Hello, syzbot found the following crash on: HEAD commit: 6132c1d9 net: core: devlink.c: Hold devlink->lock from the.. git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=16978909e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=3b8906eb6a7d6028 dashboard link: https://syzkaller.appspot.com/bug?extid=55de90ab5f44172b0c90 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12808281e00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=134ca6fde00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+55de90ab5f44172b0c90@xxxxxxxxxxxxxxxxxxxxxxxxx iwpm_register_pid: Unable to send a nlmsg (client = 2) infiniband syz1: RDMA CMA: cma_listen_on_dev, error -98 netlink: 'syz-executor639': attribute type 1 has an invalid length. 8021q: adding VLAN 0 to HW filter on device bond1 bond1: (slave gretap1): making interface the new active one ====================================================== WARNING: possible circular locking dependency detected 5.6.0-rc2-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor639/9689 is trying to acquire lock: ffffffff8a5d2a60 (lock#3){+.+.}, at: cma_netdev_callback+0xc6/0x380 drivers/infiniband/core/cma.c:4605 but task is already holding lock: ffffffff8a74da00 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] ffffffff8a74da00 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x405/0xaf0 net/core/rtnetlink.c:5433 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x156/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 siw_create_listen+0x329/0xed0 drivers/infiniband/sw/siw/siw_cm.c:1951 iw_cm_listen+0x16e/0x1f0 drivers/infiniband/core/iwcm.c:582 cma_iw_listen drivers/infiniband/core/cma.c:2450 [inline] rdma_listen+0x613/0x970 drivers/infiniband/core/cma.c:3614 cma_listen_on_dev+0x530/0x6a0 drivers/infiniband/core/cma.c:2501 cma_add_one+0x6fe/0xbf0 drivers/infiniband/core/cma.c:4666 add_client_context+0x3dd/0x550 drivers/infiniband/core/device.c:681 enable_device_and_get+0x1df/0x3c0 drivers/infiniband/core/device.c:1316 ib_register_device drivers/infiniband/core/device.c:1382 [inline] ib_register_device+0xa89/0xe40 drivers/infiniband/core/device.c:1343 siw_device_register drivers/infiniband/sw/siw/siw_main.c:70 [inline] siw_newlink drivers/infiniband/sw/siw/siw_main.c:565 [inline] siw_newlink+0xdef/0x1310 drivers/infiniband/sw/siw/siw_main.c:542 nldev_newlink+0x28a/0x430 drivers/infiniband/core/nldev.c:1538 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x5d9/0x980 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (lock#3){+.+.}: check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x156/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 cma_netdev_callback+0xc6/0x380 drivers/infiniband/core/cma.c:4605 notifier_call_chain+0xc2/0x230 kernel/notifier.c:83 __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:368 call_netdevice_notifiers_info net/core/dev.c:1948 [inline] call_netdevice_notifiers_info+0xba/0x130 net/core/dev.c:1933 call_netdevice_notifiers_extack net/core/dev.c:1960 [inline] call_netdevice_notifiers+0x79/0xa0 net/core/dev.c:1974 bond_change_active_slave+0x185b/0x2050 drivers/net/bonding/bond_main.c:944 bond_select_active_slave+0x276/0xae0 drivers/net/bonding/bond_main.c:986 bond_enslave+0x44ef/0x4af0 drivers/net/bonding/bond_main.c:1823 do_set_master net/core/rtnetlink.c:2468 [inline] do_set_master+0x1dd/0x240 net/core/rtnetlink.c:2441 __rtnl_newlink+0x13a3/0x1790 net/core/rtnetlink.c:3346 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3377 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5436 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2478 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5454 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(lock#3); lock(rtnl_mutex); lock(lock#3); *** DEADLOCK *** 1 lock held by syz-executor639/9689: #0: ffffffff8a74da00 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8a74da00 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x405/0xaf0 net/core/rtnetlink.c:5433 stack backtrace: CPU: 0 PID: 9689 Comm: syz-executor639 Not tainted 5.6.0-rc2-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 print_circular_bug.isra.0.cold+0x163/0x172 kernel/locking/lockdep.c:1684 check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1808 check_prev_add kernel/locking/lockdep.c:2475 [inline] check_prevs_add kernel/locking/lockdep.c:2580 [inline] validate_chain kernel/locking/lockdep.c:2970 [inline] __lock_acquire+0x2596/0x4a00 kernel/locking/lockdep.c:3954 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x156/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 cma_netdev_callback+0xc6/0x380 drivers/infiniband/core/cma.c:4605 notifier_call_chain+0xc2/0x230 kernel/notifier.c:83 __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:368 call_netdevice_notifiers_info net/core/dev.c:1948 [inline] call_netdevice_notifiers_info+0xba/0x130 net/core/dev.c:1933 call_netdevice_notifiers_extack net/core/dev.c:1960 [inline] call_netdevice_notifiers+0x79/0xa0 net/core/dev.c:1974 bond_change_active_slave+0x185b/0x2050 drivers/net/bonding/bond_main.c:944 bond_select_active_slave+0x276/0xae0 drivers/net/bonding/bond_main.c:986 bond_enslave+0x44ef/0x4af0 drivers/net/bonding/bond_main.c:1823 do_set_master net/core/rtnetlink.c:2468 [inline] do_set_master+0x1dd/0x240 net/core/rtnetlink.c:2441 __rtnl_newlink+0x13a3/0x1790 net/core/rtnetlink.c:3346 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3377 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5436 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2478 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5454 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440509 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff80af47a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440509 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401d90 R13: 0000000000401e20 R14: 0000000000000000 R15: 0000000000000000 --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches
