Warning: Permanently added '10.128.1.6' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.740603] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.749742] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.758952] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.767820] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.776730] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.785660] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.794860] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.803912] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.812617] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. [ 29.821505] netlink: 4 bytes leftover after parsing attributes in process `syz-executor458'. 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 [ 30.674504] ================================================================== [ 30.682134] BUG: KASAN: use-after-free in refcount_dec_not_one+0x9a/0xc0 [ 30.689133] Read of size 4 at addr ffff8880aab465d8 by task syz-executor458/8095 [ 30.696652] [ 30.698266] CPU: 1 PID: 8095 Comm: syz-executor458 Not tainted 4.14.234-syzkaller #0 [ 30.706123] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.715481] Call Trace: [ 30.718053] dump_stack+0x1b2/0x281 [ 30.721685] print_address_description.cold+0x54/0x1d3 [ 30.726947] kasan_report_error.cold+0x8a/0x191 [ 30.731693] ? refcount_dec_not_one+0x9a/0xc0 [ 30.736472] __asan_report_load4_noabort+0x68/0x70 [ 30.741435] ? refcount_dec_not_one+0x9a/0xc0 [ 30.746004] refcount_dec_not_one+0x9a/0xc0 [ 30.750504] refcount_dec_and_mutex_lock+0x1a/0x60 [ 30.755414] nbd_genl_connect+0xf94/0x1400 [ 30.759629] ? nbd_xmit_timeout+0x500/0x500 [ 30.763935] ? validate_nla+0x192/0x5e0 [ 30.767904] genl_family_rcv_msg+0x572/0xb20 [ 30.772288] ? genl_rcv+0x40/0x40 [ 30.775745] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 30.781175] ? trace_hardirqs_on+0x10/0x10 [ 30.785386] ? sock_sendmsg+0xb5/0x100 [ 30.789251] genl_rcv_msg+0xaf/0x140 [ 30.792944] netlink_rcv_skb+0x125/0x390 [ 30.796999] ? genl_family_rcv_msg+0xb20/0xb20 [ 30.801557] ? netlink_ack+0x9a0/0x9a0 [ 30.805565] ? lock_acquire+0x170/0x3f0 [ 30.809775] genl_rcv+0x24/0x40 [ 30.813324] netlink_unicast+0x437/0x610 [ 30.817505] ? netlink_sendskb+0xd0/0xd0 [ 30.821558] ? __check_object_size+0x179/0x230 [ 30.826127] netlink_sendmsg+0x62e/0xb80 [ 30.830190] ? nlmsg_notify+0x170/0x170 [ 30.834142] ? kernel_recvmsg+0x210/0x210 [ 30.838359] ? security_socket_sendmsg+0x83/0xb0 [ 30.843097] ? nlmsg_notify+0x170/0x170 [ 30.847064] sock_sendmsg+0xb5/0x100 [ 30.850788] ___sys_sendmsg+0x6c8/0x800 [ 30.855178] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 30.859915] ? netlink_dump+0xad0/0xad0 [ 30.864047] ? nlmsg_notify+0x170/0x170 [ 30.868020] ? security_socket_recvmsg+0x8b/0xc0 [ 30.872771] ? SyS_recvfrom+0x27f/0x340 [ 30.876723] ? SyS_send+0x40/0x40 [ 30.880158] ? vm_insert_page+0x7c0/0x7c0 [ 30.884304] ? __fdget+0x167/0x1f0 [ 30.887838] ? sockfd_lookup_light+0xb2/0x160 [ 30.892313] __sys_sendmsg+0xa3/0x120 [ 30.896096] ? SyS_shutdown+0x160/0x160 [ 30.900081] ? up_read+0x17/0x30 [ 30.903439] ? __do_page_fault+0x159/0xad0 [ 30.907741] SyS_sendmsg+0x27/0x40 [ 30.911260] ? __sys_sendmsg+0x120/0x120 [ 30.915313] do_syscall_64+0x1d5/0x640 [ 30.919316] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 30.924750] RIP: 0033:0x4408d9 [ 30.927919] RSP: 002b:00007fff98e49a18 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 30.935721] RAX: ffffffffffffffda RBX: 00000000000077b3 RCX: 00000000004408d9 [ 30.942988] RDX: 0000000000000040 RSI: 0000000020000a00 RDI: 0000000000000004 [ 30.950253] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff98e49bb8 [ 30.957592] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff98e49a2c [ 30.965397] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 30.972834] [ 30.974440] Allocated by task 8092: [ 30.978149] kasan_kmalloc+0xeb/0x160 [ 30.981932] kmem_cache_alloc_trace+0x131/0x3d0 [ 30.986814] nbd_dev_add+0x7c/0x800 [ 30.990420] nbd_genl_connect+0x3a4/0x1400 [ 30.994664] genl_family_rcv_msg+0x572/0xb20 [ 30.999062] genl_rcv_msg+0xaf/0x140 [ 31.002774] netlink_rcv_skb+0x125/0x390 [ 31.006811] genl_rcv+0x24/0x40 [ 31.010068] netlink_unicast+0x437/0x610 [ 31.014205] netlink_sendmsg+0x62e/0xb80 [ 31.018327] sock_sendmsg+0xb5/0x100 [ 31.022026] ___sys_sendmsg+0x6c8/0x800 [ 31.026065] __sys_sendmsg+0xa3/0x120 [ 31.030105] SyS_sendmsg+0x27/0x40 [ 31.033623] do_syscall_64+0x1d5/0x640 [ 31.037486] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 31.042749] [ 31.044351] Freed by task 8095: [ 31.047607] kasan_slab_free+0xc3/0x1a0 [ 31.051583] kfree+0xc9/0x250 [ 31.054764] nbd_put.part.0+0x100/0x140 [ 31.059243] nbd_config_put+0x62a/0x810 [ 31.063198] nbd_genl_connect+0xf6c/0x1400 [ 31.067408] genl_family_rcv_msg+0x572/0xb20 [ 31.071797] genl_rcv_msg+0xaf/0x140 [ 31.075487] netlink_rcv_skb+0x125/0x390 [ 31.079523] genl_rcv+0x24/0x40 [ 31.082794] netlink_unicast+0x437/0x610 [ 31.086830] netlink_sendmsg+0x62e/0xb80 [ 31.090862] sock_sendmsg+0xb5/0x100 [ 31.094558] ___sys_sendmsg+0x6c8/0x800 [ 31.098573] __sys_sendmsg+0xa3/0x120 [ 31.102380] SyS_sendmsg+0x27/0x40 [ 31.106004] do_syscall_64+0x1d5/0x640 [ 31.109866] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 31.115041] [ 31.116645] The buggy address belongs to the object at ffff8880aab46500 [ 31.116645] which belongs to the cache kmalloc-512 of size 512 [ 31.129292] The buggy address is located 216 bytes inside of [ 31.129292] 512-byte region [ffff8880aab46500, ffff8880aab46700) [ 31.141241] The buggy address belongs to the page: [ 31.146151] page:ffffea0002aad180 count:1 mapcount:0 mapping:ffff8880aab46000 index:0xffff8880aab46a00 [ 31.155662] flags: 0xfff00000000100(slab) [ 31.159788] raw: 00fff00000000100 ffff8880aab46000 ffff8880aab46a00 0000000100000001 [ 31.167657] raw: ffffea0002723e20 ffffea0002cf26a0 ffff88813fe80940 0000000000000000 [ 31.175552] page dumped because: kasan: bad access detected [ 31.181265] [ 31.182868] Memory state around the buggy address: [ 31.187878] ffff8880aab46480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.195320] ffff8880aab46500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.202656] >ffff8880aab46580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.210000] ^ [ 31.216227] ffff8880aab46600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.223563] ffff8880aab46680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.230897] ================================================================== [ 