On Tue, Jul 10, 2018 at 10:08 AM, syzbot <syzbot+3a0570f93c0d6ca388f5@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: d00d6d9a339d Add linux-next specific files for 20180709 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=17fdd90c400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=94fe2b586beccacd > dashboard link: https://syzkaller.appspot.com/bug?extid=3a0570f93c0d6ca388f5 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > > Unfortunately, I don't have any reproducer for this crash yet. > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+3a0570f93c0d6ca388f5@xxxxxxxxxxxxxxxxxxxxxxxxx Look similar to the other hangs in 9p, this time caused by the following program: 21:30:55 executing program 0: pipe2$9p(&(0x7f0000000100)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x0) write$P9_RUNLINKAT(r1, &(0x7f0000000040)={0xffffffffffffffca, 0x4d}, 0x7) mkdir(&(0x7f0000000300)='./file0\x00', 0x0) mount$9p_fd(0x0, &(0x7f00000000c0)='./file0\x00', &(0x7f0000000340)='9p\x00', 0x0, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c}) write$P9_RREADDIR(r1, &(0x7f0000000480)={0x2a, 0x29, 0x1, {0x0, [{{}, 0x0, 0x0, 0x7, './file0'}]}}, 0x2a) write$P9_RGETATTR(r1, &(0x7f0000000200)={0xa0, 0x19, 0x1}, 0xa0) write$P9_RWALK(r1, &(0x7f0000000500)=ANY=[@ANYBLOB="090100006f01000000"], 0x9) mount$9p_fd(0x0, &(0x7f0000000080)='./file0\x00', &(0x7f0000000900)='9p\x00', 0x0, &(0x7f0000000840)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@access_uid={'access', 0x3d}, 0x2c}]}}) r2 = socket$inet6(0xa, 0x1000000000002, 0x0) ioctl(r2, 0x8912, &(0x7f0000000280)="025cc83d6d345f8f762070") utimes(&(0x7f0000000180)='./file0\x00', &(0x7f0000000380)) > 9pnet_virtio: no channels available for device (null) > Unknown ioctl 44801 > 9pnet_virtio: no channels available for device (null) > 9pnet: Insufficient options for proto=fd > 9pnet: Insufficient options for proto=fd > INFO: task syz-executor0:12044 blocked for more than 140 seconds. > Not tainted 4.18.0-rc3-next-20180709+ #2 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > syz-executor0 D25408 12044 4539 0x00000004 > Call Trace: > context_switch kernel/sched/core.c:2853 [inline] > __schedule+0x87c/0x1ed0 kernel/sched/core.c:3501 > schedule+0xfb/0x450 kernel/sched/core.c:3545 > __rwsem_down_write_failed_common+0x95d/0x1630 > kernel/locking/rwsem-xadd.c:566 > rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 > call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 > __down_write arch/x86/include/asm/rwsem.h:142 [inline] > down_write+0xaa/0x130 kernel/locking/rwsem.c:72 > inode_lock include/linux/fs.h:748 [inline] > utimes_common.isra.1+0x45c/0x8e0 fs/utimes.c:90 > do_utimes+0x1f7/0x380 fs/utimes.c:156 > do_futimesat+0x249/0x350 fs/utimes.c:212 > __do_sys_utimes fs/utimes.c:225 [inline] > __se_sys_utimes fs/utimes.c:222 [inline] > __x64_sys_utimes+0x59/0x80 fs/utimes.c:222 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x455e29 > Code: cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 0f 86 ab 04 00 00 48 83 ec > 58 48 89 6c 24 50 48 8d 6c 24 50 48 8b 44 24 60 c6 00 00 <48> 8b 4c 24 68 48 > 89 ca 48 89 50 08 48 8b 59 20 48 01 da 31 db 31 > RSP: 002b:00007fac7c8b4c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000eb > RAX: ffffffffffffffda RBX: 00007fac7c8b56d4 RCX: 0000000000455e29 > RDX: 0000000000000000 RSI: 0000000020000380 RDI: 0000000020000180 > RBP: 000000000072bff0 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff > R13: 00000000004c2af0 R14: 00000000004d4600 R15: 0000000000000002 > INFO: lockdep is turned off. > NMI backtrace for cpu 1 > CPU: 1 PID: 898 Comm: khungtaskd Not tainted 4.18.0-rc3-next-20180709+ #2 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 > nmi_cpu_backtrace.cold.5+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_all_cpu_backtrace include/linux/nmi.h:143 [inline] > check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] > watchdog+0xb39/0x10b0 kernel/hung_task.c:265 > kthread+0x345/0x410 kernel/kthread.c:246 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 > Sending NMI from CPU 1 to CPUs 0: > NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 > arch/x86/include/asm/irqflags.h:54 > > > --- > This bug is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/0000000000000bafc80570a0a1db%40google.com. > For more options, visit https://groups.google.com/d/optout.
