INFO: task hung in raw_close (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: dffb5c6ff09c Linux 4.14.280
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10d49e6ef00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9bde605ce69ece2e
dashboard link: https://syzkaller.appspot.com/bug?extid=4622c92314002f1e9dd3
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4622c9...@syzkaller.appspotmail.com

Bluetooth: hci5 command 0x0406 tx timeout
Bluetooth: hci1 command 0x0406 tx timeout
Bluetooth: hci3 command 0x0406 tx timeout
Bluetooth: hci4 command 0x0406 tx timeout
Bluetooth: hci0 command 0x0406 tx timeout
INFO: task syz-executor.4:9764 blocked for more than 140 seconds.
Not tainted 4.14.280-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4 D25056 9764 7977 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2811 [inline]
__schedule+0x88b/0x1de0 kernel/sched/core.c:3387
schedule+0x8d/0x1b0 kernel/sched/core.c:3431
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489
__mutex_lock_common kernel/locking/mutex.c:833 [inline]
__mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
raw_close+0xe/0x30 net/ipv4/raw.c:701
inet_release+0xdf/0x1b0 net/ipv4/af_inet.c:425
__sock_release+0xcd/0x2b0 net/socket.c:602
sock_close+0x15/0x20 net/socket.c:1139
__fput+0x25f/0x7a0 fs/file_table.c:210
task_work_run+0x11f/0x190 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:191 [inline]
exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f8223ce0d2b
RSP: 002b:00007ffd271a53f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007f8223ce0d2b
RDX: 0000000000000000 RSI: 0000001b2e02773c RDI: 0000000000000006
RBP: 00007f8223e42960 R08: 0000000000000000 R09: 0000000052e89d15
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000001dfcd
R13: 00007ffd271a54f0 R14: 00007ffd271a5510 R15: 0000000000000032

Showing all locks held in the system:
3 locks held by kworker/1:1/23:
#0: ("%s"("ipv6_addrconf")){+.+.}, at: [<ffffffff81364f80>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088
#1: ((addr_chk_work).work){+.+.}, at: [<ffffffff81364fb6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
#2: (rtnl_mutex){+.+.}, at: [<ffffffff8637114a>] addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4420
1 lock held by khungtaskd/1532:
#0: (tasklist_lock){.+.+}, at: [<ffffffff87026b2c>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by syz-executor.1/9719:
#0: (rtnl_mutex){+.+.}, at: [<ffffffff85c556ce>] netdev_run_todo+0x20e/0xad0 net/core/dev.c:7934
1 lock held by syz-executor.0/9721:
#0: (rtnl_mutex){+.+.}, at: [<ffffffff85c556ce>] netdev_run_todo+0x20e/0xad0 net/core/dev.c:7934
1 lock held by syz-executor.5/9732:
#0: (rtnl_mutex){+.+.}, at: [<ffffffff83d55e14>] tun_detach drivers/net/tun.c:593 [inline]
#0: (rtnl_mutex){+.+.}, at: [<ffffffff83d55e14>] tun_chr_close+0x34/0x60 drivers/net/tun.c:2732
2 locks held by syz-executor.2/9762:
#0: (rtnl_mutex){+.+.}, at: [<ffffffff83f9df6b>] ppp_release+0xdb/0x1a0 drivers/net/ppp/ppp_generic.c:408
#1: (uevent_sock_mutex){+.+.}, at: [<ffffffff86fe7035>] kobject_uevent_env+0x755/0xf30 lib/kobject_uevent.c:460
2 locks held by syz-executor.4/9764:
#0: (&sb->s_type->i_mutex_key#13){+.+.}, at: [<ffffffff85bca2c6>] inode_lock include/linux/fs.h:719 [inline]
#0: (&sb->s_type->i_mutex_key#13){+.+.}, at: [<ffffffff85bca2c6>] __sock_release+0x86/0x2b0 net/socket.c:601
#1: (rtnl_mutex){+.+.}, at: [<ffffffff86197c6e>] raw_close+0xe/0x30 net/ipv4/raw.c:701

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

NMI backtrace for cpu 0
CPU: 0 PID: 1532 Comm: khungtaskd Not tainted 4.14.280-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
watchdog+0x5b9/0xb40 kernel/hung_task.c:274
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.14.280-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880b54b4480 task.stack: ffff8880b54b8000
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:774 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:796 [inline]
RIP: 0010:lock_is_held_type+0x82/0x210 kernel/locking/lockdep.c:4032
RSP: 0018:ffff8880b54bf4d0 EFLAGS: 00000282
RAX: 0000000000000282 RBX: ffff8880b54b4480 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 00000000ffffffff RDI: ffff8880b54b4d04
RBP: ffffffff89ce7de0 R08: 0000000000000000 R09: 0000000000022012
R10: ffff8880b54b4d58 R11: ffff8880b54b4480 R12: ffff8880a4918020
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880aace4b60
FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4b95de2150 CR3: 00000000a160e000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_is_held include/linux/lockdep.h:437 [inline]
lockdep_rtnl_is_held+0x16/0x20 net/core/rtnetlink.c:125
fib_table_lookup+0x2a2/0x1680 net/ipv4/fib_trie.c:1358
fib_lookup include/net/ip_fib.h:326 [inline]
__fib_validate_source net/ipv4/fib_frontend.c:344 [inline]
fib_validate_source+0x678/0x17d0 net/ipv4/fib_frontend.c:413
ip_route_input_slow+0x228e/0x2de0 net/ipv4/route.c:2037
ip_route_input_rcu net/ipv4/route.c:2214 [inline]
ip_route_input_noref+0xec/0x200 net/ipv4/route.c:2159
ip_rcv_finish+0x2ea/0x19f0 net/ipv4/ip_input.c:347
NF_HOOK include/linux/netfilter.h:250 [inline]
ip_rcv+0x8a7/0xf10 net/ipv4/ip_input.c:493
__netif_receive_skb_core+0x15ee/0x2a30 net/core/dev.c:4474
__netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
napi_skb_finish net/core/dev.c:4947 [inline]
napi_gro_receive+0x2e2/0x400 net/core/dev.c:4978
gro_cell_poll+0x119/0x1d0 net/core/gro_cells.c:60
napi_poll net/core/dev.c:5604 [inline]
net_rx_action+0x466/0xfd0 net/core/dev.c:5670
__do_softirq+0x24d/0x9ff kernel/softirq.c:288
run_ksoftirqd+0x50/0x1a0 kernel/softirq.c:670
smpboot_thread_fn+0x5c1/0x920 kernel/smpboot.c:164
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 98 f0 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 6a 01 00 00 48 83 3d c6 5f af 07 00 0f 84 1d 01 00 00 9c 58 <0f> 1f 44 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c3 48 c7 c0
----------------
Code disassembly (best guess), 3 bytes skipped:
0: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
7: fc ff df
a: 48 c1 e8 03 shr $0x3,%rax
e: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1)
12: 0f 85 6a 01 00 00 jne 0x182
18: 48 83 3d c6 5f af 07 cmpq $0x0,0x7af5fc6(%rip) # 0x7af5fe6
1f: 00
20: 0f 84 1d 01 00 00 je 0x143
26: 9c pushfq
27: 58 pop %rax
* 28: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) <-- trapping instruction
2d: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
34: fc ff df
37: 48 89 c3 mov %rax,%rbx
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: c0 .byte 0xc0


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.