31.238324] Disabling lock debugging due to kernel taint [ 31.244216] Kernel panic - not syncing: panic_on_warn set ... [ 31.244216] [ 31.251583] CPU: 1 PID: 8095 Comm: syz-executor458 Tainted: G B 4.14.234-syzkaller #0 [ 31.260674] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.270024] Call Trace: [ 31.272611] dump_stack+0x1b2/0x281 [ 31.276234] panic+0x1f9/0x42d [ 31.279420] ? add_taint.cold+0x16/0x16 [ 31.283393] ? ___preempt_schedule+0x16/0x18 [ 31.287802] kasan_end_report+0x43/0x49 [ 31.291766] kasan_report_error.cold+0xa7/0x191 [ 31.296731] ? refcount_dec_not_one+0x9a/0xc0 [ 31.301207] __asan_report_load4_noabort+0x68/0x70 [ 31.306126] ? refcount_dec_not_one+0x9a/0xc0 [ 31.310618] refcount_dec_not_one+0x9a/0xc0 [ 31.314931] refcount_dec_and_mutex_lock+0x1a/0x60 [ 31.319844] nbd_genl_connect+0xf94/0x1400 [ 31.324412] ? nbd_xmit_timeout+0x500/0x500 [ 31.328742] ? validate_nla+0x192/0x5e0 [ 31.332697] genl_family_rcv_msg+0x572/0xb20 [ 31.337100] ? genl_rcv+0x40/0x40 [ 31.340549] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 31.345980] ? trace_hardirqs_on+0x10/0x10 [ 31.350191] ? sock_sendmsg+0xb5/0x100 [ 31.354060] genl_rcv_msg+0xaf/0x140 [ 31.357845] netlink_rcv_skb+0x125/0x390 [ 31.361885] ? genl_family_rcv_msg+0xb20/0xb20 [ 31.366462] ? netlink_ack+0x9a0/0x9a0 [ 31.370475] ? lock_acquire+0x170/0x3f0 [ 31.374430] genl_rcv+0x24/0x40 [ 31.377748] netlink_unicast+0x437/0x610 [ 31.381790] ? netlink_sendskb+0xd0/0xd0 [ 31.385850] ? __check_object_size+0x179/0x230 [ 31.390540] netlink_sendmsg+0x62e/0xb80 [ 31.394583] ? nlmsg_notify+0x170/0x170 [ 31.398539] ? kernel_recvmsg+0x210/0x210 [ 31.402671] ? security_socket_sendmsg+0x83/0xb0 [ 31.407407] ? nlmsg_notify+0x170/0x170 [ 31.411359] sock_sendmsg+0xb5/0x100 [ 31.415058] ___sys_sendmsg+0x6c8/0x800 [ 31.419023] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 31.423940] ? netlink_dump+0xad0/0xad0 [ 31.428375] ? nlmsg_notify+0x170/0x170 [ 31.432355] ? security_socket_recvmsg+0x8b/0xc0 [ 31.437177] ? SyS_recvfrom+0x27f/0x340 [ 31.441226] ? SyS_send+0x40/0x40 [ 31.444663] ? vm_insert_page+0x7c0/0x7c0 [ 31.448816] ? __fdget+0x167/0x1f0 [ 31.452425] ? sockfd_lookup_light+0xb2/0x160 [ 31.456926] __sys_sendmsg+0xa3/0x120 [ 31.460709] ? SyS_shutdown+0x160/0x160 [ 31.464667] ? up_read+0x17/0x30 [ 31.468014] ? __do_page_fault+0x159/0xad0 [ 31.472257] SyS_sendmsg+0x27/0x40 [ 31.475778] ? __sys_sendmsg+0x120/0x120 [ 31.479822] do_syscall_64+0x1d5/0x640 [ 31.483692] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 31.488947] RIP: 0033:0x4408d9 [ 31.492315] RSP: 002b:00007fff98e49a18 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 31.500003] RAX: ffffffffffffffda RBX: 00000000000077b3 RCX: 00000000004408d9 [ 31.507254] RDX: 0000000000000040 RSI: 0000000020000a00 RDI: 0000000000000004 [ 31.514611] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007fff98e49bb8 [ 31.521970] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff98e49a2c [ 31.529315] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 31.537453] Kernel Offset: disabled [ 31.541067] Rebooting in 86400 seconds..