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INFO: task hung in lock_sock_nested (2)

Status: auto-closed as invalid on 2020/11/24 03:07
Reported-by: syzbot+db451aa5984dd5e2d283@syzkaller.appspotmail.com
First crash: 1578d, last: 1578d
▶ ▼ Similar bugs (15)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lock_sock_nested (2) net C done 418 1721d 1734d 15/28 fixed on 2020/04/15 17:19
upstream INFO: task hung in lock_sock_nested net C 2593 1738d 2538d 0/28 closed as dup on 2017/12/23 20:15
android-44 INFO: task hung in lock_sock_nested (2) 4 1820d 1916d 0/2 auto-closed as invalid on 2020/03/27 01:37
linux-4.19 INFO: task hung in lock_sock_nested (3) 6 667d 881d 0/1 upstream: reported on 2022/06/23 22:52
upstream INFO: task hung in lock_sock_nested (3) net C done 5 1509d 1511d 15/28 fixed on 2020/11/16 12:12
android-49 INFO: task hung in lock_sock_nested (2) 2 1899d 2018d 0/3 auto-closed as invalid on 2020/01/08 15:18
linux-4.14 INFO: task hung in lock_sock_nested 1 1841d 1841d 0/1 auto-closed as invalid on 2020/03/06 15:38
android-44 INFO: task hung in lock_sock_nested C 82 2458d 2460d 0/2 closed as invalid on 2019/03/08 00:11
upstream INFO: task can't die in __lock_sock bluetooth C done error 1067 380d 1194d 0/28 auto-obsoleted due to no activity on 2024/01/16 13:36
upstream INFO: task hung in lock_sock_nested (4) mptcp C done 6 1404d 1450d 19/28 fixed on 2021/03/10 01:48
android-49 INFO: task hung in lock_sock_nested C 101 2098d 2460d 0/3 closed as invalid on 2019/03/08 00:11
android-414 INFO: task hung in lock_sock_nested 65 1864d 2049d 0/1 auto-closed as invalid on 2020/02/12 04:11
linux-4.19 INFO: task hung in lock_sock_nested (2) 1 1078d 1078d 0/1 auto-closed as invalid on 2022/04/08 17:15
linux-5.15 INFO: task hung in lock_sock_nested 1 100d 100d 0/3 auto-obsoleted due to no activity on 2024/11/21 04:55
linux-4.19 INFO: task hung in lock_sock_nested 1 1657d 1657d 0/1 auto-closed as invalid on 2020/09/05 19:53

Sample crash report:
 __do_page_fault+0x578/0xb50 arch/x86/mm/fault.c:1442
 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123
RIP: 17cee60:0x1d1bb8626e1
RSP: 4211af:000000c000009960 EFLAGS: 00000003
INFO: task syz-executor.3:7838 blocked for more than 140 seconds.
      Not tainted 4.14.189-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D26544  7838   6367 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 __lock_sock+0x118/0x1f0 net/core/sock.c:2245
 lock_sock_nested+0xe1/0x100 net/core/sock.c:2769
 lock_sock include/net/sock.h:1467 [inline]
 sctp_wait_for_connect+0x27a/0x430 net/sctp/socket.c:8017
Mem-Info:
active_anon:332075 inactive_anon:8792 isolated_anon:0
 active_file:49 inactive_file:751 isolated_file:0
 unevictable:0 dirty:0 writeback:0 unstable:0
 slab_reclaimable:15740 slab_unreclaimable:1115504
 mapped:43550 shmem:12686 pagetables:19051 bounce:0
 free:24957 free_pcp:29 free_cma:0
 __sctp_connect+0x9c0/0xbe0 net/sctp/socket.c:1265
Node 0 active_anon:1303724kB inactive_anon:29740kB active_file:176kB inactive_file:3064kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:174204kB dirty:0kB writeback:0kB shmem:39080kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 1099776kB writeback_tmp:0kB unstable:0kB all_unreclaimable? yes
 sctp_connect net/sctp/socket.c:4196 [inline]
 sctp_inet_connect+0x127/0x190 net/sctp/socket.c:4211
Node 1 active_anon:24576kB inactive_anon:5428kB active_file:0kB inactive_file:8kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:0kB writeback:0kB shmem:11664kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no
 SYSC_connect net/socket.c:1655 [inline]
 SyS_connect+0x1f4/0x240 net/socket.c:1636
Node 0 DMA free:10432kB min:220kB low:272kB high:324kB active_anon:4212kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15992kB managed:15908kB mlocked:0kB kernel_stack:0kB pagetables:96kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45c369
RSP: 002b:00007fc817ec8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000000022c0 RCX: 000000000045c369
lowmem_reserve[]: 0 2557 2557 2557 2557
RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
Node 0 
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
DMA32 free:36008kB min:36272kB low:45340kB high:54408kB active_anon:1299512kB inactive_anon:29740kB active_file:176kB inactive_file:2936kB unevictable:0kB writepending:0kB present:3129332kB managed:2621252kB mlocked:0kB kernel_stack:29728kB pagetables:61992kB bounce:0kB free_pcp:112kB local_pcp:112kB free_cma:0kB
R13: 00007fff461d0e3f R14: 00007fc817ec99c0 R15: 000000000078bf0c

