INFO: task hung in rtnetlink_rcv

INFO: task hung in rtnetlink_rcv_msg
Status: upstream: reported C repro on 2019/02/22 17:00
Reported-by: syzbot+8218a8a0ff60c19b8eae@syzkaller.appspotmail.com
First crash: 894d, last: 10d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: INFO: task hung in addrconf_dad_work (log)
Repro: C syz .config

Fix bisection: the fix commit could be any of (bisect log):
  2618500dd370 arm: dts: mediatek: Update mt7629 dts to reflect the latest dt-binding
  c9b96eb6da2a Merge branch 'Update-MT7629-to-support-PHYLINK-API'
  4e3eff5beafa net: ethernet: mediatek: Fix MT7629 missing GMII mode support
  cab209e571a9 tcp: fix a possible lockdep splat in tcp_done()
  8d045995ed5b Merge branch 'mpls-push-pop-fix'
  b790b5549bdf net: dsa: sja1105: Use the correct style for SPDX License Identifier
  39f13ea2f61b net: avoid potential infinite loop in tc_ctl_action()
  fa4e0f8855fc net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions
  28aa7c86c2b4 sched: etf: Fix ordering of packets with same txtime
  dedc5a08da07 net: avoid errors when trying to pop MLPS header on non-MPLS packets
  63dfb7938b13 sctp: change sctp_prot .no_autobind with true
  a03681dd5d1b net: cavium: Use the correct style for SPDX License Identifier
  61c1d33daf7b net: i82596: fix dma_alloc_attr for sni_82596
  b31141d390f1 net: dsa: microchip: Use the correct style for SPDX License Identifier
  539825a53604 davinci_cpdma: make cpdma_chan_split_pool static
  ddc790e92b3a net: ethernet: broadcom: have drivers select DIMLIB as needed
  bad28d889cae net: stmmac: make tc_flow_parsers static
  f913eac8e555 net: Update address for vrf and l3mdev in MAINTAINERS
  92696286f3bb net: bcmgenet: Set phydev->dev_flags only for internal PHYs
  efb86fede98c net: bcmgenet: Fix RGMII_MODE_EN value for GENET v1/2/3
  77b6d09f4ae6 net: usb: sr9800: fix uninitialized local variable
  b0818f80c8c1 blackhole_netdev: fix syzkaller reported issue
  bd74708cd979 Revert "blackhole_netdev: fix syzkaller reported issue"

similar bugs (2):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	INFO: task hung in rtnetlink_rcv_msg (2)				1	6d07h	6d07h	0/1	upstream: reported on 2021/07/23 04:37
linux-4.19	INFO: task hung in rtnetlink_rcv_msg				11	258d	580d	0/1	auto-closed as invalid on 2021/03/12 19:03

Sample crash report:

INFO: task syz-executor725:8005 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D27984  8005   7591 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac037 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8008 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D27552  8008   7590 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03d R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8009 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28008  8009   7595 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03d R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8010 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28000  8010   7596 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03e R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor725:8011 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6+ #75
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor725 D28008  8011   7594 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3587
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 <7a> fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd ff 11 7a fd
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac03b R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
3 locks held by kworker/1:1/22:
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000009b0b09b4 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2144
 #1: 00000000e8391065 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2148
 #2: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
1 lock held by khungtaskd/1040:
 #0: 00000000083344d4 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4389
1 lock held by rsyslogd/7472:
 #0: 000000007562dcc1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:795
2 locks held by getty/7562:
 #0: 000000000837ceb2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000d91e6e17 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7563:
 #0: 00000000243db696 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000000002034d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7564:
 #0: 00000000a59e483b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000004032d53a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7565:
 #0: 0000000025343c97 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000727bf19a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7566:
 #0: 000000003dac20af (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000fef38c44 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7567:
 #0: 00000000da1bfc9c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000f82cf636 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
2 locks held by getty/7568:
 #0: 00000000a5d9fcdf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000005ae165cb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154
1 lock held by syz-executor725/8002:
1 lock held by syz-executor725/8005:
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8008:
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8009:
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8010:
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127
1 lock held by syz-executor725/8011:
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000da1e0257 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:5127

