[ 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 '10.128.10.43' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 28.090702] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program [ 28.154432] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program [ 28.203683] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program [ 28.263790] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program [ 28.313504] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program executing program [ 28.363945] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. [ 28.403416] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program [ 28.453877] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program executing program [ 28.503890] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. [ 28.543786] netlink: 4 bytes leftover after parsing attributes in process `syz-executor836'. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 30.142368] ================================================================== [ 30.150029] BUG: KASAN: use-after-free in ex_handler_refcount+0x164/0x1a0 [ 30.156942] Write of size 4 at addr ffff8880b454cd58 by task systemd-udevd/8274 [ 30.164369] [ 30.165982] CPU: 0 PID: 8274 Comm: systemd-udevd Not tainted 4.14.232-syzkaller #0 [ 30.173732] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.183069] Call Trace: [ 30.185644] dump_stack+0x1b2/0x281 [ 30.189276] print_address_description.cold+0x54/0x1d3 [ 30.194536] kasan_report_error.cold+0x8a/0x191 [ 30.199206] ? ex_handler_refcount+0x164/0x1a0 [ 30.203787] __asan_report_store4_noabort+0x68/0x70 [ 30.208808] ? ex_handler_refcount+0x164/0x1a0 [ 30.213371] ex_handler_refcount+0x164/0x1a0 [ 30.217760] ? ex_handler_clear_fs+0xb0/0xb0 [ 30.222150] fixup_exception+0x8a/0xd0 [ 30.226028] do_trap+0x61/0x250 [ 30.229287] ? do_error_trap+0x1d0/0x2d0 [ 30.233330] do_error_trap+0x132/0x2d0 [ 30.237201] ? math_error+0x2d0/0x2d0 [ 30.240991] ? flags_string.cold+0x1b15/0x6a9e [ 30.245562] ? __mutex_lock+0x360/0x1310 [ 30.249616] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.254446] invalid_op+0x1b/0x40 [ 30.257894] RIP: 0010:flags_string.cold+0x1b15/0x6a9e [ 30.263065] RSP: 0018:ffff8880afa4fcd0 EFLAGS: 00010296 [ 30.268408] RAX: 0000000000000000 RBX: ffff8880b454cd58 RCX: ffff8880b454cd58 [ 30.275830] RDX: 0000000000000004 RSI: 0000000000000003 RDI: 0000000000000001 [ 30.283114] RBP: ffffffff89512740 R08: 0000000000000000 R09: 0000000000000002 [ 30.290363] R10: 0000000000000000 R11: ffff8880af43a400 R12: 0000000000000000 [ 30.297614] R13: ffff88808a8c1044 R14: ffffed1011518256 R15: dffffc0000000000 [ 30.304896] nbd_release+0xf3/0x150 [ 30.308506] ? nbd_queue_rq+0xc50/0xc50 [ 30.312466] __blkdev_put+0x5aa/0x800 [ 30.316258] ? revalidate_disk+0x1f0/0x1f0 [ 30.320473] ? locks_remove_file+0x2cd/0x420 [ 30.324865] ? blkdev_put+0x75/0x4c0 [ 30.328576] ? blkdev_put+0x4c0/0x4c0 [ 30.332362] blkdev_close+0x86/0xb0 [ 30.335977] __fput+0x25f/0x7a0 [ 30.339256] task_work_run+0x11f/0x190 [ 30.343202] exit_to_usermode_loop+0x1ad/0x200 [ 30.347796] do_syscall_64+0x4a3/0x640 [ 30.351669] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.356840] RIP: 0033:0x7f9358347270 [ 30.360534] RSP: 002b:00007ffcf1a61908 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 30.368257] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007f9358347270 [ 30.375521] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 30.382773] RBP: 00007f9359201710 R08: 000056258ff11580 R09: 0000000000000018 [ 30.390032] R10: 000056258ff11c48 R11: 0000000000000246 R12: 0000000000000000 [ 30.397281] R13: 000056258ff0e880 R14: 0000000000000003 R15: 000000000000000e [ 30.404545] [ 30.406168] Allocated by task 8252: [ 30.409795] kasan_kmalloc+0xeb/0x160 [ 30.413592] kmem_cache_alloc_trace+0x131/0x3d0 [ 30.418250] nbd_dev_add+0x7c/0x800 [ 30.421863] nbd_genl_connect+0x3a4/0x1400 [ 30.426196] genl_family_rcv_msg+0x572/0xb20 [ 30.430672] genl_rcv_msg+0xaf/0x140 [ 30.434377] netlink_rcv_skb+0x125/0x390 [ 30.438415] genl_rcv+0x24/0x40 [ 30.441675] netlink_unicast+0x437/0x610 [ 30.445713] netlink_sendmsg+0x62e/0xb80 [ 30.449761] sock_sendmsg+0xb5/0x100 [ 30.453453] ___sys_sendmsg+0x6c8/0x800 [ 30.457405] __sys_sendmsg+0xa3/0x120 [ 30.461182] SyS_sendmsg+0x27/0x40 [ 30.464719] do_syscall_64+0x1d5/0x640 [ 30.468594] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.473764] [ 30.475375] Freed by task 8264: [ 30.478637] kasan_slab_free+0xc3/0x1a0 [ 30.482598] kfree+0xc9/0x250 [ 30.485693] nbd_put.part.0+0x100/0x140 [ 