Warning: Permanently added '10.128.10.30' (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 syzkaller login: [ 29.566880] ================================================================== [ 29.574344] BUG: KASAN: use-after-free in ex_handler_refcount+0x164/0x1a0 [ 29.581247] Write of size 4 at addr ffff8880a305e698 by task systemd-udevd/8191 [ 29.588663] [ 29.590272] CPU: 1 PID: 8191 Comm: systemd-udevd Not tainted 4.14.281-syzkaller #0 [ 29.597949] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.607281] Call Trace: [ 29.609847] dump_stack+0x1b2/0x281 [ 29.613451] print_address_description.cold+0x54/0x1d3 [ 29.618701] kasan_report_error.cold+0x8a/0x191 [ 29.623347] ? ex_handler_refcount+0x164/0x1a0 [ 29.627907] __asan_report_store4_noabort+0x68/0x70 [ 29.632899] ? ex_handler_refcount+0x164/0x1a0 [ 29.637456] ex_handler_refcount+0x164/0x1a0 [ 29.641842] ? ex_handler_clear_fs+0xb0/0xb0 [ 29.646223] fixup_exception+0x8a/0xd0 [ 29.650084] do_trap+0x61/0x250 [ 29.653338] ? do_error_trap+0x1d0/0x2d0 [ 29.657372] do_error_trap+0x132/0x2d0 [ 29.661233] ? math_error+0x2d0/0x2d0 [ 29.665007] ? flags_string.cold+0x1b2c/0x6beb [ 29.669562] ? __mutex_lock+0x360/0x1310 [ 29.673600] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.678416] invalid_op+0x1b/0x40 [ 29.681843] RIP: 0010:flags_string.cold+0x1b2c/0x6beb [ 29.687000] RSP: 0018:ffff8880952c7cd0 EFLAGS: 00010296 [ 29.692334] RAX: 0000000000000000 RBX: ffff8880a305e698 RCX: ffff8880a305e698 [ 29.699577] RDX: 0000000000000004 RSI: 0000000000000003 RDI: 0000000000000001 [ 29.706823] RBP: ffffffff89513c80 R08: 0000000000000000 R09: 0000000000000002 [ 29.714065] R10: 0000000000000000 R11: ffff8880afc320c0 R12: 0000000000000000 [ 29.721305] R13: ffff88808a819204 R14: ffffed101150328e R15: dffffc0000000000 [ 29.728562] nbd_release+0xf3/0x150 [ 29.732164] ? nbd_queue_rq+0xc50/0xc50 [ 29.736111] __blkdev_put+0x5aa/0x800 [ 29.739886] ? revalidate_disk+0x1f0/0x1f0 [ 29.744091] ? locks_remove_file+0x2cd/0x420 [ 29.748471] ? blkdev_put+0x75/0x4c0 [ 29.752160] ? blkdev_put+0x4c0/0x4c0 [ 29.755934] blkdev_close+0x86/0xb0 [ 29.759533] __fput+0x25f/0x7a0 [ 29.762790] task_work_run+0x11f/0x190 [ 29.766652] exit_to_usermode_loop+0x1ad/0x200 [ 29.771205] do_syscall_64+0x4a3/0x640 [ 29.775069] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.780235] RIP: 0033:0x7fe128c66270 [ 29.783917] RSP: 002b:00007fffd47b2348 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 29.791595] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fe128c66270 [ 29.798839] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 29.806082] RBP: 00007fe129b20710 R08: 0000000000000045 R09: 0000000000000018 [ 29.813323] R10: 000055f9f5986f68 R11: 0000000000000246 R12: 0000000000000000 [ 29.820564] R13: 000055f9f5986dd0 R14: 0000000000000003 R15: 000000000000000e [ 29.827814] [ 29.829414] Allocated by task 8133: [ 29.833014] kasan_kmalloc+0xeb/0x160 [ 29.836801] kmem_cache_alloc_trace+0x131/0x3d0 [ 29.841445] nbd_dev_add+0x7c/0x800 [ 29.845046] nbd_genl_connect+0x3a4/0x1400 [ 29.849252] genl_family_rcv_msg+0x572/0xb20 [ 29.853629] genl_rcv_msg+0xaf/0x140 [ 29.857313] netlink_rcv_skb+0x125/0x390 [ 29.861347] genl_rcv+0x24/0x40 [ 29.864608] netlink_unicast+0x437/0x610 [ 29.868645] netlink_sendmsg+0x648/0xbc0 [ 29.872678] sock_sendmsg+0xb5/0x100 [ 29.876364] ___sys_sendmsg+0x6c8/0x800 [ 29.880311] __sys_sendmsg+0xa3/0x120 [ 29.884082] SyS_sendmsg+0x27/0x40 [ 29.887596] do_syscall_64+0x1d5/0x640 [ 29.891455] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.896611] [ 29.898209] Freed by task 8167: [ 29.901460] kasan_slab_free+0xc3/0x1a0 [ 29.905408] kfree+0xc9/0x250 [ 29.908485] nbd_put.part.0+0x100/0x140 [ 29.912430] nbd_genl_connect+0xfa9/0x1400 [ 29.916638] genl_family_rcv_msg+0x572/0xb20 [ 29.921021] genl_rcv_msg+0xaf/0x140 [ 29.924706] netlink_rcv_skb+0x125/0x390 [ 29.928744] genl_rcv+0x24/0x40 [ 29.931996] netlink_unicast+0x437/0x610 [ 29.936030] netlink_sendmsg+0x648/0xbc0 [ 29.940061] sock_sendmsg+0xb5/0x100 [ 29.943747] ___sys_sendmsg+0x6c8/0x800 [ 29.947698] __sys_sendmsg+0xa3/0x120 [ 29.951471] SyS_sendmsg+0x27/0x40 [ 