syzbot


INFO: rcu detected stall in blkdev_ioctl

Status: fixed on 2018/07/09 18:05
Reported-by: syzbot+369c35474963daf8f8eea897ecf33cb6ad6c7ea2@syzkaller.appspotmail.com
Fix commit: d2ac838e4cd7 loop: add recursion validation to LOOP_CHANGE_FD
First crash: 1824d, last: 1645d
duplicates (2):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
INFO: rcu detected stall in lo_compat_ioctl 27 1648d 1814d 24/24 closed as dup on 2018/05/04 17:05
INFO: rcu detected stall in lo_ioctl 193 1618d 1818d 0/24 closed as dup on 2018/05/04 17:09

Sample crash report:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
INFO: rcu_sched self-detected stall on CPU
	0-....: (124998 ticks this GP) idle=45e/1/4611686018427387906 softirq=9820/9820 fqs=31227 
	 (t=125000 jiffies g=4939 c=4938 q=43)
NMI backtrace for cpu 0
CPU: 0 PID: 4515 Comm: syz-executor699 Not tainted 4.17.0-rc2+ #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:156 [inline]
 rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1376
 print_cpu_stall kernel/rcu/tree.c:1525 [inline]
 check_cpu_stall.isra.61.cold.80+0x36c/0x59a kernel/rcu/tree.c:1593
 __rcu_pending kernel/rcu/tree.c:3356 [inline]
 rcu_pending kernel/rcu/tree.c:3401 [inline]
 rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763
 update_process_times+0x2d/0x70 kernel/time/timer.c:1636
 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:173
 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1283
 __run_hrtimer kernel/time/hrtimer.c:1386 [inline]
 __hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1448
 hrtimer_interrupt+0x286/0x650 kernel/time/hrtimer.c:1506
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline]
 smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:is_loop_device drivers/block/loop.c:713 [inline]
RIP: 0010:loop_set_fd drivers/block/loop.c:901 [inline]
RIP: 0010:lo_ioctl+0x1bb4/0x2130 drivers/block/loop.c:1397
RSP: 0018:ffff8801b37d7948 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff8801d2930d80 RCX: ffffffff84b2b784
RDX: 0000000000000007 RSI: 0000000000000007 RDI: 0000000000000005
RBP: ffff8801b37d79c0 R08: ffff8801b2d52500 R09: ffffed003b5c46c2
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000000
R13: ffff8801d4ff7418 R14: ffff8801b70936e0 R15: ffff8801b7093600
 __blkdev_driver_ioctl block/ioctl.c:303 [inline]
 blkdev_ioctl+0x9b6/0x2020 block/ioctl.c:601
 block_ioctl+0xee/0x130 fs/block_dev.c:1877
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x443e59
RSP: 002b:00007fff93b51bd8 EFLAGS: 00000217 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 6f6f6c2f7665642f RCX: 0000000000443e59
RDX: 0000000000000007 RSI: 0000000000004c00 RDI: 0000000000000008
RBP: 702f74656e2f666c R08: 00000000004002e0 R09: 00000000004002e0
R10: 0000000000000000 R11: 0000000000000217 R12: 65732f636f72702f
R13: 0000000000401b90 R14: 0000000000000000 R15: 0000000000000000

