BUG: soft lockup in sys_mbind

Status: upstream: reported syz repro on 2021/05/05 05:15
Reported-by: syzbot+a1361300da931b3e3373@syzkaller.appspotmail.com
First crash: 1928d, last: 1928d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mbind mm kasan 1 2 187d 242d 0/29 auto-obsoleted due to no activity on 2026/05/09 19:34
upstream INFO: rcu detected stall in sys_mbind (5) bpf 1 1 524d 524d 0/29 auto-obsoleted due to no activity on 2025/06/07 08:47
upstream INFO: rcu detected stall in sys_mbind (4) mm 1 1 721d 721d 0/29 auto-obsoleted due to no activity on 2024/11/22 04:15
upstream INFO: rcu detected stall in sys_mbind (3) cgroups mm 1 1 793d 793d 0/29 auto-obsoleted due to no activity on 2024/08/12 04:57

Sample crash report:
Bluetooth: hci5: command 0x0406 tx timeout
Bluetooth: hci4: command 0x0406 tx timeout
Bluetooth: hci1: command 0x0406 tx timeout
Bluetooth: hci3: command 0x0406 tx timeout
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz-executor.2:14798]
Modules linked in:
irq event stamp: 2572052
hardirqs last  enabled at (2572051): [<ffffffff81003ce4>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (2572052): [<ffffffff81003d00>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (112472): [<ffffffff88400678>] __do_softirq+0x678/0x980 kernel/softirq.c:318
softirqs last disabled at (65753): [<ffffffff813926d5>] invoke_softirq kernel/softirq.c:372 [inline]
softirqs last disabled at (65753): [<ffffffff813926d5>] irq_exit+0x215/0x260 kernel/softirq.c:412
CPU: 0 PID: 14798 Comm: syz-executor.2 Not tainted 4.19.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rep_nop arch/x86/include/asm/processor.h:656 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:661 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:438 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3a4/0xae0 kernel/locking/qspinlock.c:474
Code: 48 89 eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c <f3> 90 41 83 ec 01 0f 84 38 04 00 00 41 0f b6 45 00 38 d8 7f 08 84
RSP: 0018:ffff8880b4037940 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff1404194
RDX: 0000000000000001 RSI: ffffffff81678725 RDI: 0000000000000282
RBP: ffffffff8a020ca0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000004d7d
R13: fffffbfff1404194 R14: 0000000000000001 R15: ffff8880ba02bd80
FS:  00007fe8495c8700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f53f9764718 CR3: 00000000b4726000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:53 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
 do_raw_spin_lock+0x189/0x220 kernel/locking/spinlock_debug.c:113
 spin_lock include/linux/spinlock.h:329 [inline]
 isolate_huge_page+0x75/0x430 mm/hugetlb.c:4987
 queue_pages_hugetlb+0x38b/0x610 mm/mempolicy.c:575
 walk_hugetlb_range+0x1dc/0x3c0 mm/pagewalk.c:193
 __walk_page_range mm/pagewalk.c:252 [inline]
 __walk_page_range mm/pagewalk.c:244 [inline]
 walk_page_range+0x382/0x490 mm/pagewalk.c:335
 queue_pages_range+0x107/0x150 mm/mempolicy.c:692
 do_mbind+0x2c2/0xd60 mm/mempolicy.c:1274
 kernel_mbind mm/mempolicy.c:1409 [inline]
 __do_sys_mbind mm/mempolicy.c:1416 [inline]
 __se_sys_mbind mm/mempolicy.c:1412 [inline]
 __x64_sys_mbind+0x235/0x290 mm/mempolicy.c:1412
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe8495c8188 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000020196000
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffd641c31af R14: 00007fe8495c8300 R15: 0000000000022000
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 14791 Comm: syz-executor.5 Not tainted 4.19.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:preempt_count_sub+0x63/0x150 kernel/sched/core.c:3274