29.954987] do_syscall_64+0x1d5/0x640 [ 29.958848] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.964006] [ 29.965609] The buggy address belongs to the object at ffff8880a305e5c0 [ 29.965609] which belongs to the cache kmalloc-512 of size 512 [ 29.978232] The buggy address is located 216 bytes inside of [ 29.978232] 512-byte region [ffff8880a305e5c0, ffff8880a305e7c0) [ 29.990075] The buggy address belongs to the page: [ 29.994974] page:ffffea00028c1780 count:1 mapcount:0 mapping:ffff8880a305e0c0 index:0x0 [ 30.003091] flags: 0xfff00000000100(slab) [ 30.007213] raw: 00fff00000000100 ffff8880a305e0c0 0000000000000000 0000000100000006 [ 30.015062] raw: ffffea00028651e0 ffff88813fe64748 ffff88813fe74940 0000000000000000 [ 30.022914] page dumped because: kasan: bad access detected [ 30.028593] [ 30.030194] Memory state around the buggy address: [ 30.035095] ffff8880a305e580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 30.042425] ffff8880a305e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.049752] >ffff8880a305e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.057081] ^ [ 30.061198] ffff8880a305e700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb executing program [ 30.068527] ffff8880a305e780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 30.075855] ================================================================== [ 30.083181] Disabling lock debugging due to kernel taint [ 30.092665] Kernel panic - not syncing: panic_on_warn set ... [ 30.092665] [ 30.100023] CPU: 1 PID: 8191 Comm: systemd-udevd Tainted: G B 4.14.281-syzkaller #0 [ 30.108927] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.118262] Call Trace: [ 30.120831] dump_stack+0x1b2/0x281 [ 30.124429] panic+0x1f9/0x42d [ 30.127592] ? add_taint.cold+0x16/0x16 [ 30.131539] ? ___preempt_schedule+0x16/0x18 [ 30.135917] kasan_end_report+0x43/0x49 [ 30.139862] kasan_report_error.cold+0xa7/0x191 [ 30.144506] ? ex_handler_refcount+0x164/0x1a0 [ 30.149061] __asan_report_store4_noabort+0x68/0x70 [ 30.154048] ? ex_handler_refcount+0x164/0x1a0 [ 30.158599] ex_handler_refcount+0x164/0x1a0 [ 30.162982] ? ex_handler_clear_fs+0xb0/0xb0 [ 30.167369] fixup_exception+0x8a/0xd0 [ 30.171226] do_trap+0x61/0x250 [ 30.174479] ? do_error_trap+0x1d0/0x2d0 [ 30.178511] do_error_trap+0x132/0x2d0 [ 30.182369] ? math_error+0x2d0/0x2d0 [ 30.186143] ? flags_string.cold+0x1b2c/0x6beb [ 30.190695] ? __mutex_lock+0x360/0x1310 [ 30.194726] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.199541] invalid_op+0x1b/0x40 [ 30.202970] RIP: 0010:flags_string.cold+0x1b2c/0x6beb [ 30.208128] RSP: 0018:ffff8880952c7cd0 EFLAGS: 00010296 [ 30.213463] RAX: 0000000000000000 RBX: ffff8880a305e698 RCX: ffff8880a305e698 [ 30.220706] RDX: 0000000000000004 RSI: 0000000000000003 RDI: 0000000000000001 [ 30.227945] RBP: ffffffff89513c80 R08: 0000000000000000 R09: 0000000000000002 [ 30.235185] R10: 0000000000000000 R11: ffff8880afc320c0 R12: 0000000000000000 [ 30.242423] R13: ffff88808a819204 R14: ffffed101150328e R15: dffffc0000000000 [ 30.249673] nbd_release+0xf3/0x150 [ 30.253271] ? nbd_queue_rq+0xc50/0xc50 [ 30.257217] __blkdev_put+0x5aa/0x800 [ 30.260990] ? revalidate_disk+0x1f0/0x1f0 [ 30.265195] ? locks_remove_file+0x2cd/0x420 [ 30.269579] ? blkdev_put+0x75/0x4c0 [ 30.273262] ? blkdev_put+0x4c0/0x4c0 [ 30.277031] blkdev_close+0x86/0xb0 [ 30.280629] __fput+0x25f/0x7a0 [ 30.283881] task_work_run+0x11f/0x190 [ 30.287743] exit_to_usermode_loop+0x1ad/0x200 [ 30.292297] do_syscall_64+0x4a3/0x640 [ 30.296160] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.301319] RIP: 0033:0x7fe128c66270 [ 30.305007] RSP: 002b:00007fffd47b2348 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 30.312694] RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fe128c66270 [ 30.319938] RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 [ 30.327179] RBP: 00007fe129b20710 R08: 0000000000000045 R09: 0000000000000018 [ 30.334420] R10: 000055f9f5986f68 R11: 0000000000000246 R12: 0000000000000000 [ 30.341667] R13: 000055f9f5986dd0 R14: 0000000000000003 R15: 000000000000000e [ 30.349072] Kernel Offset: disabled [ 30.352676] Rebooting in 86400 seconds..