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc6+ #75
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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 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+0x9df/0xee0 kernel/hung_task.c:287
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.415 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 8002 Comm: syz-executor725 Not tainted 5.0.0-rc6+ #75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unwind_next_frame.part.0+0x1a8/0x9a0 arch/x86/kernel/unwind_frame.c:329
Code: 8b 6d 20 4c 89 ee 48 89 df 4c 89 95 60 ff ff ff 4c 89 9d 68 ff ff ff 4c 89 8d 70 ff ff ff e8 6f f7 ff ff 4c 8b 8d 70 ff ff ff <41> 89 c0 4c 8b 9d 68 ff ff ff b8 01 00 00 00 45 84 c0 4c 8b 95 60
RSP: 0018:ffff888096136e28 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff888096136f00 RCX: 1ffff11012c26de8
RDX: dffffc0000000000 RSI: 1ffff11012c26d00 RDI: ffff888096136f48
RBP: ffff888096136ed8 R08: 0000000000000001 R09: ffff888096136f50
R10: ffff888096136f28 R11: ffff888096136f38 R12: 1ffff11012c26dca
R13: ffff888096137b70 R14: ffff888096137b40 R15: ffff888096137f58
FS:  00000000024b2880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 000000009810b000 CR4: 00000000001406e0
Call Trace:
 unwind_next_frame+0x3b/0x50 arch/x86/kernel/unwind_frame.c:287
 __save_stack_trace+0x7a/0xf0 arch/x86/kernel/stacktrace.c:44
 save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
 __do_kmalloc_node mm/slab.c:3673 [inline]
 __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3687
 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:140
 pskb_expand_head+0x14e/0xdd0 net/core/skbuff.c:1465
 netlink_trim+0x215/0x270 net/netlink/af_netlink.c:1292
 netlink_unicast+0xbf/0x720 net/netlink/af_netlink.c:1326
 rtnetlink_send+0xf0/0x110 net/core/rtnetlink.c:721
 tcf_add_notify net/sched/act_api.c:1325 [inline]
 tcf_action_add+0x243/0x370 net/sched/act_api.c:1344
 tc_ctl_action+0x3b6/0x4bd net/sched/act_api.c:1392
 rtnetlink_rcv_msg+0x465/0xb00 net/core/rtnetlink.c:5130
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5148
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x806/0x930 net/socket.c:2114
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2152
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg net/socket.c:2159 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4459f9
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdc979ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004459f9
RDX: 00000000000000c4 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000000ac031 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000200015a6 R11: 0000000000000246 R12: 0000000000406890
R13: 0000000000406920 R14: 0000000000000000 R15: 0000000000000000

Crashes (98):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci-upstream-kasan-gce-root	2019/02/17 08:10	upstream	64c0133eb88a	f42dee6d	.config	log	report	syz	C
ci-upstream-kasan-gce-smack-root	2019/02/17 07:52	upstream	64c0133eb88a	f42dee6d	.config	log	report	syz	C
ci-upstream-net-this-kasan-gce	2019/02/16 09:43	net	24f0a48743a2	f42dee6d	.config	log	report	syz	C
ci-upstream-net-kasan-gce	2020/10/06 07:58	net-next	c2568c8c9e63	1880b4a9	.config	log	report	syz	C
ci-upstream-net-kasan-gce	2019/02/16 15:27	net-next	bb015f2216fe	f42dee6d	.config	log	report	syz	C
ci-upstream-linux-next-kasan-gce-root	2021/01/06 23:52	linux-next	7e4525a4232f	c104d4a3	.config	log	report	syz	C
ci-upstream-linux-next-kasan-gce-root	2019/02/16 09:44	linux-next	7a92eb7cc1dc	f42dee6d	.config	log	report	syz	C
ci-upstream-kasan-gce-root	2021/07/19 02:03	upstream	1d67c8d993ba	f115ae98	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-kasan-gce-root	2021/04/23 16:47	upstream	18a3c5f7abfd	17f0b706	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-kasan-gce-smack-root	2021/02/12 14:52	upstream	dcc0b49040c7	a5f86b15	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-kasan-gce-root	2021/01/31 00:00	upstream	8c947645151c	fc9fd31e	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-kasan-gce	2021/01/26 07:28	upstream	f8ad8187c3b5	52e37319	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/07/18 01:08	net	5b69874f74cc	f115ae98	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-bpf-kasan-gce	2021/06/28 22:55	bpf	d6765985a42a	9d2ab5df	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/04/13 14:08	net	ccb39c628558	bfeda1b1	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/02/12 10:34	net	308daa19e2d0	a5f86b15	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/02/09 23:27	net	6bbc088d6ebf	2bd9619f	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/02/09 08:44	net	af8085f3a471	2bd9619f	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/02/08 00:03	net	225353c070fd	2ce644fc	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/02/07 14:26	net	225353c070fd	2ce644fc	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-this-kasan-gce	2021/01/29 07:29	net	909b447dcc45	7df34f59	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-kasan-gce	2021/07/06 09:07	net-next	5e437416ff66	6c4484eb	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-kasan-gce	2021/06/13 20:49	net-next	ffbbc5e5c717	1ba81399	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-net-kasan-gce	2021/04/14 18:02	net-next	5871d0c6b8ea	3134b37f	.config	log	report			info	INFO: task hung in rtnetlink_rcv_msg
ci-upstream-kasan-gce	2021/01/07 16:12	upstream	71c061d24438	c104d4a3	.config	log	report			info
ci-upstream-kasan-gce	2020/12/27 11:34	upstream	f838f8d2b694	821e0b09	.config	log	report			info
ci-upstream-kasan-gce	2020/11/27 23:21	upstream	99c710c46dfc	486f93ef	.config	log	report			info
ci-upstream-kasan-gce-smack-root	2020/11/19 07:48	upstream	c2e7554e1b85	0767f13f	.config	log	report			info
ci-upstream-kasan-gce-selinux-root	2020/10/07 20:47	upstream	c85fb28b6f99	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce-root	2020/10/07 12:47	upstream	c85fb28b6f99	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce-selinux-root	2020/10/07 05:14	upstream	c85fb28b6f99	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce-root	2020/10/07 01:14	upstream	c85fb28b6f99	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce	2020/10/06 10:12	upstream	7575fdda569b	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce-root	2020/10/06 01:37	upstream	7575fdda569b	1880b4a9	.config	log	report			info
ci-upstream-kasan-gce	2020/10/01 12:13	upstream	60e720931556	a9767fb2	.config	log	report			info
ci-qemu-upstream	2019/11/30 13:21	upstream	81b6b96475ac	3a75be00	.config	log	report
ci-upstream-kasan-gce-386	2020/10/06 21:43	upstream	7575fdda569b	1880b4a9	.config	log	report			info
ci-upstream-net-this-kasan-gce	2021/01/01 21:12	net	4bfc4714849d	79264ae3	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/12/17 22:38	net	3ae32c07815a	04201c06	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/15 23:33	net	2ecbc1f68448	6e262c73	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/05 18:20	net	4296adc3e32f	1880b4a9	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/03 11:59	net	ab0faf5f04e8	2653fa43	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/03 09:12	net	ab0faf5f04e8	2653fa43	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/02 23:00	net	ef9da46ddef0	4969d6ca	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/02 20:21	net	ef9da46ddef0	4969d6ca	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/02 18:23	net	ef9da46ddef0	4969d6ca	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/02 17:23	net	ef9da46ddef0	4969d6ca	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/02 01:23	net	bb13a800620c	9602ddf4	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/01 16:48	net	a59cf619787e	a9767fb2	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/01 08:29	net	a59cf619787e	a9767fb2	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/10/01 02:13	net	2b3e981a94d8	8516f6d3	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/30 15:33	net	2b3e981a94d8	8516f6d3	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/30 10:44	net	c92a79829c7c	5abc3f1a	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/30 10:42	net	c92a79829c7c	5abc3f1a	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/29 18:27	net	1aad8049909a	1b88c6d5	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/29 15:50	net	1aad8049909a	1b88c6d5	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/29 15:10	net	1aad8049909a	1b88c6d5	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/29 08:33	net	1aad8049909a	1b88c6d5	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/28 12:13	net	709a16be0593	6bfdbe89	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/28 03:54	net	307eea32b202	5dd8aee8	.config	log	report			info
ci-upstream-net-this-kasan-gce	2020/09/27 03:39	net	059432495e20	2d5ea0cb	.config	log	report			info
ci-upstream-net-kasan-gce	2020/12/30 17:05	net-next	3db1a3fa9880	ecb8c012	.config	log	report			info
ci-upstream-net-kasan-gce	2020/10/16 04:02	net-next	346e320cb210	6e262c73	.config	log	report			info
ci-upstream-net-kasan-gce	2020/10/09 07:23	net-next	9d49aea13f1e	92390980	.config	log	report			info