bisecting fixing commit since c3038e718a19fc596f7b1baba0f83d5146dc7784 building syzkaller on 25bb509e5964da8203766c4039e4fef25e4689b1 testing commit c3038e718a19fc596f7b1baba0f83d5146dc7784 with gcc (GCC) 8.1.0 kernel signature: 07570945f8508b1fe694978a583da2b2c5fb5f1a run #0: crashed: INFO: task hung in genl_rcv_msg run #1: crashed: INFO: task hung in genl_rcv_msg run #2: crashed: INFO: task hung in genl_rcv_msg run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing current HEAD db5b9190ff8202b609fe802ccde41cb28669389f testing commit db5b9190ff8202b609fe802ccde41cb28669389f with gcc (GCC) 8.1.0 kernel signature: 58f545bba0eb0f174a445aea3a2c3939787e25ae run #0: crashed: INFO: task hung in genl_rcv_msg run #1: crashed: INFO: task hung in genl_rcv_msg run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 38m30.166213901s (build: 17m49.963077231s, test: 20m6.727793564s) the crash still happens on HEAD commit msg: Linux 4.19.96 crash: INFO: task hung in genl_rcv_msg INFO: task syz-executor.1:13684 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28424 13684 7194 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f263ab639c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f263ab63a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f263ab63a00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f263ab63a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.1:13695 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27720 13695 7194 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f263ab429c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f263ab42a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f263ab42a00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f263ab42a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.3:13687 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D26536 13687 7186 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f66476ff9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f66476ffa58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f66476ffa00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f66476ffa40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.3:13690 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28424 13690 7186 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f39 Code: Bad RIP value. RSP: 002b:00007f66476dec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39 RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000004 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f66476df6d4 R13: 00000000004cf980 R14: 00000000004de090 R15: 00000000ffffffff INFO: task syz-executor.2:13689 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28424 13689 7190 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f4e933569c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f4e93356a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f4e93356a00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f4e93356a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.2:13698 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27720 13698 7190 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f4e933359c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f4e93335a58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f4e93335a00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f4e93335a40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.4:13694 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28424 13694 7188 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f5688eed9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5688eeda58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f5688eeda00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f5688eeda40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.4:13699 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27720 13699 7188 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f5688ecc9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5688ecca58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f5688ecca00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f5688ecca40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.0:13697 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28424 13697 7196 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f9cc1c1d9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9cc1c1da58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f9cc1c1da00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000293 R12: 00007f9cc1c1da40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff INFO: task syz-executor.0:13700 blocked for more than 140 seconds. Not tainted 4.19.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27720 13700 7196 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x806/0x1210 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413bf1 Code: f8 ff 89 c3 66 41 89 84 24 c8 00 00 00 75 86 66 2e 0f 1f 84 00 00 00 00 00 ba 29 f8 ff ff eb 95 66 0f 1f 84 00 00 00 00 00 e8 73 ff ff 8b 18 ba 00 04 00 00 48 89 e6 48 89 c5 89 df e8 c7 c8 RSP: 002b:00007f9cc1bfc9c0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9cc1bfca58 RCX: 0000000000413bf1 RDX: 0000000000000000 RSI: 00007f9cc1bfca00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 000000000000000b R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f9cc1bfca40 R13: 00000000004d17d0 R14: 00000000004e0b68 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 00000000452db395 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/6946: #0: 0000000003537d6a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:767 2 locks held by getty/7068: #0: 000000006fcfe25a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000001377054 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7069: #0: 000000008c96ebb9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a3ef8133 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7070: #0: 000000006a38fc68 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000b78c2806 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7071: #0: 000000004938c458 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000006bc95bd1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7072: #0: 000000005c009a4b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003e94a28a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7073: #0: 00000000dabc7b4a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000068a2a778 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/7074: #0: 00000000ac071f08 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000005032086b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 3 locks held by syz-executor.5/13679: 2 locks held by syz-executor.1/13684: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.1/13695: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.3/13687: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.3/13690: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.2/13689: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.2/13698: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.4/13694: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.4/13699: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.0/13697: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.0/13700: #0: 000000004a1f8dec (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 00000000abb28573 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1041 Comm: khungtaskd Not tainted 4.19.96-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+0x123/0x177 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.4+0x3e/0x76 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xe6/0x11a 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+0x324/0x3e0 kernel/kthread.c:246 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: 13679 Comm: syz-executor.5 Not tainted 4.19.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lock_is_held_type+0x141/0x210 kernel/locking/lockdep.c:3942 Code: ff 65 4c 8b 24 25 40 ee 01 00 49 8d bc 24 7c 08 00 00 41 89 c5 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 <48> 89 fa 83 e2 07 83 c2 03 38 c2 7c 04 84 c0 75 76 48 c7 c7 48 07 RSP: 0018:ffff88808cedec98 EFLAGS: 00000803 RAX: 0000000000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffff1101243e54f RSI: ffffffff87f98320 RDI: ffff8880921f2a7c RBP: ffff88808cedecb8 R08: ffffed1015d44733 R09: ffffed1015d44732 R10: ffffed1015d44732 R11: ffff8880aea23993 R12: ffff8880921f2200 R13: 0000000000000001 R14: 0000000000000000 R15: 000000000000009a FS: 00007fbd58923700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000752000 CR3: 000000009f2c7000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:344 [inline] rcu_read_lock_held+0xa9/0xc0 kernel/rcu/update.c:287 __rhashtable_lookup include/linux/rhashtable.h:492 [inline] rhashtable_lookup include/linux/rhashtable.h:516 [inline] rhashtable_lookup_fast include/linux/rhashtable.h:542 [inline] tipc_sk_lookup+0x838/0x950 net/tipc/socket.c:2727 tipc_nl_publ_dump+0x1bf/0xcce net/tipc/socket.c:3531 __tipc_nl_compat_dumpit.isra.11+0x1e0/0x960 net/tipc/netlink_compat.c:207 tipc_nl_compat_publ_dump net/tipc/netlink_compat.c:1008 [inline] tipc_nl_compat_sk_dump+0x4ea/0x990 net/tipc/netlink_compat.c:1059 __tipc_nl_compat_dumpit.isra.11+0x2b0/0x960 net/tipc/netlink_compat.c:216 tipc_nl_compat_dumpit+0x1e3/0x4c0 net/tipc/netlink_compat.c:288 tipc_nl_compat_handle net/tipc/netlink_compat.c:1233 [inline] tipc_nl_compat_recv+0x460/0xa70 net/tipc/netlink_compat.c:1296 genl_family_rcv_msg+0x591/0xe80 net/netlink/genetlink.c:602 genl_rcv_msg+0xa7/0x140 net/netlink/genetlink.c:627 netlink_rcv_skb+0x142/0x390 net/netlink/af_netlink.c:2454 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x445/0x640 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x765/0xc50 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459f39 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fbd58922c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459f39 RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000004 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbd589236d4 R13: 00000000004cf980 R14: 00000000004de090 R15: 00000000ffffffff