Code: 75 18 65 8b 05 2e 75 c0 7e 25 ff ff ff 7f 39 c3 7f 1a 81 fb fe 00 00 00 76 6a 65 8b 05 16 75 c0 7e f7 db 65 01 1d 0d 75 c0 7e <5b> c3 e8 c6 a1 31 02 85 c0 74 f5 48 c7 c0 c0 d6 36 8d 48 ba 00 00
RSP: 0018:ffff8880ba1072d0 EFLAGS: 00000213
RAX: 0000000000000303 RBX: 00000000ffffffff RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffff8880ba107270 RDI: 0000000000000001
RBP: ffff8880ba107f30 R08: 0000000000000001 R09: 0000000000000001
R10: ffff8880ba10746f R11: 0000000000074071 R12: ffff8880ba100000
R13: ffff8880ba107445 R14: ffff8880ba107410 R15: ffffffff8b93e482
FS:  00007feb617a6700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200001c0 CR3: 00000000a638a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 unwind_next_frame+0xeee/0x1400 arch/x86/kernel/unwind_orc.c:579
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3397 [inline]
 __do_kmalloc mm/slab.c:3725 [inline]
 __kmalloc+0x144/0x3c0 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 neigh_alloc net/core/neighbour.c:326 [inline]
 __neigh_create+0x218/0x1c40 net/core/neighbour.c:501
 ip6_finish_output2+0x8cc/0x2290 net/ipv6/ip6_output.c:117
 ip6_finish_output+0x795/0xe50 net/ipv6/ip6_output.c:192
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209
 dst_output include/net/dst.h:455 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ndisc_send_skb+0xa24/0x1720 net/ipv6/ndisc.c:491
 ndisc_send_rs+0x131/0x690 net/ipv6/ndisc.c:685
 addrconf_rs_timer+0x384/0x6a0 net/ipv6/addrconf.c:3835
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1696 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709
 __do_softirq+0x265/0x980 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:535 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184
Code: 48 c7 c0 48 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d dc 88 d9 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 9b 43 e8 f8 eb c0 0f 0b 0f 0b 48 c7 c7 48
RSP: 0018:ffff8880818479b8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e3049 RBX: 0000000000000282 RCX: 1ffff110128bcd22
RDX: dffffc0000000000 RSI: ffff8880945e68f0 RDI: 0000000000000282
RBP: ffffffff8d3fadc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000200
R13: ffff88807e600000 R14: 0000000000000004 R15: dffffc0000000000
 __debug_check_no_obj_freed lib/debugobjects.c:798 [inline]
 debug_check_no_obj_freed+0x201/0x490 lib/debugobjects.c:817
 free_pages_prepare mm/page_alloc.c:1056 [inline]
 __free_pages_ok+0x22d/0xd30 mm/page_alloc.c:1279
 update_and_free_page+0x839/0xb70 mm/hugetlb.c:1195
 free_huge_page+0xa5b/0xd20 mm/hugetlb.c:1304
 __put_page+0xe2/0x3a0 mm/swap.c:112
 put_page include/linux/mm.h:963 [inline]
 putback_active_hugepage+0x624/0x7c0 mm/hugetlb.c:5007
 unmap_and_move_huge_page mm/migrate.c:1355 [inline]
 migrate_pages+0x1a07/0x2fe0 mm/migrate.c:1415
 do_mbind+0xaaf/0xd60 mm/mempolicy.c:1289
 kernel_mbind mm/mempolicy.c:1409 [inline]
 __do_sys_mbind mm/mempolicy.c:1416 [inline]
 __se_sys_mbind mm/mempolicy.c:1412 [inline]
 __x64_sys_mbind+0x235/0x290 mm/mempolicy.c:1412
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feb617a6188 EFLAGS: 00000246 ORIG_RAX: 00000000000000ed
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000020196000
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff1e6cf18f R14: 00007feb617a6300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/05 05:14 linux-4.19.y 97a8651cadce 06c27ff5 .config console log report syz ci2-linux-4-19 BUG: soft lockup in sys_mbind
* Struck through repros no longer work on HEAD.