Crashes (249):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2018/04/27 23:48 upstream d8a332730e75 7785e404 .config log report syz C
ci-upstream-kasan-gce 2018/06/07 08:07 upstream 0ad39cb3d70f e0e534c6 .config log report
ci-upstream-kasan-gce 2018/06/07 06:10 upstream 0ad39cb3d70f e0e534c6 .config log report
ci-upstream-kasan-gce 2018/06/07 00:50 upstream 0ad39cb3d70f e0e534c6 .config log report
ci-upstream-kasan-gce 2018/06/06 19:59 upstream af6c5d5e01ad 41f9540d .config log report
ci-upstream-kasan-gce 2018/06/06 07:21 upstream 5037be168f0e 863a24bb .config log report
ci-upstream-kasan-gce 2018/06/06 03:38 upstream 5037be168f0e 863a24bb .config log report
ci-upstream-kasan-gce 2018/06/05 18:51 upstream 716a685fdb89 a316ff92 .config log report
ci-upstream-kasan-gce 2018/06/04 16:48 upstream 29dcea88779c 6cbe7c26 .config log report
ci-upstream-kasan-gce 2018/06/04 13:50 upstream 29dcea88779c 6cbe7c26 .config log report
ci-upstream-kasan-gce 2018/06/04 11:24 upstream 29dcea88779c 6cbe7c26 .config log report
ci-upstream-kasan-gce 2018/06/04 06:54 upstream 325e14f97e0c 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/04 05:52 upstream 325e14f97e0c 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/03 18:18 upstream 918fe1b31579 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/03 01:25 upstream 4277e6b9fd44 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/03 00:11 upstream 4277e6b9fd44 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/02 13:18 upstream 0512e0134582 2f93b54f .config log report
ci-upstream-kasan-gce 2018/06/02 01:48 upstream 0512e0134582 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/31 02:58 upstream d60d61f36b8f 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/30 16:44 upstream 0044cdeb7313 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/30 13:25 upstream 0044cdeb7313 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/30 12:10 upstream 0044cdeb7313 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/30 09:08 upstream 0044cdeb7313 2f93b54f .config log report
ci-upstream-kasan-gce-root 2018/05/30 07:41 upstream 0044cdeb7313 2f93b54f .config log report
ci-upstream-kasan-gce 2018/05/29 23:50 upstream 3d661e2a2d1c e276de77 .config log report
ci-upstream-kasan-gce 2018/05/29 20:00 upstream 3d661e2a2d1c e276de77 .config log report
ci-upstream-kasan-gce 2018/05/29 16:14 upstream 3d661e2a2d1c e276de77 .config log report
ci-upstream-kasan-gce 2018/05/29 13:03 upstream 786b71f5b754 e276de77 .config log report
ci-upstream-kasan-gce 2018/05/29 11:54 upstream 786b71f5b754 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/29 08:50 upstream 786b71f5b754 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/29 06:59 upstream 786b71f5b754 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/29 05:39 upstream 786b71f5b754 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/29 01:56 upstream 786b71f5b754 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/28 19:57 upstream b04e217704b7 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/28 18:41 upstream b04e217704b7 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/28 15:33 upstream b04e217704b7 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/28 12:57 upstream b04e217704b7 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/28 11:01 upstream b04e217704b7 f48c20b8 .config log report
ci-upstream-kasan-gce-root 2018/05/28 02:07 upstream 861d9dd37526 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/27 19:16 upstream 861d9dd37526 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/27 15:34 upstream 7fbb6157630f f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/27 12:02 upstream 7fbb6157630f f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/27 06:04 upstream 7fbb6157630f f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/26 17:40 upstream bc2dbc5420e8 f48c20b8 .config log report
ci-upstream-kasan-gce-root 2018/05/26 06:58 upstream 62d18ecfa641 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/26 03:34 upstream 62d18ecfa641 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/26 00:20 upstream 62d18ecfa641 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/25 11:15 upstream b50694381cfc f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/25 06:06 upstream d883c6cf3b39 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/24 20:12 upstream d883c6cf3b39 f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/24 14:17 upstream bee797529d7c f48c20b8 .config log report
ci-upstream-kasan-gce 2018/05/24 05:18 upstream bee797529d7c f48c20b8 .config log report
ci-upstream-kmsan-gce 2018/06/08 22:57 https://github.com/google/kmsan.git master d6c351f832e3 866118af .config log report
ci-upstream-kmsan-gce 2018/05/28 21:07 https://github.com/google/kmsan.git master 1b9cd4eccac9 f48c20b8 .config log report
ci-upstream-mmots-kasan-gce 2018/01/19 13:43 mmots 216435561218 161c1d64 .config log report
ci-upstream-next-kasan-gce 2018/01/16 17:15 linux-next fdddade65d7b 4198e588 .config log report
* Struck through repros no longer work on HEAD.