On Thu, Mar 29, 2018 at 6:53 PM, Dmitry Vyukov <dvyu...@google.com> wrote: > On Thu, Mar 29, 2018 at 6:32 PM, Steven Rostedt <rost...@goodmis.org> wrote: >> >> Not sure why we are being Cc'd on this crash. >> >> On Thu, 29 Mar 2018 09:01:02 -0700 >> syzbot <syzbot+d1fe9b7b917f2715c...@syzkaller.appspotmail.com> wrote: >> >>> Hello, >>> >>> syzbot hit the following crash on upstream commit >>> bcfc1f4554662d8f2429ac8bd96064a59c149754 (Sat Mar 24 16:50:12 2018 +0000) >>> Merge tag 'pinctrl-v4.16-3' of >>> git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl >>> syzbot dashboard link: >>> https://syzkaller.appspot.com/bug?extid=d1fe9b7b917f2715c7d4 >>> >>> syzkaller reproducer: >>> https://syzkaller.appspot.com/x/repro.syz?id=4649457446551552 >>> Raw console output: >>> https://syzkaller.appspot.com/x/log.txt?id=4909621332410368 >>> Kernel config: >>> https://syzkaller.appspot.com/x/.config?id=-5034017172441945317 >>> compiler: gcc (GCC) 7.1.1 20170620 >>> >>> IMPORTANT: if you fix the bug, please add the following tag to the commit: >>> Reported-by: syzbot+d1fe9b7b917f2715c...@syzkaller.appspotmail.com >>> It will help syzbot understand when the bug is fixed. See footer for >>> details. >>> If you forward the report, please keep this part and the footer. >>> >>> IPVS: ftp: loaded support on port[0] = 21 >>> kasan: CONFIG_KASAN_INLINE enabled >>> kasan: GPF could be caused by NULL-ptr deref or user memory access >>> kasan: CONFIG_KASAN_INLINE enabled >>> kasan: GPF could be caused by NULL-ptr deref or user memory access >>> general protection fault: 0000 [#1] SMP KASAN >>> Dumping ftrace buffer: >>> (ftrace buffer empty) >>> Modules linked in: >>> CPU: 0 PID: 4170 Comm: syz-executor0 Not tainted 4.16.0-rc6+ #1 >>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS >>> Google 01/01/2011 >>> RIP: 0010:__lock_acquire+0x209/0x3e00 kernel/locking/lockdep.c:3320 >> >> Something is totally messed up here if you took a GPF in lockdep itself. >> >>> RSP: 0018:ffff8801db206f60 EFLAGS: 00010002 >>> RAX: 078e0401078e0401 RBX: 0000000000000000 RCX: 0000000000000000 >>> RDX: 1ffff100389fe583 RSI: 0000000000000000 RDI: ffff8801c4ff2c18 >>> RBP: ffff8801db2072f0 R08: ffffffff814d839c R09: 0000000000000001 >>> R10: 0000000000000000 R11: ffff8801c4ff2c10 R12: 0000000000000000 >>> R13: 0000000000000001 R14: 0000000000000000 R15: ffff8801b793c440 >>> FS: 00000000014fa940(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 >>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>> CR2: 00000000004cb4e0 CR3: 00000001b7980002 CR4: 00000000001606f0 >>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >>> Call Trace: >>> <IRQ> >>> lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 >>> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] >>> _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152 >>> try_to_wake_up+0xbc/0x15f0 kernel/sched/core.c:1989 >>> default_wake_function+0x30/0x50 kernel/sched/core.c:3693 >>> autoremove_wake_function+0x78/0x350 kernel/sched/wait.c:377 >>> __wake_up_common+0x18e/0x780 kernel/sched/wait.c:97 >>> __wake_up_common_lock+0x1b4/0x310 kernel/sched/wait.c:125 >>> __wake_up+0xe/0x10 kernel/sched/wait.c:149 >>> wake_up_klogd_work_func+0x4a/0x70 kernel/printk/printk.c:2869 >>> irq_work_run_list+0x184/0x240 