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-8,10.128.15.215' (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 syzkaller login: [ 32.052265] [ 32.055299] ============================= [ 32.059397] WARNING: suspicious RCU usage [ 32.062284] 4.13.0-rc6+ #48 Not tainted [ 32.062913] ----------------------------- [ 32.065202] ./include/linux/kvm_host.h:481 suspicious rcu_dereference_check() usage! [ 32.070184] [ 32.070184] other info that might help us debug this: [ 32.070184] [ 32.075068] [ 32.075068] rcu_scheduler_active = 2, debug_locks = 1 [ 32.087905] no locks held by syzkaller171020/3825. [ 32.093203] [ 32.093203] stack backtrace: executing program executing program executing program executing program [ 32.098054] CPU: 0 PID: 3825 Comm: syzkaller171020 Not tainted 4.13.0-rc6+ #48 [ 32.105387] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.115404] Call Trace: [ 32.117964] dump_stack+0x194/0x257 [ 32.121562] ? arch_local_irq_restore+0x53/0x53 [ 32.126212] lockdep_rcu_suspicious+0x123/0x170 [ 32.130854] kvm_dev_ioctl+0x877/0x1840 [ 32.134797] ? lock_downgrade+0x990/0x990 [ 32.138923] ? install_new_memslots+0x420/0x420 [ 32.143578] ? avc_has_extended_perms+0x7fa/0x12c0 [ 32.148475] ? find_held_lock+0x35/0x1d0 executing program executing program executing program [ 32.152514] ? avc_ss_reset+0x110/0x110 [ 32.156458] ? lock_downgrade+0x990/0x990 [ 32.160605] ? lock_release+0xa40/0xa40 [ 32.164553] ? __lock_is_held+0xb6/0x140 [ 32.168610] ? check_same_owner+0x320/0x320 [ 32.172915] ? install_new_memslots+0x420/0x420 [ 32.177818] do_vfs_ioctl+0x1b1/0x1520 [ 32.181692] ? ioctl_preallocate+0x2b0/0x2b0 [ 32.186072] ? selinux_capable+0x40/0x40 [ 32.190104] ? lock_release+0x1d1/0xa40 [ 32.194056] ? syscall_return_slowpath+0x22f/0x450 executing program [ 32.198962] ? security_file_ioctl+0x7d/0xb0 [ 32.203338] ? security_file_ioctl+0x89/0xb0 [ 32.207720] SyS_ioctl+0x8f/0xc0 [ 32.211060] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 32.215786] RIP: 0033:0x446209 [ 32.218944] RSP: 002b:00007fd99059bdc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 32.226634] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446209 [ 32.233873] RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 [ 32.241114] RBP: 0000000000000086 R08: 00007fd99059c700 R09: 00007fd99059c700 executing program executing program executing program executing program executing program executing program [ 32.248352] R10: 00007fd99059c700 R11: 0000000000000246 R12: 0000000000000000 [ 32.255590] R13: 00007fff79a7408f R14: 00007fd99059c9c0 R15: 0000000000000000 [ 32.262990] [ 32.265717] ============================= [ 32.270139] WARNING: suspicious RCU usage [ 32.275874] 4.13.0-rc6+ #48 Not tainted [ 32.280985] ----------------------------- [ 32.285654] ./include/linux/kvm_host.h:575 suspicious rcu_dereference_check() usage! [ 32.298432] executing program executing program executing program [ 32.298432] other info that might help us debug this: [ 32.298432] [ 32.309650] [ 32.309650] rcu_scheduler_active = 2, debug_locks = 1 [ 32.323417] no locks held by syzkaller171020/3825. [ 32.329274] [ 32.329274] stack backtrace: [ 32.334620] CPU: 0 PID: 3825 Comm: syzkaller171020 Not tainted 4.13.0-rc6+ #48 [ 32.341963] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 executing program [ 32.351286] Call Trace: [ 32.353853] dump_stack+0x194/0x257 [ 32.357452] ? arch_local_irq_restore+0x53/0x53 [ 32.362113] lockdep_rcu_suspicious+0x123/0x170 [ 32.366759] kvm_dev_ioctl+0xd21/0x1840 [ 32.370704] ? lock_downgrade+0x990/0x990 [ 32.374832] ? install_new_memslots+0x420/0x420 [ 32.379488] ? avc_has_extended_perms+0x7fa/0x12c0 [ 32.384385] ? find_held_lock+0x35/0x1d0 [ 32.388432] ? avc_ss_reset+0x110/0x110 [ 32.392372] ? lock_downgrade+0x990/0x990 [ 32.396491] ? lock_release+0xa40/0xa40 executing program [ 32.400436] ? __lock_is_held+0xb6/0x140 [ 32.404493] ? check_same_owner+0x320/0x320 [ 32.408796] ? install_new_memslots+0x420/0x420 [ 32.413435] do_vfs_ioctl+0x1b1/0x1520 [ 32.417297] ? ioctl_preallocate+0x2b0/0x2b0 [ 32.421687] ? selinux_capable+0x40/0x40 [ 32.425731] ? lock_release+0x1d1/0xa40 [ 32.429684] ? syscall_return_slowpath+0x22f/0x450 [ 32.434589] ? security_file_ioctl+0x7d/0xb0 [ 32.438965] ? security_file_ioctl+0x89/0xb0 [ 32.443345] SyS_ioctl+0x8f/0xc0 [ 32.446687] entry_SYSCALL_64_fastpath+0x1f/0xbe executing program executing program executing program executing program executing program executing program executing program executing program [ 32.451409] RIP: 0033:0x446209 [ 32.454568] RSP: 002b:00007fd99059bdc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 32.462245] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446209 [ 32.469481] RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 [ 32.476719] RBP: 0000000000000086 R08: 00007fd99059c700 R09: 00007fd99059c700 [ 32.483956] R10: 00007fd99059c700 R11: 0000000000000246 R12: 0000000000000000 [ 32.491205] R13: 00007fff79a7408f R14: 00007fd99059c9c0 R15: 0000000000000000 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