Showing all locks held in the system:
lowmem_reserve[]: 0 0 0 0 0
Node 0 Normal free:0kB min:4kB low:4kB high:4kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:786432kB managed:340kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
lowmem_reserve[]: 0 0 0 0 0
Node 1 Normal free:53544kB min:53612kB low:67012kB high:80412kB active_anon:24576kB inactive_anon:5428kB active_file:32kB inactive_file:0kB unevictable:0kB writepending:0kB present:3932160kB managed:3870192kB mlocked:0kB kernel_stack:9664kB pagetables:14116kB bounce:0kB free_pcp:120kB local_pcp:120kB free_cma:0kB
lowmem_reserve[]: 0 0 0 0 0
Node 0 DMA: 8*4kB (UM) 6*8kB (UM) 5*16kB (UM) 1*32kB (M) 2*64kB (M) 3*128kB (UM) 0*256kB 3*512kB (UM) 2*1024kB (UM) 1*2048kB (U) 1*4096kB (E) = 10432kB
1 lock held by khungtaskd/1061:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff81477894>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by agetty/6049:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff8343c652>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff834319a3>] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156
2 locks held by syz-executor.3/7849:
 #0:  (sk_lock-AF_INET6){+.+.}, at: [<ffffffff85e2d171>] lock_sock include/net/sock.h:1467 [inline]
 #0:  (sk_lock-AF_INET6){+.+.}, at: [<ffffffff85e2d171>] sctp_sendmsg+0x6f1/0x2cd0 net/sctp/socket.c:1759
 #1:  (pcpu_drain_mutex){+.+.}, at: [<ffffffff8170ec5a>] drain_all_pages+0x4a/0x570 mm/page_alloc.c:2494

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

Node 0 DMA32: 4279*4kB (UME) 1394*8kB (UME) 373*16kB (UME) 50*32kB (UM) 2*64kB (U) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 35964kB
Node 0 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 0kB
Node 1 Normal: 1367*4kB (ME) 793*8kB (UME) 419*16kB (UME) 263*32kB (ME) 145*64kB (ME) 82*128kB (UME) 15*256kB (UM) 6*512kB (ME) 0*1024kB 0*2048kB 0*4096kB = 53620kB
Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
NMI backtrace for cpu 0
CPU: 0 PID: 1061 Comm: khungtaskd Not tainted 4.14.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x17f 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
Node 1 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
 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: 6006 Comm: in:imklog Not tainted 4.14.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880a4bfc4c0 task.stack: ffff8880856d8000
RIP: 0010:mark_lock+0x2c/0x1050 kernel/locking/lockdep.c:3162
RSP: 0000:ffff8880856def88 EFLAGS: 00000806
RAX: dffffc0000000000 RBX: 0000000000000002 RCX: 0000000000000008
RDX: 1ffff1101497f9b7 RSI: ffff8880a4bfcd98 RDI: ffff8880a4bfc4c0
RBP: ffff8880a4bfcdba R08: 0000000000000001 R09: 00000000000c022c
R10: ffff8880a4bfcd98 R11: ffff8880a4bfc4c0 R12: 0000000000000001
R13: ffff8880a4bfc4c0 R14: ffff8880a4bfcdb8 R15: 0000000000000008
FS:  00007f6f10e9e700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f8bd75650 CR3: 000000008ca9d000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __lock_acquire+0x5fc/0x3f20 kernel/locking/lockdep.c:3452
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x8c/0xc0 kernel/locking/spinlock.c:160
 __remove_mapping+0x9f/0x760 mm/vmscan.c:689
 shrink_page_list+0x1c91/0x2c10 mm/vmscan.c:1320
 shrink_inactive_list+0x31e/0xe90 mm/vmscan.c:1825
 shrink_list mm/vmscan.c:2177 [inline]
 shrink_node_memcg+0x7a8/0x1190 mm/vmscan.c:2445
 shrink_node.isra.0+0x2c6/0xb30 mm/vmscan.c:2637
 shrink_zones mm/vmscan.c:2819 [inline]
 do_try_to_free_pages+0x34b/0xde0 mm/vmscan.c:2877
 try_to_free_pages+0x203/0x6e0 mm/vmscan.c:3083
 __perform_reclaim mm/page_alloc.c:3582 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:3603 [inline]
 __alloc_pages_slowpath mm/page_alloc.c:3990 [inline]
 __alloc_pages_nodemask+0xc84/0x2720 mm/page_alloc.c:4199
 alloc_pages_current+0x155/0x260 mm/mempolicy.c:2113
 alloc_pages include/linux/gfp.h:520 [inline]
 __page_cache_alloc mm/filemap.c:871 [inline]
 page_cache_read mm/filemap.c:2296 [inline]
 filemap_fault+0xe12/0x18d0 mm/filemap.c:2480
 ext4_filemap_fault+0x84/0xb0 fs/ext4/inode.c:6233
 __do_fault+0xfa/0x380 mm/memory.c:3223
 do_read_fault mm/memory.c:3633 [inline]
 do_fault mm/memory.c:3759 [inline]
 handle_pte_fault mm/memory.c:3989 [inline]
 __handle_mm_fault+0x2497/0x4620 mm/memory.c:4113
 handle_mm_fault+0x306/0x7a0 mm/memory.c:4150
 __do_page_fault+0x578/0xb50 arch/x86/mm/fault.c:1442
 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123
RIP: 10e7d0b0:0x1f9f
RSP: 12670fe6:00007f6f10e7d0a0 EFLAGS: 7f6f10e7d1d8
Code: b8 00 00 00 00 00 fc ff df 41 57 89 d1 41 89 d7 41 56 4c 8d 76 20 4c 89 f2 41 55 49 89 fd 41 54 48 c1 ea 03 41 bc 01 00 00 00 55 <41> d3 e4 48 89 f5 53 48 83 ec 18 0f b6 04 02 84 c0 74 08 3c 01

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/07/27 03:06 linux-4.14.y 69b94dd6dcd1 51265195 .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.