syzbot


INFO: rcu detected stall in sys_sendto (5)

Status: closed as invalid on 2022/02/08 10:00
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 430d, last: 309d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_sendto (2) 93 1063d 1063d 0/24 closed as dup on 2020/01/08 06:15
upstream INFO: rcu detected stall in sys_sendto 357 1098d 1099d 0/24 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in sys_sendto (4) 1 888d 888d 0/24 auto-closed as invalid on 2020/09/29 07:17
upstream INFO: rcu detected stall in sys_sendto (3) 1 966d 966d 0/24 closed as invalid on 2020/05/21 18:32

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10500 ticks this GP) idle=711/1/0x4000000000000000 softirq=26391/26391 fqs=5245 
	(t=10502 jiffies g=41649 q=912)
NMI backtrace for cpu 1
CPU: 1 PID: 7620 Comm: syz-executor.2 Not tainted 5.17.0-rc1-syzkaller-00436-g24f4db1f3a27 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x22d/0x390 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq+0x1e33/0x2bc0 kernel/rcu/tree.c:2617
 update_process_times+0x197/0x200 kernel/time/timer.c:1785
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:__rdmsr arch/x86/include/asm/msr.h:93 [inline]
RIP: 0010:native_read_msr arch/x86/include/asm/msr.h:127 [inline]
RIP: 0010:msr_read_counter arch/x86/events/msr.c:225 [inline]
RIP: 0010:msr_event_update+0xa5/0x1e0 arch/x86/events/msr.c:240
Code: 08 80 3c 28 00 74 08 4c 89 ff e8 66 0e cf 00 49 8b 2f 31 ff 48 89 ee e8 69 82 83 00 48 85 ed 74 34 e8 af 7d 83 00 89 e9 0f 32 <48> 89 d3 48 c1 e3 20 48 09 c3 66 90 eb 31 e8 98 7d 83 00 89 ef 48
RSP: 0018:ffffc90006d06b50 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880339fd1d0 RCX: 0000000000000034
RDX: 0000000000000000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 0000000000000034 R08: ffffffff810229d7 R09: ffffed100673fa77
R10: ffffed100673fa77 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880339fd3b0 R14: dffffc0000000000 R15: ffff8880339fd348
 perf_output_read_group kernel/events/core.c:6989 [inline]
 perf_output_read+0xebf/0x13b0 kernel/events/core.c:7028
 perf_output_sample+0x338/0x23e0 kernel/events/core.c:7075
 __perf_event_output kernel/events/core.c:7560 [inline]
 perf_event_output_forward+0x1e1/0x2c0 kernel/events/core.c:7574
 __perf_event_overflow+0x1f8/0x380 kernel/events/core.c:9274
 do_perf_sw_event kernel/events/core.c:9491 [inline]
 ___perf_sw_event+0x465/0x640 kernel/events/core.c:9522
 __perf_sw_event+0x13f/0x270 kernel/events/core.c:9534
 handle_mm_fault+0x2eef/0x39e0 mm/memory.c:4817
 do_user_addr_fault+0x8c4/0x1060 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1484 [inline]
 exc_page_fault+0xa1/0x1e0 arch/x86/mm/fault.c:1540
 asm_exc_page_fault+0x1e/0x30
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 0f 82 60 ff ff ff 89 d1 <f3> a4 31 c0 0f 01 ca c3 89 ca eb 06 66 0f 1f 44 00 00 83 f8 12 74
RSP: 0018:ffffc90006d078b8 EFLAGS: 00050206
RAX: ffffffff84119801 RBX: ffff888033b50000 RCX: 0000000000006fcb
RDX: 0000000000008000 RSI: 0000000020f4e000 RDI: ffff888033b51035
RBP: ffffc90006d07a10 R08: dffffc0000000000 R09: ffffed100676b000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000008000
R13: 00007ffffffff000 R14: 0000000020f4cfcb R15: ffffc90006d07e68
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 copyin lib/iov_iter.c:166 [inline]
 _copy_from_iter+0x33c/0x1170 lib/iov_iter.c:765
 copy_from_iter include/linux/uio.h:171 [inline]
 copy_from_iter_full include/linux/uio.h:177 [inline]
 skb_do_copy_data_nocache include/net/sock.h:2189 [inline]
 skb_copy_to_page_nocache include/net/sock.h:2215 [inline]
 tcp_sendmsg_locked+0x1bed/0x48a0 net/ipv4/tcp.c:1335
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1441
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 __sys_sendto+0x42e/0x5b0 net/socket.c:2040
 __do_sys_sendto net/socket.c:2052 [inline]
 __se_sys_sendto net/socket.c:2048 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2048
 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: 0033:0x7f23e598e059
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f23e4303168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f23e5aa0f60 RCX: 00007f23e598e059
RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006
RBP: 00007f23e59e808d R08: 0000000000000000 R09: 0000000000000053
R10: 0000000011000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffff106fecf R14: 00007f23e4303300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	08 80 3c 28 00 74    	or     %al,0x7400283c(%rax)
   6:	08 4c 89 ff          	or     %cl,-0x1(%rcx,%rcx,4)
   a:	e8 66 0e cf 00       	callq  0xcf0e75
   f:	49 8b 2f             	mov    (%r15),%rbp
  12:	31 ff                	xor    %edi,%edi
  14:	48 89 ee             	mov    %rbp,%rsi
  17:	e8 69 82 83 00       	callq  0x838285
  1c:	48 85 ed             	test   %rbp,%rbp
  1f:	74 34                	je     0x55
  21:	e8 af 7d 83 00       	callq  0x837dd5
  26:	89 e9                	mov    %ebp,%ecx
  28:	0f 32                	rdmsr
* 2a:	48 89 d3             	mov    %rdx,%rbx <-- trapping instruction
  2d:	48 c1 e3 20          	shl    $0x20,%rbx
  31:	48 09 c3             	or     %rax,%rbx
  34:	66 90                	xchg   %ax,%ax
  36:	eb 31                	jmp    0x69
  38:	e8 98 7d 83 00       	callq  0x837dd5
  3d:	89 ef                	mov    %ebp,%edi
  3f:	48                   	rex.W

Crashes (7):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-smack-root 2022/01/31 01:13 upstream 24f4db1f3a27 495e00c5 .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2022/01/14 06:19 upstream 455e73a07f6e b8d780ab .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2022/01/13 01:56 upstream f079ab01b560 44d1319a .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2021/12/05 07:41 upstream 79a72162048e a617004c .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2021/11/22 03:38 upstream 40c93d7fff6f 4eb20a4e .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2021/10/26 15:23 upstream 3906fe9bb7f1 d50eb50a .config log report info INFO: rcu detected stall in sys_sendto
ci-upstream-kasan-gce-smack-root 2021/10/02 04:42 upstream 53d5fc89d66a db0f5787 .config log report info INFO: rcu detected stall in sys_sendto
* Struck through repros no longer work on HEAD.