[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.66' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 40.852840] netlink: 36 bytes leftover after parsing attributes in process `syz-executor277'. [ 40.864139] netlink: 4 bytes leftover after parsing attributes in process `syz-executor277'. executing program [ 40.912306] netlink: 36 bytes leftover after parsing attributes in process `syz-executor277'. [ 40.921861] netlink: 4 bytes leftover after parsing attributes in process `syz-executor277'. executing program [ 40.971284] netlink: 36 bytes leftover after parsing attributes in process `syz-executor277'. [ 40.980236] netlink: 4 bytes leftover after parsing attributes in process `syz-executor277'. executing program [ 41.011925] netlink: 36 bytes leftover after parsing attributes in process `syz-executor277'. [ 41.021963] netlink: 4 bytes leftover after parsing attributes in process `syz-executor277'. executing program executing program [ 41.071256] netlink: 36 bytes leftover after parsing attributes in process `syz-executor277'. [ 41.080356] netlink: 4 bytes leftover after parsing attributes in process `syz-executor277'. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 42.142346] ================================================================== [ 42.149878] BUG: KASAN: use-after-free in ex_handler_refcount+0x18f/0x1c0 [ 42.156894] Write of size 4 at addr ffff8880a303fad8 by task systemd-udevd/8280 [ 42.164322] [ 42.165945] CPU: 0 PID: 8280 Comm: systemd-udevd Not tainted 4.19.211-syzkaller #0 [ 42.173644] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.182981] Call Trace: [ 42.185564] dump_stack+0x1fc/0x2ef [ 42.189177] print_address_description.cold+0x54/0x219 [ 42.194438] kasan_report_error.cold+0x8a/0x1b9 [ 42.199089] ? ex_handler_refcount+0x18f/0x1c0 [ 42.203655] __asan_report_store4_noabort+0x88/0x90 [ 42.208662] ? notify_die+0x21/0x170 [ 42.212372] ? ex_handler_refcount+0x18f/0x1c0 [ 42.216940] ex_handler_refcount+0x18f/0x1c0 [ 42.221337] ? ex_handler_clear_fs+0xb0/0xb0 [ 42.225726] fixup_exception+0x8a/0xd0 [ 42.229595] do_trap+0x61/0x250 [ 42.232865] ? do_error_trap+0x212/0x310 [ 42.236915] do_error_trap+0x15d/0x310 [ 42.240783] ? math_error+0x310/0x310 [ 42.244571] ? __noinstr_text_end+0x243b/0x7813 [ 42.249237] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.254062] invalid_op+0x14/0x20 [ 42.257525] RIP: 0010:__noinstr_text_end+0x243b/0x7813 [ 42.262798] Code: 0f 0b 48 8d 4b 50 0f 0b 48 8d 4b 08 0f 0b 48 8d 4d 08 0f 0b 48 8d 8d 08 02 00 00 0f 0b 48 8d 0b 0f 0b 48 8d 0b 0f 0b 48 8d 0b <0f> 0b 48 8d 4d 00 0f 0b 49 8d 0c 24 0f 0b 48 8d 8b c0 00 00 00 0f [ 42.281705] RSP: 0018:ffff8880afee7cd8 EFLAGS: 00010296 [ 42.287063] RAX: 0000000000000000 RBX: ffff8880a303fad8 RCX: ffff8880a303fad8 [ 42.294325] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000001 [ 42.301592] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff14b7985 [ 42.308883] R10: ffffffff8a5bcc2b R11: 0000000000000000 R12: ffffffff8a5bcc20 [ 42.316146] R13: 0000000000000000 R14: 1ffff11011610335 R15: dffffc0000000000 [ 42.323426] ? refcount_dec_and_mutex_lock+0x4a/0x80 [ 42.328522] nbd_release+0x108/0x170 [ 42.332228] ? nbd_queue_rq+0xe60/0xe60 [ 42.336200] __blkdev_put+0x636/0x870 [ 42.339986] ? fsync_bdev+0xc0/0xc0 [ 42.343590] ? locks_remove_file+0x2cd/0x450 [ 42.347984] ? blkdev_put+0x85/0x520 [ 