loop0: detected capacity change from 0 to 1024 netlink: 36 bytes leftover after parsing attributes in process `syz.0.0'. netlink: 'syz.0.0': attribute type 10 has an invalid length. bond0: (slave netdevsim0): Enslaving as an active interface with an up link bond0: (slave netdevsim0): Releasing backup interface ============================================ WARNING: possible recursive locking detected 6.14.0-syzkaller-09352-g0c86b42439b6 #0 Not tainted -------------------------------------------- syz.0.0/5321 is trying to acquire lock: ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: dev_close+0x121/0x280 net/core/dev_api.c:224 but task is already holding lock: ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: do_setlink+0x209/0x4370 net/core/rtnetlink.c:3025 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev->lock); lock(&dev->lock); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz.0.0/5321: #0: ffffffff900e5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff900e5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff900e5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4061 #1: ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2751 [inline] #1: ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline] #1: ffff888042eccd28 (&dev->lock){+.+.}-{4:4}, at: do_setlink+0x209/0x4370 net/core/rtnetlink.c:3025 stack backtrace: CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted 6.14.0-syzkaller-09352-g0c86b42439b6 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042 check_deadlock kernel/locking/lockdep.c:3094 [inline] validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 __mutex_lock_common kernel/locking/mutex.c:587 [inline] __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:732 netdev_lock include/linux/netdevice.h:2751 [inline] netdev_lock_ops include/net/netdev_lock.h:42 [inline] dev_close+0x121/0x280 net/core/dev_api.c:224 __bond_release_one+0xcaf/0x1220 drivers/net/bonding/bond_main.c:2629 bond_slave_netdev_event drivers/net/bonding/bond_main.c:4028 [inline] bond_netdev_event+0x557/0xfb0 drivers/net/bonding/bond_main.c:4146 notifier_call_chain+0x1a5/0x3f0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2218 [inline] call_netdevice_notifiers net/core/dev.c:2232 [inline] netif_change_net_namespace+0xa30/0x1c20 net/core/dev.c:12163 do_setlink+0x3aa/0x4370 net/core/rtnetlink.c:3042 rtnl_changelink net/core/rtnetlink.c:3766 [inline] __rtnl_newlink net/core/rtnetlink.c:3925 [inline] rtnl_newlink+0x17e2/0x1fe0 net/core/rtnetlink.c:4062 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6952 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8e8/0xce0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:727 ____sys_sendmsg+0x53c/0x870 net/socket.c:2566 ___sys_sendmsg net/socket.c:2620 [inline] __sys_sendmsg+0x271/0x360 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb17b38d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb17c2be038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb17b5a5fa0 RCX: 00007fb17b38d169 RDX: 0000000000000000 RSI: 0000200000000340 RDI: 0000000000000008 RBP: 00007fb17b40e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb17b5a5fa0 R15: 00007fff2d1aa5d8