INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added 'ci-upstream-kasan-gce-0,10.128.0.13' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 175.085105] [ 175.085466] ============================= [ 175.086236] WARNING: suspicious RCU usage [ 175.086806] 4.13.0-rc5+ #43 Not tainted [ 175.087394] ----------------------------- [ 175.087948] ./include/linux/kvm_host.h:481 suspicious rcu_dereference_check() usage! [ 175.089023] [ 175.089023] other info that might help us debug this: [ 175.089023] [ 175.090103] [ 175.090103] rcu_scheduler_active = 2, debug_locks = 1 [ 175.090978] no locks held by syzkaller338073/4359. [ 175.091662] [ 175.091662] stack backtrace: [ 175.092313] CPU: 0 PID: 4359 Comm: syzkaller338073 Not tainted 4.13.0-rc5+ #43 [ 175.093283] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 175.094530] Call Trace: [ 175.094889] dump_stack+0x194/0x257 [ 175.095381] ? arch_local_irq_restore+0x53/0x53 [ 175.096013] lockdep_rcu_suspicious+0x123/0x170 [ 175.096648] kvm_dev_ioctl+0x877/0x1840 [ 175.097178] ? lock_downgrade+0x990/0x990 [ 175.097757] ? install_new_memslots+0x420/0x420 [ 175.098393] ? avc_has_extended_perms+0x7fa/0x12c0 [ 175.099049] ? find_held_lock+0x35/0x1d0 [ 175.099618] ? avc_ss_reset+0x110/0x110 [ 175.100149] ? lock_downgrade+0x990/0x990 [ 175.100731] ? lock_release+0xa40/0xa40 [ 175.101286] ? __lock_is_held+0xb6/0x140 [ 175.101854] ? check_same_owner+0x320/0x320 [ 175.102492] ? install_new_memslots+0x420/0x420 [ 175.103114] do_vfs_ioctl+0x1b1/0x1520 [ 175.103660] ? ioctl_preallocate+0x2b0/0x2b0 [ 175.104254] ? selinux_capable+0x40/0x40 [ 175.104828] ? lock_downgrade+0x811/0x990 [ 175.106476] ? syscall_return_slowpath+0x22f/0x450 [ 175.111380] ? security_file_ioctl+0x7d/0xb0 [ 175.115754] ? security_file_ioctl+0x89/0xb0 [ 175.120136] SyS_ioctl+0x8f/0xc0 [ 175.123474] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 175.128198] RIP: 0033:0x446139 [ 175.131355] RSP: 002b:00007fae97c22dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 175.139028] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446139 [ 175.146265] RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 [ 175.153502] RBP: 0000000000000086 R08: 00007fae97c23700 R09: 00007fae97c23700 [ 175.160737] R10: 00007fae97c23700 R11: 0000000000000246 R12: 0000000000000000 [ 175.167976] R13: 00007ffec079e9af R14: 00007fae97c239c0 R15: 0000000000000000 [ 175.175307] [ 175.176919] ============================= [ 175.181056] WARNING: suspicious RCU usage [ 175.185195] 4.13.0-rc5+ #43 Not tainted [ 175.189153] ----------------------------- [ 175.193289] ./include/linux/kvm_host.h:575 suspicious rcu_dereference_check() usage! [ 175.201162] [ 175.201162] other info that might help us debug this: [ 175.201162] [ 175.209307] [ 175.209307] rcu_scheduler_active = 2, debug_locks = 1 [ 175.215976] no locks held by syzkaller338073/4359. [ 175.220902] [ 175.220902] stack backtrace: [ 175.225398] CPU: 0 PID: 4359 Comm: syzkaller338073 Not tainted 4.13.0-rc5+ #43 [ 175.232732] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 175.242054] Call Trace: [ 175.244614] dump_stack+0x194/0x257 [ 175.248237] ? arch_local_irq_restore+0x53/0x53 [ 175.252887] lockdep_rcu_suspicious+0x123/0x170 [ 175.257526] kvm_dev_ioctl+0xd21/0x1840 [ 175.261465] ? lock_downgrade+0x990/0x990 [ 175.265587] ? install_new_memslots+0x420/0x420 [ 175.270241] ? avc_has_extended_perms+0x7fa/0x12c0 [ 175.275137] ? find_held_lock+0x35/0x1d0 [ 175.279176] ? avc_ss_reset+0x110/0x110 [ 175.283120] ? lock_downgrade+0x990/0x990 [ 175.287242] ? lock_release+0xa40/0xa40 [ 175.291191] ? __lock_is_held+0xb6/0x140 [ 175.295248] ? check_same_owner+0x320/0x320 [ 175.299552] ? install_new_memslots+0x420/0x420 [ 175.304191] do_vfs_ioctl+0x1b1/0x1520 [ 175.308058] ? ioctl_preallocate+0x2b0/0x2b0 [ 175.312439] ? selinux_capable+0x40/0x40 [ 175.316469] ? lock_downgrade+0x811/0x990 [ 175.320598] ? syscall_return_slowpath+0x22f/0x450 [ 175.325501] ? security_file_ioctl+0x7d/0xb0 [ 175.329874] ? security_file_ioctl+0x89/0xb0 [ 175.334254] SyS_ioctl+0x8f/0xc0 [ 175.337591] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 175.342313] RIP: 0033:0x446139 [ 175.345468] RSP: 002b:00007fae97c22dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 175.353140] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446139 [ 175.360376] RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 [ 175.367616] RBP: 0000000000000086 R08: 00007fae97c23700 R09: 00007fae97c23700 [ 175.374852] R10: 00007fae97c23700 R11: 0000000000000246 R12: 0000000000000000 executing program [ 175.382097] R13: 00007ffec079e9af R14: 00007fae97c239c0 R15: 0000000000000000 executing program executing program executing program executing program executing program executing program executing program executing program