42.351679] ? blkdev_put+0x520/0x520 [ 42.355460] blkdev_close+0x86/0xb0 [ 42.359086] __fput+0x2ce/0x890 [ 42.362402] task_work_run+0x148/0x1c0 [ 42.366298] exit_to_usermode_loop+0x251/0x2a0 [ 42.370865] do_syscall_64+0x538/0x620 [ 42.374823] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.379995] RIP: 0033:0x7fa987df4270 [ 42.383693] Code: 73 01 c3 48 8b 0d 38 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 59 c1 20 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 [ 42.402598] RSP: 002b:00007ffdbb2c5df8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 42.410319] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fa987df4270 [ 42.417569] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 42.424817] RBP: 00007fa988cae710 R08: 0000000000000045 R09: 0000000000000018 [ 42.432079] R10: 000056178b36fde8 R11: 0000000000000246 R12: 0000000000000000 [ 42.439345] R13: 000056178b36b6e0 R14: 0000000000000003 R15: 000000000000000e [ 42.446689] [ 42.448299] Allocated by task 8256: [ 42.451919] kmem_cache_alloc_trace+0x12f/0x380 [ 42.456572] nbd_dev_add+0x44/0x890 [ 42.460179] nbd_genl_connect+0x4cc/0x1630 [ 42.464394] genl_family_rcv_msg+0x642/0xc40 [ 42.468796] genl_rcv_msg+0xbf/0x160 [ 42.472494] netlink_rcv_skb+0x160/0x440 [ 42.476574] genl_rcv+0x24/0x40 [ 42.479848] netlink_unicast+0x4d5/0x690 [ 42.483893] netlink_sendmsg+0x6c3/0xc50 [ 42.487936] sock_sendmsg+0xc3/0x120 [ 42.491771] ___sys_sendmsg+0x7bb/0x8e0 [ 42.495725] __x64_sys_sendmsg+0x132/0x220 [ 42.499947] do_syscall_64+0xf9/0x620 [ 42.503737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.508907] [ 42.510521] Freed by task 8271: [ 42.513782] kfree+0xcc/0x210 [ 42.516867] nbd_put.part.0+0xfe/0x140 [ 42.520745] nbd_genl_connect+0x120e/0x1630 [ 42.525053] genl_family_rcv_msg+0x642/0xc40 [ 42.529438] genl_rcv_msg+0xbf/0x160 [ 42.533130] netlink_rcv_skb+0x160/0x440 [ 42.537170] genl_rcv+0x24/0x40 [ 42.540429] netlink_unicast+0x4d5/0x690 [ 42.544467] netlink_sendmsg+0x6c3/0xc50 [ 42.548511] sock_sendmsg+0xc3/0x120 [ 42.552212] ___sys_sendmsg+0x7bb/0x8e0 [ 42.556217] __x64_sys_sendmsg+0x132/0x220 [ 42.560442] do_syscall_64+0xf9/0x620 [ 42.564231] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.569394] [ 42.571011] The buggy address belongs to the object at ffff8880a303fa00 [ 42.571011] which belongs to the cache kmalloc-512 of size 512 [ 42.583658] The buggy address is located 216 bytes inside of [ 42.583658] 512-byte region [ffff8880a303fa00, ffff8880a303fc00) [ 42.595515] The buggy address belongs to the page: [ 42.600437] page:ffffea00028c0fc0 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 [ 42.608564] flags: 0xfff00000000100(slab) [ 42.612697] raw: 00fff00000000100 ffffea0002911008 ffffea00028d2288 ffff88813bff0940 [ 42.620560] raw: 0000000000000000 ffff8880a303f000 0000000100000006 0000000000000000 [ 42.628417] page dumped because: kasan: bad access detected [ 42.634126] [ 42.635730] Memory state around the buggy address: [ 42.640648] ffff8880a303f980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.647991] ffff8880a303fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.655329] >ffff8880a303fa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.662665] ^ [ 42.668884] ffff8880a303fb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.676222] ffff8880a303fb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.683556] ================================================================== [ 