kernel/irq_work.c:155 >>> irq_work_tick+0x136/0x1a0 kernel/irq_work.c:181 >>> update_process_times+0x48/0x60 kernel/time/timer.c:1639 >>> tick_sched_handle+0x85/0x160 kernel/time/tick-sched.c:162 >>> tick_sched_timer+0x42/0x120 kernel/time/tick-sched.c:1194 >>> __run_hrtimer kernel/time/hrtimer.c:1349 [inline] >>> __hrtimer_run_queues+0x39c/0xec0 kernel/time/hrtimer.c:1411 >>> hrtimer_interrupt+0x2a5/0x6f0 kernel/time/hrtimer.c:1469 >>> local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] >>> smp_apic_timer_interrupt+0x14a/0x700 arch/x86/kernel/apic/apic.c:1050 >>> apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:857 >>> </IRQ> >>> RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:778 >>> [inline] >>> RIP: 0010:console_unlock+0xb18/0xfb0 kernel/printk/printk.c:2403 >> >> Perhaps this is the reason we are being Cc'd? >> >> But this looks to be a side-effect of the first bug. If your box is >> crashing within lockdep, I'm betting the system is hosed, and you will >> get crashes in random locations after that. >> >> I doubt this is a printk issue. > > Hi Steven, > > You were CCed because this crash was attributed to > kernel/printk/printk.c (higher frames are in very common code, and > these are skipped for the purpose of bug attribution). > > The box was perfectly fine before running the provided reproducer, the > kernel is not tainted and nothing was executed before this program > (except for common init code). > > +Eric, from the reproducer this looks like the known bug in tun. Is > there any progress on that bug, it seems to cause a bunch of assorted > crashes.
#syz fix: vlan: Fix vlan insertion for packets without ethernet header >>> RSP: 0018:ffff8801b79068d8 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff12 >>> RAX: ffff8801b793c440 RBX: 0000000000000200 RCX: ffffffff815a8d6f >>> RDX: 0000000000000000 RSI: 1ffff10036f279af RDI: 0000000000000293 >>> RBP: ffff8801b7906a40 R08: 1ffff10036f20ce9 R09: 0000000000000000 >>> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 >>> R13: 0000000000000000 R14: ffffffff83ba15e0 R15: dffffc0000000000 >>> vprintk_emit+0x5c3/0xb90 kernel/printk/printk.c:1907 >>> vprintk_default+0x28/0x30 kernel/printk/printk.c:1947 >>> vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379 >>> printk+0xaa/0xca kernel/printk/printk.c:1980 >>> kasan_die_handler+0x3d/0x3f arch/x86/mm/kasan_init_64.c:248 >>> notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93 >>> __atomic_notifier_call_chain kernel/notifier.c:183 [inline] >>> atomic_notifier_call_chain+0x77/0x140 kernel/notifier.c:193 >>> notify_die+0x18c/0x280 kernel/notifier.c:549 >>> do_general_protection+0x331/0x3e0 arch/x86/kernel/traps.c:558 >>> general_protection+0x25/0x50 arch/x86/entry/entry_64.S:1150 >>> RIP: 0010:find_entry.isra.14+0x9f/0x1d0 fs/proc/proc_sysctl.c:119 >>> RSP: 0018:ffff8801b7906fc8 EFLAGS: 00010202 >>> RAX: 00f1c08020f1c080 RBX: ffff8801c4f95058 RCX: ffffffff81d29eae >>> RDX: 0000000000000000 RSI: ffff8801b8991678 RDI: ffff8801c4f95070 >>> RBP: ffff8801b7907008 R08: 1ffff10036f20d55 R09: 0000000000000004 >>> R10: ffff8801b7906f70 R11: 0000000000000000 R12: ffff8801b89915f8 >>> R13: dffffc0000000000 R14: 078e0401078e0401 R15: ffff8801b8991678 >>> find_subdir+0xa8/0x170 