Starting OpenBSD Secure Shell server... [ OK ] Started Regular background program processing daemon. Starting System Logging Service... Starting Permit User Sessions... [ OK ] Found device /dev/ttyS0. [ 58.828074][ T8139] sshd (8139) used greatest stack depth: 22920 bytes left [ OK ] Started System Logging Service. [ OK ] Started Permit User Sessions. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.178' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 79.271778][ T35] audit: type=1400 audit(1609838860.914:8): avc: denied { execmem } for pid=8479 comm="syz-executor933" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 79.277029][ T8479] ================================================================== [ 79.300558][ T8479] BUG: KASAN: null-ptr-deref in bdi_put+0x22/0xa0 [ 79.307024][ T8479] Write of size 4 at addr 0000000000000040 by task syz-executor933/8479 [ 79.315353][ T8479] [ 79.317687][ T8479] CPU: 0 PID: 8479 Comm: syz-executor933 Not tainted 5.11.0-rc2-syzkaller #0 [ 79.326431][ T8479] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.336473][ T8479] Call Trace: [ 79.339740][ T8479] dump_stack+0x107/0x163 [ 79.344062][ T8479] ? bdi_put+0x22/0xa0 [ 79.348154][ T8479] ? bdi_put+0x22/0xa0 [ 79.352236][ T8479] kasan_report.cold+0x5f/0xd5 [ 79.356992][ T8479] ? bdi_put+0x22/0xa0 [ 79.361049][ T8479] check_memory_region+0x13d/0x180 [ 79.366150][ T8479] bdi_put+0x22/0xa0 [ 79.370033][ T8479] bdev_evict_inode+0x262/0x460 [ 79.374887][ T8479] ? __blkdev_direct_IO_simple+0x930/0x930 [ 79.380687][ T8479] evict+0x2ed/0x6b0 [ 79.384589][ T8479] iput.part.0+0x57e/0x810 [ 79.388993][ T8479] ? find_inode_nowait+0x190/0x190 [ 79.394094][ T8479] iput+0x58/0x70 [ 79.397724][ T8479] dentry_unlink_inode+0x2b1/0x3d0 [ 79.402839][ T8479] __dentry_kill+0x3c0/0x640 [ 79.407432][ T8479] ? dput+0x35/0xbc0 [ 79.411316][ T8479] ? dput+0x35/0xbc0 [ 79.415197][ T8479] dput+0x725/0xbc0 [ 79.418998][ T8479] shrink_dcache_for_umount+0x11f/0x330 [ 79.424531][ T8479] ? lockdep_hardirqs_on+0x79/0x100 [ 79.429735][ T8479] generic_shutdown_super+0x68/0x370 [ 79.435010][ T8479] kill_anon_super+0x36/0x60 [ 79.439588][ T8479] deactivate_locked_super+0x94/0x160 [ 79.444951][ T8479] deactivate_super+0xad/0xd0 [ 79.449621][ T8479] cleanup_mnt+0x3a3/0x530 [ 79.454030][ T8479] task_work_run+0xdd/0x190 [ 79.458528][ T8479] exit_to_user_mode_prepare+0x249/0x250 [ 79.464151][ T8479] syscall_exit_to_user_mode+0x19/0x50 [ 79.469608][ T8479] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 79.475490][ T8479] RIP: 0033:0x440219 [ 79.479370][ T8479] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 79.499063][ T8479] RSP: 002b:00007ffe006d9e98 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 79.507470][ T8479] RAX: ffffffffffffffea RBX: 0030656c69662f2e RCX: 0000000000440219 [ 79.515425][ T8479] RDX: 00000000200001c0 RSI: 0000000020000300 RDI: 0000000000000000 [ 79.523383][ T8479] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 79.531341][ T8479] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a20 [ 79.539297][ T8479] R13: 0000000000401ab0 R14: 0000000000000000 R15: 0000000000000000 [ 79.547266][ T8479] ================================================================== [ 79.555325][ T8479] Disabling lock debugging due to kernel taint [ 79.561710][ T8479] Kernel panic - not syncing: panic_on_warn set ... [ 79.568305][ T8479] CPU: 0 PID: 8479 Comm: syz-executor933 Tainted: G B 5.11.0-rc2-syzkaller #0 [ 79.578465][ T8479] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.588517][ T8479] Call Trace: [ 79.591779][ T8479] dump_stack+0x107/0x163 [ 79.596096][ T8479] ? bdi_alloc+0xe0/0x140 [ 79.600415][ T8479] panic+0x306/0x73d [ 79.604308][ T8479] ? __warn_printk+0xf3/0xf3 [ 79.608899][ T8479] ? preempt_schedule_common+0x59/0xc0 [ 79.614341][ T8479] ? bdi_put+0x22/0xa0 [ 79.618391][ T8479] ? preempt_schedule_thunk+0x16/0x18 [ 79.623747][ T8479] ? trace_hardirqs_on+0x38/0x1c0 [ 79.628754][ T8479] ? trace_hardirqs_on+0x51/0x1c0 [ 79.633762][ T8479] ? bdi_put+0x22/0xa0 [ 79.637811][ T8479] ? bdi_put+0x22/0xa0 [ 79.641859][ T8479] end_report+0x58/0x5e [ 79.646000][ T8479] kasan_report.cold+0x67/0xd5 [ 79.650746][ T8479] ? bdi_put+0x22/0xa0 [ 79.654807][ T8479] check_memory_region+0x13d/0x180 [ 79.659903][ T8479] bdi_put+0x22/0xa0 [ 79.663787][ T8479] bdev_evict_inode+0x262/0x460 [ 79.668626][ T8479] ? __blkdev_direct_IO_simple+0x930/0x930 [ 79.674419][ T8479] evict+0x2ed/0x6b0 [ 79.678303][ T8479] iput.part.0+0x57e/0x810 [ 79.682721][ T8479] ? find_inode_nowait+0x190/0x190 [ 79.687846][ T8479] iput+0x58/0x70 [ 79.691473][ T8479] dentry_unlink_inode+0x2b1/0x3d0 [ 79.696582][ T8479] __dentry_kill+0x3c0/0x640 [ 79.701155][ T8479] ? dput+0x35/0xbc0 [ 79.705033][ T8479] ? dput+0x35/0xbc0 [ 79.708909][ T8479] dput+0x725/0xbc0 [ 79.712700][ T8479] shrink_dcache_for_umount+0x11f/0x330 [ 79.718229][ T8479] ? lockdep_hardirqs_on+0x79/0x100 [ 79.723412][ T8479] generic_shutdown_super+0x68/0x370 [ 79.728681][ T8479] kill_anon_super+0x36/0x60 [ 79.733254][ T8479] deactivate_locked_super+0x94/0x160 [ 79.738610][ T8479] deactivate_super+0xad/0xd0 [ 79.743285][ T8479] cleanup_mnt+0x3a3/0x530 [ 79.747704][ T8479] task_work_run+0xdd/0x190 [ 79.752200][ T8479] exit_to_user_mode_prepare+0x249/0x250 [ 79.757826][ T8479] syscall_exit_to_user_mode+0x19/0x50 [ 79.763272][ T8479] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 79.769157][ T8479] RIP: 0033:0x440219 [ 79.773041][ T8479] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 79.792643][ T8479] RSP: 002b:00007ffe006d9e98 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 79.801051][ T8479] RAX: ffffffffffffffea RBX: 0030656c69662f2e RCX: 0000000000440219 [ 79.809045][ T8479] RDX: 00000000200001c0 RSI: 0000000020000300 RDI: 0000000000000000 [ 79.817002][ T8479] RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 [ 79.824957][ T8479] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a20 [ 79.832944][ T8479] R13: 0000000000401ab0 R14: 0000000000000000 R15: 0000000000000000 [ 79.841350][ T8479] Kernel Offset: disabled [ 79.845667][ T8479] Rebooting in 86400 seconds..