42.690887] Disabling lock debugging due to kernel taint [ 42.702556] Kernel panic - not syncing: panic_on_warn set ... [ 42.702556] [ 42.709945] CPU: 1 PID: 8280 Comm: systemd-udevd Tainted: G B 4.19.211-syzkaller #0 [ 42.719033] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.728378] Call Trace: [ 42.730949] dump_stack+0x1fc/0x2ef [ 42.734557] panic+0x26a/0x50e [ 42.737727] ? __warn_printk+0xf3/0xf3 [ 42.741592] ? preempt_schedule_common+0x45/0xc0 [ 42.746327] ? ___preempt_schedule+0x16/0x18 [ 42.750721] ? trace_hardirqs_on+0x55/0x210 [ 42.755024] kasan_end_report+0x43/0x49 [ 42.758989] kasan_report_error.cold+0xa7/0x1b9 [ 42.763635] ? ex_handler_refcount+0x18f/0x1c0 [ 42.768196] __asan_report_store4_noabort+0x88/0x90 [ 42.773205] ? notify_die+0x21/0x170 [ 42.776923] ? ex_handler_refcount+0x18f/0x1c0 [ 42.781491] ex_handler_refcount+0x18f/0x1c0 [ 42.785907] ? ex_handler_clear_fs+0xb0/0xb0 [ 42.790300] fixup_exception+0x8a/0xd0 [ 42.794182] do_trap+0x61/0x250 [ 42.797450] ? do_error_trap+0x212/0x310 [ 42.801494] do_error_trap+0x15d/0x310 [ 42.805362] ? math_error+0x310/0x310 [ 42.809156] ? __noinstr_text_end+0x243b/0x7813 [ 42.813937] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.818777] invalid_op+0x14/0x20 [ 42.822216] RIP: 0010:__noinstr_text_end+0x243b/0x7813 [ 42.827484] Code: 0f 0b 48 8d 4b 50 0f 0b 48 8d 4b 08 0f 0b 48 8d 4d 08 0f 0b 48 8d 8d 08 02 00 00 0f 0b 48 8d 0b 0f 0b 48 8d 0b 0f 0b 48 8d 0b <0f> 0b 48 8d 4d 00 0f 0b 49 8d 0c 24 0f 0b 48 8d 8b c0 00 00 00 0f [ 42.846360] RSP: 0018:ffff8880afee7cd8 EFLAGS: 00010296 [ 42.851699] RAX: 0000000000000000 RBX: ffff8880a303fad8 RCX: ffff8880a303fad8 [ 42.858946] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000001 [ 42.866190] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff14b7985 [ 42.873438] R10: ffffffff8a5bcc2b R11: 0000000000000000 R12: ffffffff8a5bcc20 [ 42.880683] R13: 0000000000000000 R14: 1ffff11011610335 R15: dffffc0000000000 [ 42.887953] ? refcount_dec_and_mutex_lock+0x4a/0x80 [ 42.893036] nbd_release+0x108/0x170 [ 42.896731] ? nbd_queue_rq+0xe60/0xe60 [ 42.900681] __blkdev_put+0x636/0x870 [ 42.904462] ? fsync_bdev+0xc0/0xc0 [ 42.908069] ? locks_remove_file+0x2cd/0x450 [ 42.912476] ? blkdev_put+0x85/0x520 [ 42.917231] ? blkdev_put+0x520/0x520 [ 42.921018] blkdev_close+0x86/0xb0 [ 42.924627] __fput+0x2ce/0x890 [ 42.927895] task_work_run+0x148/0x1c0 [ 42.931764] exit_to_usermode_loop+0x251/0x2a0 [ 42.936336] do_syscall_64+0x538/0x620 [ 42.940215] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.945392] RIP: 0033:0x7fa987df4270 [ 42.949090] Code: 73 01 c3 48 8b 0d 38 7d 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 59 c1 20 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ee fb ff ff 48 89 04 24 [ 42.967968] RSP: 002b:00007ffdbb2c5df8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 42.975650] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fa987df4270 [ 42.982981] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 42.990226] RBP: 00007fa988cae710 R08: 0000000000000045 R09: 0000000000000018 [ 42.997472] R10: 000056178b36fde8 R11: 0000000000000246 R12: 0000000000000000 [ 43.004820] R13: 000056178b36b6e0 R14: 0000000000000003 R15: 000000000000000e [ 43.012339] Kernel Offset: disabled [ 43.015955] Rebooting in 86400 seconds..