bisecting fixing commit since f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7 testing commit f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 7e46026250e86cd0a078ebdf123c89476cd384cbd29c481f15693cb6522f5942 all runs: crashed: INFO: task hung in rtnl_lock testing current HEAD 4938296e03bd227e5020d63d418956fe52baf97c testing commit 4938296e03bd227e5020d63d418956fe52baf97c compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 353347b6e8113f516621f67f73deb635248e25a7aa334de152a3f154ca018476 all runs: crashed: INFO: task hung in rtnl_lock revisions tested: 2, total time: 40m11.589512135s (build: 24m55.010215692s, test: 14m46.784787317s) the crash still happens on HEAD commit msg: Linux 4.19.198 crash: INFO: task hung in rtnl_lock Bluetooth: hci4: command 0x0406 tx timeout Bluetooth: hci3: command 0x0406 tx timeout Bluetooth: hci0: command 0x0406 tx timeout Bluetooth: hci2: command 0x0406 tx timeout Bluetooth: hci1: command 0x0406 tx timeout INFO: task kworker/0:1:14 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:1 D24312 14 2 0x80000000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 reg_check_chans_work+0x73/0xb20 net/wireless/reg.c:2189 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/1:3:3410 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D24424 3410 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3989 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.2:5898 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D23432 5898 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 __sys_sendto+0x1f2/0x2e0 net/socket.c:1897 __do_sys_sendto net/socket.c:1909 [inline] __se_sys_sendto net/socket.c:1905 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1905 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41832c Code: Bad RIP value. RSP: 002b:00007ffd6814fc00 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001493720 RCX: 000000000041832c RDX: 0000000000000020 RSI: 0000000001493770 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffd6814fc44 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001493770 INFO: task syz-executor.5:5900 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D23768 5900 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 __sys_sendto+0x1f2/0x2e0 net/socket.c:1897 __do_sys_sendto net/socket.c:1909 [inline] __se_sys_sendto net/socket.c:1905 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1905 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41832c Code: Bad RIP value. RSP: 002b:00007ffce553fab0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001493720 RCX: 000000000041832c RDX: 0000000000000028 RSI: 0000000001493770 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffce553faf4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001493770 INFO: task syz-executor.0:5902 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D23816 5902 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 __sys_sendto+0x1f2/0x2e0 net/socket.c:1897 __do_sys_sendto net/socket.c:1909 [inline] __se_sys_sendto net/socket.c:1905 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1905 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41832c Code: Bad RIP value. RSP: 002b:00007ffd8fbe1860 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001493720 RCX: 000000000041832c RDX: 0000000000000028 RSI: 0000000001493770 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffd8fbe18a4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001493770 INFO: task syz-executor.1:5906 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D23752 5906 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 __sys_sendto+0x1f2/0x2e0 net/socket.c:1897 __do_sys_sendto net/socket.c:1909 [inline] __se_sys_sendto net/socket.c:1905 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1905 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41832c Code: Bad RIP value. RSP: 002b:00007ffebed12000 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001493720 RCX: 000000000041832c RDX: 0000000000000028 RSI: 0000000001493770 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffebed12044 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001493770 INFO: task syz-executor.3:5907 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D23560 5907 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 __sys_sendto+0x1f2/0x2e0 net/socket.c:1897 __do_sys_sendto net/socket.c:1909 [inline] __se_sys_sendto net/socket.c:1905 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1905 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41832c Code: Bad RIP value. RSP: 002b:00007fff55d0a3e0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001493720 RCX: 000000000041832c RDX: 0000000000000028 RSI: 0000000001493770 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fff55d0a424 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001493770 INFO: task kworker/0:3:6801 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:3 D26680 6801 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3989 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.4:7208 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D25064 7208 5905 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 load_metaops_and_vet net/sched/act_ife.c:281 [inline] populate_metalist net/sched/act_ife.c:456 [inline] tcf_ife_init+0xfb5/0x1590 net/sched/act_ife.c:580 tcf_action_init_1+0x8c6/0xbc0 net/sched/act_api.c:870 tcf_action_init+0x178/0x300 net/sched/act_api.c:936 tcf_action_add+0xf2/0x320 net/sched/act_api.c:1317 tc_ctl_action+0x28d/0x3d0 net/sched/act_api.c:1372 rtnetlink_rcv_msg+0x34f/0x950 net/core/rtnetlink.c:4782 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 ___sys_sendmsg+0x647/0x950 net/socket.c:2225 __sys_sendmsg+0xd9/0x180 net/socket.c:2263 __do_sys_sendmsg net/socket.c:2272 [inline] __se_sys_sendmsg net/socket.c:2270 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2270 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f615ff21188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055cf00 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cf00 R13: 00007ffc68f7bf6f R14: 00007f615ff21300 R15: 0000000000022000 INFO: task syz-executor.4:7219 blocked for more than 140 seconds. Not tainted 4.19.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28392 7219 5905 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2457 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4800 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1911 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:661 ___sys_sendmsg+0x647/0x950 net/socket.c:2225 __sys_sendmsg+0xd9/0x180 net/socket.c:2263 __do_sys_sendmsg net/socket.c:2272 [inline] __se_sys_sendmsg net/socket.c:2270 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2270 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f615fedf188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055d040 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055d040 R13: 00007ffc68f7bf6f R14: 00007f615fedf300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/0:1/14: #0: 00000000c023f067 ((wq_completion)"events_power_efficient"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2124 #1: 00000000d1c8ab14 ((reg_check_chans).work){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2128 #2: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by khungtaskd/1087: #0: 00000000e66e4861 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4443 3 locks held by kworker/1:3/3410: #0: 00000000a1123657 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2124 #1: 00000000d174aa60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2128 #2: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by in:imklog/5560: #0: 000000007c3db79c (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:767 1 lock held by syz-executor.2/5898: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 1 lock held by syz-executor.5/5900: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 1 lock held by syz-executor.0/5902: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 1 lock held by syz-executor.1/5906: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 1 lock held by syz-executor.3/5907: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 3 locks held by kworker/0:3/6801: #0: 00000000a1123657 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2124 #1: 000000001700de2f ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2128 #2: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.4/7208: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.4/7209: 1 lock held by syz-executor.4/7219: #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 0000000040d2e2ff (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4779 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1087 Comm: khungtaskd Not tainted 4.19.198-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+0x17c/0x226 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf5/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 4.19.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_release+0x47e/0x840 kernel/locking/lockdep.c:3931 Code: 00 00 00 fc ff df 48 c7 04 03 00 00 00 00 48 8b 45 d0 65 48 33 04 25 28 00 00 00 0f 85 1e 03 00 00 48 83 c4 78 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 65 8b 05 75 cd b6 7e 83 f8 3f 0f 87 59 02 00 00 RSP: 0018:ffff8881f56bfcf0 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffff8881e09f9e40 RCX: 1ffff1103ead6547 RDX: 1ffffffff10a3f71 RSI: 0000000000000003 RDI: 0000000000000286 RBP: ffff8881f56bfd00 R08: 0000000000000000 R09: ffffed103ed0473a R10: ffffed103ed0473a R11: ffff8881f68239d3 R12: ffff8881e7e52340 R13: 00000000000001ea R14: ffff8881f56b2a40 R15: ffff8881f56b21c0 FS: 0000000000000000(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d71e0406e8 CR3: 000000000846d005 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:681 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:423 [inline] batadv_nc_worker+0x191/0x630 net/batman-adv/network-coding.c:730 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415