syzbot


INFO: rcu detected stall in sys_symlink (4)

Status: closed as invalid on 2022/02/08 09:50
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 420d, last: 316d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_symlink (3) 4 1053d 1053d 0/24 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_symlink (2) 2 1053d 1053d 0/24 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_symlink 17 1088d 1089d 0/24 closed as invalid on 2019/12/04 14:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P1584/1:b..l
	(detected by 1, t=10502 jiffies, g=207021, q=126)
task:syz-executor.1  state:R  running task     stack:27568 pid: 1584 ppid: 30043 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0x971/0x10e0 kernel/sched/core.c:6296
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6711
 irqentry_exit+0x56/0x90 kernel/entry/common.c:425
 asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:196
Code: 84 00 00 00 00 00 0f 1f 40 00 be 0d 00 00 00 48 c7 c7 60 bd b5 8c e8 ff 5c 4b 00 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0c 25 c0 6f 02 00 65 8b 15 14 c9 7d 7e f7 c2
RSP: 0018:ffffc9000413f618 EFLAGS: 00000283
RAX: 0000000000000001 RBX: 00007fef8e6778f7 RCX: ffff888075500000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8cb1e380
RBP: 0000000000000001 R08: ffffffff810090a9 R09: ffffc9000413f7b0
R10: fffff52000827ee4 R11: 0000000000000000 R12: ffff888075500000
R13: ffffffff8171fb20 R14: 00007fef8e6778f7 R15: 1ffff92000827ee1
 rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:267
 rcu_read_lock include/linux/rcupdate.h:694 [inline]
 is_bpf_text_address+0x27/0x270 kernel/bpf/core.c:715
 kernel_text_address+0x9e/0xd0 kernel/extable.c:124
 __kernel_text_address+0x9/0x40 kernel/extable.c:78
 unwind_get_return_address+0x48/0x80 arch/x86/kernel/unwind_orc.c:318
 arch_stack_walk+0xf8/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x11b/0x1e0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:516
 kasan_kmalloc include/linux/kasan.h:270 [inline]
 kmem_cache_alloc_trace+0x9d/0x330 mm/slub.c:3257
 kmalloc include/linux/slab.h:582 [inline]
 kzalloc include/linux/slab.h:716 [inline]
 smk_fetch security/smack/smack_lsm.c:290 [inline]
 smack_d_instantiate+0x65d/0xd10 security/smack/smack_lsm.c:3416
 security_d_instantiate+0xa5/0x100 security/security.c:2032
 d_instantiate_new+0x61/0x110 fs/dcache.c:2027
 ext4_add_nondir+0x22b/0x290 fs/ext4/namei.c:2714
 ext4_symlink+0x9a8/0xfa0 fs/ext4/namei.c:3363
 vfs_symlink+0x246/0x3d0 fs/namei.c:4249
 do_symlinkat+0x22c/0x650 fs/namei.c:4278
 __do_sys_symlink fs/namei.c:4300 [inline]
 __se_sys_symlink fs/namei.c:4298 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4298
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fef8e6778f7
RSP: 002b:00007ffc51402d38 EFLAGS: 00000202 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fef8e6778f7
RDX: 00007ffc51402e13 RSI: 00007fef8e6d214f RDI: 00007ffc51402e00
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc51402bd0
R10: 00007ffc51402a87 R11: 0000000000000202 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffc51402e00
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g207021 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=86928
rcu: rcu_preempt kthread starved for 10502 jiffies! g207021 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26576 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0x971/0x10e0 kernel/sched/core.c:6296
 schedule+0x12b/0x1f0 kernel/sched/core.c:6369
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x1fd/0x770 kernel/rcu/tree.c:1963
 rcu_gp_kthread+0xa5/0x350 kernel/rcu/tree.c:2136
 kthread+0x468/0x490 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 27927 Comm: kworker/u4:8 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:idr_find+0xe/0x60 lib/idr.c:174
