syzbot


BUG: soft lockup in sys_unshare

Status: premoderation: reported on 2024/05/05 08:22
Reported-by: syzbot+2fcd0850a9bdb2fda156@syzkaller.appspotmail.com
First crash: 45d, last: 45d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_unshare (5) net 1 887d 887d 0/27 closed as invalid on 2022/02/08 10:10
upstream INFO: rcu detected stall in sys_unshare (3) net 1 1110d 1110d 0/27 auto-closed as invalid on 2021/09/03 04:28
linux-5.15 INFO: rcu detected stall in sys_unshare origin:upstream C 2 27d 30d 0/3 upstream: reported C repro on 2024/05/20 16:51
upstream INFO: rcu detected stall in sys_unshare (6) kernfs 1 856d 856d 0/27 auto-closed as invalid on 2022/05/15 15:21
upstream INFO: rcu detected stall in sys_unshare (9) bpf C inconclusive 5 2d11h 221d 0/27 upstream: reported C repro on 2023/11/11 00:17
upstream INFO: rcu detected stall in sys_unshare (4) kernel 1 1019d 1019d 0/27 auto-closed as invalid on 2021/12/03 09:38
upstream INFO: rcu detected stall in sys_unshare (7) bpf net 12 472d 603d 0/27 auto-obsoleted due to no activity on 2023/06/03 15:22
linux-6.1 INFO: rcu detected stall in sys_unshare origin:upstream C 1 27d 198d 0/3 upstream: reported C repro on 2023/12/04 08:29

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz-executor.4:21884]
Modules linked in:
CPU: 0 PID: 21884 Comm: syz-executor.4 Not tainted 5.15.149-syzkaller-00490-g5d96939590c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc900013b7480 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 1ffff92000276e94 RCX: ffffffff8154fa7f
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff8881284e42a8
RBP: ffffc900013b7530 R08: dffffc0000000000 R09: ffffed102509c856
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881284e42a8 R14: 0000000000000003 R15: 1ffff92000276e98
FS:  00007f7a7612f6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffc213405c CR3: 0000000116164000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x6bc/0xc40 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x248
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 sk_psock_free_link include/linux/skmsg.h:420 [inline]
 sock_map_del_link net/core/sock_map.c:160 [inline]
 sock_map_unref+0x352/0x4d0 net/core/sock_map.c:182
 sock_hash_delete_elem+0x274/0x2f0 net/core/sock_map.c:941
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x248
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 ida_alloc_range+0x987/0xa80 lib/idr.c:460
 proc_alloc_inum+0x27/0x90 fs/proc/generic.c:206
 ns_alloc_inum include/linux/proc_ns.h:70 [inline]
 clone_uts_ns kernel/utsname.c:62 [inline]
 copy_utsname+0x1bb/0x440 kernel/utsname.c:100
 create_new_namespaces+0x171/0x670 kernel/nsproxy.c:84
 unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:226
 ksys_unshare+0x542/0xa00 kernel/fork.c:3168
 __do_sys_unshare kernel/fork.c:3242 [inline]
 __se_sys_unshare kernel/fork.c:3240 [inline]
 __x64_sys_unshare+0x38/0x40 kernel/fork.c:3240
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f7a773bbca9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7a7612f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f7a774e9f80 RCX: 00007f7a773bbca9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000064000600
RBP: 00007f7a7740747e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7a774e9f80 R15: 00007ffd59779638
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 21887 Comm: syz-executor.0 Not tainted 5.15.149-syzkaller-00490-g5d96939590c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc900013d76c0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff9200027aedc RCX: 1ffffffff0d1aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7137ed4
RBP: ffffc900013d7770 R08: dffffc0000000000 R09: ffffed103ee26fdb
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7137ed4 R14: 0000000000000001 R15: 1ffff9200027aee0
FS:  0000555555570480(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5fca9845e0 CR3: 00000001178db000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x41b/0xc40 kernel/locking/qspinlock.c:473
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x248
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 fscrypt_free_filename include/linux/fscrypt.h:320 [inline]
 ext4_fname_free_filename fs/ext4/ext4.h:2784 [inline]
 ext4_lookup_entry fs/ext4/namei.c:1773 [inline]
 ext4_lookup+0x3f3/0xaa0 fs/ext4/namei.c:1839
 lookup_one_qstr_excl+0x143/0x290 fs/namei.c:1563
 filename_create+0x28e/0x530 fs/namei.c:3836
 do_symlinkat+0xf4/0x5a0 fs/namei.c:4448
 __do_sys_symlinkat fs/namei.c:4475 [inline]
 __se_sys_symlinkat fs/namei.c:4472 [inline]
 __x64_sys_symlinkat+0x99/0xb0 fs/namei.c:4472
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f5fca900427
Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffc2133ff8 EFLAGS: 00000202 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 00007fffc21340c0 RCX: 00007f5fca900427
RDX: 00007f5fca94c52a RSI: 00000000ffffff9c RDI: 00007fffc21340c0
RBP: 0000000000000001 R08: 0000000000000017 R09: 00007fffc2133d47
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/05 08:21 android13-5.15-lts 5d96939590c0 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in sys_unshare
* Struck through repros no longer work on HEAD.