[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.32' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 61.706073][ T8456] ================================================================== [ 61.714800][ T8456] BUG: KASAN: null-ptr-deref in bdi_put+0x22/0xa0 [ 61.721297][ T8456] Write of size 4 at addr 0000000000000040 by task syz-executor526/8456 [ 61.729598][ T8456] [ 61.731907][ T8456] CPU: 0 PID: 8456 Comm: syz-executor526 Not tainted 5.11.0-rc2-syzkaller #0 [ 61.741704][ T8456] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.751740][ T8456] Call Trace: [ 61.755007][ T8456] dump_stack+0x107/0x163 [ 61.760322][ T8456] ? bdi_put+0x22/0xa0 [ 61.764372][ T8456] ? bdi_put+0x22/0xa0 [ 61.768679][ T8456] kasan_report.cold+0x5f/0xd5 [ 61.773607][ T8456] ? bdi_put+0x22/0xa0 [ 61.777755][ T8456] check_memory_region+0x13d/0x180 [ 61.782877][ T8456] bdi_put+0x22/0xa0 [ 61.786767][ T8456] bdev_evict_inode+0x262/0x460 [ 61.791622][ T8456] ? __blkdev_direct_IO_simple+0x930/0x930 [ 61.797411][ T8456] evict+0x2ed/0x6b0 [ 61.801308][ T8456] iput.part.0+0x57e/0x810 [ 61.805704][ T8456] ? find_inode_nowait+0x190/0x190 [ 61.810812][ T8456] iput+0x58/0x70 [ 61.814438][ T8456] dentry_unlink_inode+0x2b1/0x3d0 [ 61.819530][ T8456] __dentry_kill+0x3c0/0x640 [ 61.824099][ T8456] ? dput+0x35/0xbc0 [ 61.827974][ T8456] ? dput+0x35/0xbc0 [ 61.831952][ T8456] dput+0x725/0xbc0 [ 61.835745][ T8456] shrink_dcache_for_umount+0x11f/0x330 [ 61.841288][ T8456] generic_shutdown_super+0x68/0x370 [ 61.846566][ T8456] kill_anon_super+0x36/0x60 [ 61.851167][ T8456] deactivate_locked_super+0x94/0x160 [ 61.856524][ T8456] deactivate_super+0xad/0xd0 [ 61.861185][ T8456] put_fs_context+0xaa/0x650 [ 61.865762][ T8456] ? __sanitizer_cov_trace_const_cmp2+0x22/0x80 [ 61.872096][ T8456] fscontext_release+0x4c/0x60 [ 61.876954][ T8456] __fput+0x283/0x920 [ 61.880922][ T8456] ? fs_validate_description+0x1d0/0x1d0 [ 61.886557][ T8456] task_work_run+0xdd/0x190 [ 61.891089][ T8456] do_exit+0xc5c/0x2ae0 [ 61.895252][ T8456] ? kfree+0x2d3/0x360 [ 61.899313][ T8456] ? mm_update_next_owner+0x7a0/0x7a0 [ 61.904672][ T8456] ? __do_sys_fsconfig+0x1c2/0xbd0 [ 61.909777][ T8456] ? fscontext_read+0x310/0x310 [ 61.914626][ T8456] do_group_exit+0x125/0x310 [ 61.919299][ T8456] __x64_sys_exit_group+0x3a/0x50 [ 61.924312][ T8456] do_syscall_64+0x2d/0x70 [ 61.928766][ T8456] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.934662][ T8456] RIP: 0033:0x43ee78 [ 61.938547][ T8456] Code: Unable to access opcode bytes at RIP 0x43ee4e. [ 61.945377][ T8456] RSP: 002b:00007ffe6ec80388 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 61.953792][ T8456] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ee78 [ 61.961744][ T8456] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 61.969956][ T8456] RBP: 00000000004be688 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 61.977927][ T8456] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 61.985883][ T8456] R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000 [ 61.993846][ T8456] ================================================================== [ 62.001880][ T8456] Disabling lock debugging due to kernel taint [ 62.009423][ T8456] Kernel panic - not syncing: panic_on_warn set ... [ 62.016023][ T8456] CPU: 1 PID: 8456 Comm: syz-executor526 Tainted: G B 5.11.0-rc2-syzkaller #0 [ 62.027692][ T8456] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.037820][ T8456] Call Trace: [ 62.041100][ T8456] dump_stack+0x107/0x163 [ 62.045414][ T8456] ? bdi_alloc+0x90/0x140 [ 62.049894][ T8456] panic+0x306/0x73d [ 62.053767][ T8456] ? __warn_printk+0xf3/0xf3 [ 62.058333][ T8456] ? preempt_schedule_common+0x59/0xc0 [ 62.063768][ T8456] ? bdi_put+0x22/0xa0 [ 62.067813][ T8456] ? preempt_schedule_thunk+0x16/0x18 [ 62.073184][ T8456] ? trace_hardirqs_on+0x38/0x1c0 [ 62.087719][ T8456] ? trace_hardirqs_on+0x51/0x1c0 [ 62.093058][ T8456] ? bdi_put+0x22/0xa0 [ 62.097555][ T8456] ? bdi_put+0x22/0xa0 [ 62.101623][ T8456] end_report+0x58/0x5e [ 62.105766][ T8456] kasan_report.cold+0x67/0xd5 [ 62.110603][ T8456] ? bdi_put+0x22/0xa0 [ 62.114657][ T8456] check_memory_region+0x13d/0x180 [ 62.119756][ T8456] bdi_put+0x22/0xa0 [ 62.123632][ T8456] bdev_evict_inode+0x262/0x460 [ 62.128465][ T8456] ? __blkdev_direct_IO_simple+0x930/0x930 [ 62.134434][ T8456] evict+0x2ed/0x6b0 [ 62.138325][ T8456] iput.part.0+0x57e/0x810 [ 62.142728][ T8456] ? find_inode_nowait+0x190/0x190 [ 62.148002][ T8456] iput+0x58/0x70 [ 62.151793][ T8456] dentry_unlink_inode+0x2b1/0x3d0 [ 62.156905][ T8456] __dentry_kill+0x3c0/0x640 [ 62.161476][ T8456] ? dput+0x35/0xbc0 [ 62.165369][ T8456] ? dput+0x35/0xbc0 [ 62.169330][ T8456] dput+0x725/0xbc0 [ 62.173133][ T8456] shrink_dcache_for_umount+0x11f/0x330 [ 62.178668][ T8456] generic_shutdown_super+0x68/0x370 [ 62.183953][ T8456] kill_anon_super+0x36/0x60 [ 62.188522][ T8456] deactivate_locked_super+0x94/0x160 [ 62.193962][ T8456] deactivate_super+0xad/0xd0 [ 62.198624][ T8456] put_fs_context+0xaa/0x650 [ 62.203302][ T8456] ? __sanitizer_cov_trace_const_cmp2+0x22/0x80 [ 62.209533][ T8456] fscontext_release+0x4c/0x60 [ 62.214303][ T8456] __fput+0x283/0x920 [ 62.218272][ T8456] ? fs_validate_description+0x1d0/0x1d0 [ 62.223998][ T8456] task_work_run+0xdd/0x190 [ 62.228582][ T8456] do_exit+0xc5c/0x2ae0 [ 62.232721][ T8456] ? kfree+0x2d3/0x360 [ 62.236791][ T8456] ? mm_update_next_owner+0x7a0/0x7a0 [ 62.242164][ T8456] ? __do_sys_fsconfig+0x1c2/0xbd0 [ 62.247268][ T8456] ? fscontext_read+0x310/0x310 [ 62.252324][ T8456] do_group_exit+0x125/0x310 [ 62.256940][ T8456] __x64_sys_exit_group+0x3a/0x50 [ 62.261943][ T8456] do_syscall_64+0x2d/0x70 [ 62.266349][ T8456] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.272242][ T8456] RIP: 0033:0x43ee78 [ 62.276285][ T8456] Code: Unable to access opcode bytes at RIP 0x43ee4e. [ 62.283116][ T8456] RSP: 002b:00007ffe6ec80388 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 62.291509][ T8456] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ee78 [ 62.299894][ T8456] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 62.307839][ T8456] RBP: 00000000004be688 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 62.315786][ T8456] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 62.323731][ T8456] R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000 [ 62.334641][ T8456] Kernel Offset: disabled [ 62.338950][ T8456] Rebooting in 86400 seconds..