Code: 07 80 c1 03 38 c1 7c de e8 2f 4f 8a fd eb d7 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41 56 53 49 89 f6 48 89 fb e8 62 e6 3e fd <48> 8d 7b 50 48 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 8a
RSP: 0018:ffffc90004ce7b18 EFLAGS: 00000293
RAX: ffffffff8445c03e RBX: ffff88807a106000 RCX: ffff88801e658000
RDX: 0000000000000000 RSI: ffffffffcc03b295 RDI: ffff88807a106000
RBP: ffff88807804dc00 R08: ffffffff8446b09a R09: 0000000000000003
R10: fffff5200099cf55 R11: 0000000000000004 R12: ffff88807a106000
R13: ffff88807a106058 R14: ffffffffcc03b295 R15: ffff88807a106098
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f841f75b000 CR3: 000000006541d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tipc_topsrv_stop net/tipc/topsrv.c:691 [inline]
 tipc_topsrv_exit_net+0xdb/0x310 net/tipc/topsrv.c:715
 ops_exit_list net/core/net_namespace.c:168 [inline]
 cleanup_net+0x758/0xc50 net/core/net_namespace.c:595
 process_one_work+0x850/0x1130 kernel/workqueue.c:2307
 worker_thread+0xab1/0x1300 kernel/workqueue.c:2454
 kthread+0x468/0x490 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30
 </TASK>
----------------
Code disassembly (best guess):
   0:	84 00                	test   %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	00 00                	add    %al,(%rax)
   6:	0f 1f 40 00          	nopl   0x0(%rax)
   a:	be 0d 00 00 00       	mov    $0xd,%esi
   f:	48 c7 c7 60 bd b5 8c 	mov    $0xffffffff8cb5bd60,%rdi
  16:	e8 ff 5c 4b 00       	callq  0x4b5d1a
  1b:	c3                   	retq
  1c:	cc                   	int3
  1d:	cc                   	int3
  1e:	cc                   	int3
  1f:	cc                   	int3
  20:	cc                   	int3
  21:	cc                   	int3
  22:	cc                   	int3
  23:	cc                   	int3
  24:	cc                   	int3
  25:	cc                   	int3
  26:	cc                   	int3
  27:	cc                   	int3
  28:	cc                   	int3
  29:	cc                   	int3
* 2a:	48 8b 04 24          	mov    (%rsp),%rax <-- trapping instruction
  2e:	65 48 8b 0c 25 c0 6f 	mov    %gs:0x26fc0,%rcx
  35:	02 00
  37:	65 8b 15 14 c9 7d 7e 	mov    %gs:0x7e7dc914(%rip),%edx        # 0x7e7dc952
  3e:	f7                   	.byte 0xf7
  3f:	c2                   	.byte 0xc2

Crashes (11):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-smack-root 2022/01/14 02:59 upstream 455e73a07f6e b8d780ab .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-root 2021/12/28 01:14 upstream a8ad9a2434dc 6b3c5e64 .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-smack-root 2021/12/14 01:58 upstream 5472f14a3742 5d14b1ea .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-smack-root 2021/10/23 10:02 upstream 9c0c4d24ac00 282f03fb .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-selinux-root 2021/10/23 09:38 upstream 9c0c4d24ac00 282f03fb .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-root 2021/10/21 08:44 upstream 8e37395c3a5d f111d03b .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-root 2021/10/07 00:30 upstream 60a9483534ed 62ee0987 .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-smack-root 2021/10/03 02:19 upstream ab2a7a35c4e7 db0f5787 .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-smack-root 2021/10/01 20:41 upstream 24f67d82c43c cc80db95 .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-net-kasan-gce 2021/11/19 23:28 net-next 812ad3d270cb 3a9d0024 .config log report info INFO: rcu detected stall in sys_symlink
ci-upstream-kasan-gce-root 2021/12/22 22:47 upstream 3f066e882bf1 6caa12e4 .config log report info BUG: soft lockup in sys_symlink
* Struck through repros no longer work on HEAD.