30.489661] nbd_genl_connect+0xfa9/0x1400 [ 30.493883] genl_family_rcv_msg+0x572/0xb20 [ 30.498283] genl_rcv_msg+0xaf/0x140 [ 30.501985] netlink_rcv_skb+0x125/0x390 [ 30.506063] genl_rcv+0x24/0x40 [ 30.509344] netlink_unicast+0x437/0x610 [ 30.513405] netlink_sendmsg+0x62e/0xb80 [ 30.517443] sock_sendmsg+0xb5/0x100 [ 30.521137] ___sys_sendmsg+0x6c8/0x800 [ 30.525104] __sys_sendmsg+0xa3/0x120 [ 30.528886] SyS_sendmsg+0x27/0x40 [ 30.532414] do_syscall_64+0x1d5/0x640 [ 30.536294] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.541458] [ 30.543073] The buggy address belongs to the object at ffff8880b454cc80 [ 30.543073] which belongs to the cache kmalloc-512 of size 512 [ 30.555722] The buggy address is located 216 bytes inside of [ 30.555722] 512-byte region [ffff8880b454cc80, ffff8880b454ce80) [ 30.567581] The buggy address belongs to the page: [ 30.572499] page:ffffea0002d15300 count:1 mapcount:0 mapping:ffff8880b454c000 index:0x0 [ 30.580633] flags: 0xfff00000000100(slab) [ 30.584768] raw: 00fff00000000100 ffff8880b454c000 0000000000000000 0000000100000006 [ 30.592628] raw: ffffea0002ce3220 ffffea0002d0b6a0 ffff88813fe80940 0000000000000000 [ 30.600486] page dumped because: kasan: bad access detected [ 30.606175] [ 30.607786] Memory state around the buggy address: [ 30.612701] ffff8880b454cc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.620044] ffff8880b454cc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.627408] >ffff8880b454cd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.634746] ^ [ 30.640959] ffff8880b454cd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.648296] ffff8880b454ce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.655632] ================================================================== [ 30.662969] Disabling lock debugging due to kernel taint [ 30.668701] Kernel panic - not syncing: panic_on_warn set ... [ 30.668701] [ 30.676071] CPU: 0 PID: 8274 Comm: systemd-udevd Tainted: G B 4.14.232-syzkaller #0 [ 30.684989] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.694343] Call Trace: [ 30.696932] dump_stack+0x1b2/0x281 [ 30.700559] panic+0x1f9/0x42d [ 30.703742] ? add_taint.cold+0x16/0x16 [ 30.707692] ? ___preempt_schedule+0x16/0x18 [ 30.712079] kasan_end_report+0x43/0x49 [ 30.716029] kasan_report_error.cold+0xa7/0x191 [ 30.720676] ? ex_handler_refcount+0x164/0x1a0 [ 30.725237] __asan_report_store4_noabort+0x68/0x70 [ 30.730231] ? ex_handler_refcount+0x164/0x1a0 [ 30.735109] ex_handler_refcount+0x164/0x1a0 [ 30.740137] ? ex_handler_clear_fs+0xb0/0xb0 [ 30.744534] fixup_exception+0x8a/0xd0 [ 30.748406] do_trap+0x61/0x250 [ 30.751668] ? do_error_trap+0x1d0/0x2d0 [ 30.755706] do_error_trap+0x132/0x2d0 [ 30.759572] ? math_error+0x2d0/0x2d0 [ 30.763351] ? flags_string.cold+0x1b15/0x6a9e [ 30.767909] ? __mutex_lock+0x360/0x1310 [ 30.771950] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.776771] invalid_op+0x1b/0x40 [ 30.780203] RIP: 0010:flags_string.cold+0x1b15/0x6a9e [ 30.785368] RSP: 0018:ffff8880afa4fcd0 EFLAGS: 00010296 [ 30.790710] RAX: 0000000000000000 RBX: ffff8880b454cd58 RCX: ffff8880b454cd58 [ 30.797956] RDX: 0000000000000004 RSI: 0000000000000003 RDI: 0000000000000001 [ 30.805204] RBP: ffffffff89512740 R08: 0000000000000000 R09: 0000000000000002 [ 30.812470] R10: 0000000000000000 R11: ffff8880af43a400 R12: 0000000000000000 [ 30.819718] R13: ffff88808a8c1044 R14: ffffed1011518256 R15: dffffc0000000000 [ 30.826977] nbd_release+0xf3/0x150 [ 30.830611] ? nbd_queue_rq+0xc50/0xc50 [ 30.834565] __blkdev_put+0x5aa/0x800 [ 30.838370] ? revalidate_disk+0x1f0/0x1f0 [ 30.842584] ? locks_remove_file+0x2cd/0x420 [ 30.846969] ? blkdev_put+0x75/0x4c0 [ 30.850669] ? blkdev_put+0x4c0/0x4c0 [ 30.854455] blkdev_close+0x86/0xb0 [ 30.858061] __fput+0x25f/0x7a0 [ 30.861332] task_work_run+0x11f/0x190 [ 30.865215] exit_to_usermode_loop+0x1ad/0x200 [ 30.869784] do_syscall_64+0x4a3/0x640 [ 30.873658] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.878832] RIP: 0033:0x7f9358347270 [ 30.882525] RSP: 002b:00007ffcf1a61908 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 30.890224] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007f9358347270 [ 30.897633] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 30.904884] RBP: 00007f9359201710 R08: 000056258ff11580 R09: 0000000000000018 [ 30.912147] R10: 000056258ff11c48 R11: 0000000000000246 R12: 0000000000000000 [ 30.919394] R13: 000056258ff0e880 R14: 0000000000000003 R15: 000000000000000e [ 30.927357] Kernel Offset: disabled [ 30.930967] Rebooting in 86400 seconds..