/core/neighbour.c:1077 [inline] __neigh_event_send+0xec8/0x15a0 net/core/neighbour.c:1244 neigh_event_send_probe include/net/neighbour.h:466 [inline] neigh_event_send include/net/neighbour.h:472 [inline] neigh_resolve_output+0x1b5/0x740 net/core/neighbour.c:1549 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 ip6_send_skb+0x112/0x230 net/ipv6/ip6_output.c:1955 icmp6_send+0x15fc/0x2070 net/ipv6/icmp.c:624 __icmpv6_send include/linux/icmpv6.h:28 [inline] icmpv6_send include/linux/icmpv6.h:49 [inline] ip6_link_failure+0x3c/0x4f0 net/ipv6/route.c:2799 ip_tunnel_xmit+0x164f/0x2940 net/ipv4/ip_tunnel.c:863 __gre_xmit+0x1cf/0x260 net/ipv4/ip_gre.c:483 erspan_xmit+0xaba/0x1310 net/ipv4/ip_gre.c:742 __netdev_start_xmit include/linux/netdevice.h:4882 [inline] netdev_start_xmit include/linux/netdevice.h:4896 [inline] xmit_one net/core/dev.c:3578 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3594 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:343 qdisc_restart net/sched/sch_generic.c:408 [inline] __qdisc_run+0xbfd/0x2170 net/sched/sch_generic.c:416 __dev_xmit_skb net/core/dev.c:3876 [inline] __dev_queue_xmit+0x14f0/0x3d30 net/core/dev.c:4359 neigh_output include/net/neighbour.h:542 [inline] ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137 ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222 NF_HOOK include/linux/netfilter.h:314 [inline] rawv6_send_hdrinc+0xb79/0x1610 net/ipv6/raw.c:661 rawv6_sendmsg+0x1962/0x23c0 net/ipv6/raw.c:914 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2585 ___sys_sendmsg net/socket.c:2639 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6aa887cf29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6aa95e00c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6aa89b3f80 RCX: 00007f6aa887cf29 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 000000000000000b RBP: 00007f6aa88ec074 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f6aa89b3f80 R15: 00007fff6e098228