fs/proc/proc_sysctl.c:923 >>> get_subdir fs/proc/proc_sysctl.c:977 [inline] >>> __register_sysctl_table+0x6d5/0x10b0 fs/proc/proc_sysctl.c:1327 >>> register_net_sysctl+0x29/0x30 net/sysctl_net.c:120 >>> mpls_dev_sysctl_register+0x1cf/0x2e0 net/mpls/af_mpls.c:1369 >>> mpls_add_dev net/mpls/af_mpls.c:1420 [inline] >>> mpls_dev_notify+0x2af/0x980 net/mpls/af_mpls.c:1542 >>> notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93 >>> __raw_notifier_call_chain kernel/notifier.c:394 [inline] >>> raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 >>> call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707 >>> call_netdevice_notifiers net/core/dev.c:1725 [inline] >>> register_netdevice+0xd40/0x1020 net/core/dev.c:7929 >>> register_netdev+0x1a/0x30 net/core/dev.c:8014 >>> sit_init_net+0x384/0xa70 net/ipv6/sit.c:1852 >>> ops_init+0x10a/0x570 net/core/net_namespace.c:118 >>> setup_net+0x351/0x760 net/core/net_namespace.c:302 >>> copy_net_ns+0x238/0x580 net/core/net_namespace.c:426 >>> create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107 >>> unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206 >>> SYSC_unshare kernel/fork.c:2407 [inline] >>> SyS_unshare+0x653/0xfa0 kernel/fork.c:2357 >>> do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 >>> entry_SYSCALL_64_after_hwframe+0x42/0xb7 >>> RIP: 0033:0x457327 >>> RSP: 002b:00007ffdd0bf1928 EFLAGS: 00000202 ORIG_RAX: 0000000000000110 >>> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000457327 >>> RDX: 0000000000000000 RSI: 00007ffdd0bf1900 RDI: 0000000040000000 >>> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 >>> R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000410710 >>> R13: 00000000004107a0 R14: 0000000000000000 R15: 0000000000000000 >>> Code: 48 85 c0 4c 8b 9d e8 fc ff ff 8b 8d e0 fc ff ff 44 8b 8d d8 fc ff ff >>> 4c 8b 85 d0 fc ff ff 44 8b 95 c8 fc ff ff 0f 84 9b 07 00 00 <f0> ff 80 38 >>> 01 00 00 49 8d bf 70 08 00 00 48 ba 00 00 00 00 00 >>> RIP: __lock_acquire+0x209/0x3e00 kernel/locking/lockdep.c:3320 RSP: >>> ffff8801db206f60 >>> ---[ end trace b962f2b4a8ee2930 ]--- >>> >>> >>> --- >>> This bug is generated by a dumb bot. It may contain errors. >>> See https://goo.gl/tpsmEJ for details. >>> Direct all questions to syzkal...@googlegroups.com. >>> >>> syzbot will keep track of this bug report. >>> If you forgot to add the Reported-by tag, once the fix for this bug is >>> merged >>> into any tree, please reply to this email with: >>> #syz fix: exact-commit-title >>> If you want to test a patch for this bug, please reply with: >>> #syz test: git://repo/address.git branch >>> and provide the patch inline or as an attachment. >>> To mark this as a duplicate of another syzbot report, please reply with: >>> #syz dup: exact-subject-of-another-report >>> If it's a one-off invalid bug report, please reply with: >>> #syz invalid >>> Note: if the crash happens again, it will cause creation of a new bug >>> report. >>> Note: all commands must start from beginning of the line in the email body. >> >> -- >> 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+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/syzkaller-bugs/20180329123225.3a8fd6f5%40gandalf.local.home. >> For more options, visit https://groups.google.com/d/optout.
