[ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.41' (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 syzkaller login: [ 31.652955] ================================================================== [ 31.660465] BUG: KASAN: use-after-free in refcount_dec_not_one+0x9a/0xc0 [ 31.667337] Read of size 4 at addr ffff8880a98ecd98 by task syz-executor882/8132 [ 31.675016] [ 31.676642] CPU: 0 PID: 8132 Comm: syz-executor882 Not tainted 4.14.229-syzkaller #0 [ 31.684741] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.694094] Call Trace: [ 31.696686] dump_stack+0x1b2/0x281 [ 31.700338] print_address_description.cold+0x54/0x1d3 [ 31.705632] kasan_report_error.cold+0x8a/0x191 [ 31.710350] ? refcount_dec_not_one+0x9a/0xc0 [ 31.714853] __asan_report_load4_noabort+0x68/0x70 [ 31.719878] ? refcount_dec_not_one+0x9a/0xc0 [ 31.724392] refcount_dec_not_one+0x9a/0xc0 [ 31.728723] refcount_dec_and_mutex_lock+0x1a/0x60 [ 31.733868] nbd_genl_connect+0xf94/0x1400 [ 31.738123] ? nbd_xmit_timeout+0x500/0x500 [ 31.742464] ? __mutex_lock+0x356/0x1310 [ 31.746536] ? validate_nla+0x192/0x5e0 [ 31.750523] ? nla_parse+0x157/0x1f0 [ 31.754229] genl_family_rcv_msg+0x572/0xb20 [ 31.758646] ? genl_rcv+0x40/0x40 [ 31.762090] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 31.767550] ? trace_hardirqs_on+0x10/0x10 [ 31.771802] ? sock_sendmsg+0xb5/0x100 [ 31.775699] genl_rcv_msg+0xaf/0x140 [ 31.779424] netlink_rcv_skb+0x125/0x390 [ 31.783498] ? genl_family_rcv_msg+0xb20/0xb20 [ 31.788116] ? netlink_ack+0x9a0/0x9a0 [ 31.792008] ? lock_acquire+0x170/0x3f0 [ 31.796137] genl_rcv+0x24/0x40 [ 31.799422] netlink_unicast+0x437/0x610 [ 31.803526] ? netlink_sendskb+0xd0/0xd0 [ 31.807876] ? __check_object_size+0x179/0x230 [ 31.812509] netlink_sendmsg+0x62e/0xb80 [ 31.816597] ? nlmsg_notify+0x170/0x170 [ 31.821169] ? kernel_recvmsg+0x210/0x210 [ 31.825456] ? security_socket_sendmsg+0x83/0xb0 [ 31.830283] ? nlmsg_notify+0x170/0x170 [ 31.834626] sock_sendmsg+0xb5/0x100 [ 31.838376] ___sys_sendmsg+0x6c8/0x800 [ 31.842394] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 31.847211] ? netlink_dump+0xad0/0xad0 [ 31.851384] ? nlmsg_notify+0x170/0x170 [ 31.855422] ? security_socket_recvmsg+0x8b/0xc0 [ 31.860219] ? SyS_recvfrom+0x27f/0x340 [ 31.864218] ? SyS_send+0x40/0x40 [ 31.867687] ? vm_insert_page+0x7c0/0x7c0 [ 31.871837] ? __fdget+0x167/0x1f0 [ 31.875381] ? sockfd_lookup_light+0xb2/0x160 [ 31.879879] __sys_sendmsg+0xa3/0x120 [ 31.883681] ? SyS_shutdown+0x160/0x160 [ 31.887687] ? up_read+0x17/0x30 [ 31.891092] ? __do_page_fault+0x159/0xad0 [ 31.895344] SyS_sendmsg+0x27/0x40 [ 31.898905] ? __sys_sendmsg+0x120/0x120 [ 31.902969] do_syscall_64+0x1d5/0x640 [ 31.906887] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 31.912074] RIP: 0033:0x4407b9 [ 31.915273] RSP: 002b:00007ffc95f18408 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 31.923008] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00000000004407b9 [ 31.930298] RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003 [ 31.937588] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 31.944879] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000007977 [ 31.952365] R13: 00007ffc95f1841c R14: 00007ffc95f18430 R15: 00007ffc95f18420 [ 31.959758] [ 31.961376] Allocated by task 8153: [ 31.965262] kasan_kmalloc+0xeb/0x160 [ 31.969108] kmem_cache_alloc_trace+0x131/0x3d0 [ 31.973809] nbd_dev_add+0x7c/0x800 [ 31.977475] nbd_genl_connect+0x3a4/0x1400 [ 31.982056] genl_family_rcv_msg+0x572/0xb20 [ 31.986471] genl_rcv_msg+0xaf/0x140 [ 31.990273] netlink_rcv_skb+0x125/0x390 [ 31.994343] genl_rcv+0x24/0x40 [ 31.997898] netlink_unicast+0x437/0x610 [ 32.001969] netlink_sendmsg+0x62e/0xb80 [ 32.006094] sock_sendmsg+0xb5/0x100 [ 32.009811] ___sys_sendmsg+0x6c8/0x800 [ 32.013804] __sys_sendmsg+0xa3/0x120 [ 32.018243] SyS_sendmsg+0x27/0x40 [ 32.021802] do_syscall_64+0x1d5/0x640 [ 32.025745] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 32.031045] [ 32.032804] Freed by task 8132: [ 32.036372] kasan_slab_free+0xc3/0x1a0 [ 32.045353] kfree+0xc9/0x250 [ 32.049138] nbd_put.part.0+0x100/0x140 [ 32.053208] nbd_config_put+0x62a/0x810 [ 32.057212] nbd_genl_connect+0xf6c/0x1400 [ 32.062000] genl_family_rcv_msg+0x572/0xb20 [ 32.066433] genl_rcv_msg+0xaf/0x140 [ 32.070372] netlink_rcv_skb+0x125/0x390 [ 32.074738] genl_rcv+0x24/0x40 [ 32.078223] netlink_unicast+0x437/0x610 [ 32.082430] netlink_sendmsg+0x62e/0xb80 [ 32.086612] sock_sendmsg+0xb5/0x100 [ 32.090786] ___sys_sendmsg+0x6c8/0x800 [ 32.095234] __sys_sendmsg+0xa3/0x120 [ 32.099187] SyS_sendmsg+0x27/0x40 [ 32.102916] do_syscall_64+0x1d5/0x640 [ 32.107099] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 32.112328] [ 32.113965] The buggy address belongs to the object at ffff8880a98eccc0 [ 32.113965] which belongs to the cache kmalloc-512 of size 512 [ 32.128161] The buggy address is located 216 bytes inside of [ 32.128161] 512-byte region [ffff8880a98eccc0, ffff8880a98ecec0) [ 32.140400] The buggy address belongs to the page: [ 32.145451] page:ffffea0002a63b00 count:1 mapcount:0 mapping:ffff8880a98ec040 index:0x0 [ 32.154367] flags: 0xfff00000000100(slab) [ 32.158551] raw: 00fff00000000100 ffff8880a98ec040 0000000000000000 0000000100000006 [ 32.166687] raw: ffffea0002ab02e0 ffffea0002d17c20 ffff88813fe80940 0000000000000000 [ 32.174706] page dumped because: kasan: bad access detected [ 32.180418] [ 32.182052] Memory state around the buggy address: [ 32.187137] ffff8880a98ecc80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 32.194520] ffff8880a98ecd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.201884] >ffff8880a98ecd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.209368] ^ [ 32.213523] ffff8880a98ece00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.220905] ffff8880a98ece80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 32.228327] ================================================================== [ 32.235888] Disabling lock debugging due to kernel taint [ 32.247871] Kernel panic - not syncing: panic_on_warn set ... [ 32.247871] [ 32.255260] CPU: 0 PID: 8132 Comm: syz-executor882 Tainted: G B 4.14.229-syzkaller #0 [ 32.264353] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.273710] Call Trace: [ 32.276312] dump_stack+0x1b2/0x281 [ 32.280669] panic+0x1f9/0x42d [ 32.283967] ? add_taint.cold+0x16/0x16 [ 32.288083] ? ___preempt_schedule+0x16/0x18 [ 32.292508] kasan_end_report+0x43/0x49 [ 32.296492] kasan_report_error.cold+0xa7/0x191 [ 32.301171] ? refcount_dec_not_one+0x9a/0xc0 [ 32.305680] __asan_report_load4_noabort+0x68/0x70 [ 32.310759] ? refcount_dec_not_one+0x9a/0xc0 [ 32.315269] refcount_dec_not_one+0x9a/0xc0 [ 32.319599] refcount_dec_and_mutex_lock+0x1a/0x60 [ 32.324759] nbd_genl_connect+0xf94/0x1400 [ 32.329018] ? nbd_xmit_timeout+0x500/0x500 [ 32.333332] ? __mutex_lock+0x356/0x1310 [ 32.337771] ? validate_nla+0x192/0x5e0 [ 32.341750] ? nla_parse+0x157/0x1f0 [ 32.345479] genl_family_rcv_msg+0x572/0xb20 [ 32.349983] ? genl_rcv+0x40/0x40 [ 32.353813] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 32.368337] ? trace_hardirqs_on+0x10/0x10 [ 32.375711] ? sock_sendmsg+0xb5/0x100 [ 32.383554] genl_rcv_msg+0xaf/0x140 [ 32.389190] netlink_rcv_skb+0x125/0x390 [ 32.394099] ? genl_family_rcv_msg+0xb20/0xb20 [ 32.399316] ? netlink_ack+0x9a0/0x9a0 [ 32.403199] ? lock_acquire+0x170/0x3f0 [ 32.407179] genl_rcv+0x24/0x40 [ 32.410465] netlink_unicast+0x437/0x610 [ 32.414545] ? netlink_sendskb+0xd0/0xd0 [ 32.418618] ? __check_object_size+0x179/0x230 [ 32.428167] netlink_sendmsg+0x62e/0xb80 [ 32.440398] ? nlmsg_notify+0x170/0x170 [ 32.444981] ? kernel_recvmsg+0x210/0x210 [ 32.450675] ? security_socket_sendmsg+0x83/0xb0 [ 32.457397] ? nlmsg_notify+0x170/0x170 [ 32.462283] sock_sendmsg+0xb5/0x100 [ 32.468066] ___sys_sendmsg+0x6c8/0x800 [ 32.473851] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 32.483703] ? netlink_dump+0xad0/0xad0 [ 32.490726] ? nlmsg_notify+0x170/0x170 [ 32.495201] ? security_socket_recvmsg+0x8b/0xc0 [ 32.499982] ? SyS_recvfrom+0x27f/0x340 [ 32.504189] ? SyS_send+0x40/0x40 [ 32.507695] ? vm_insert_page+0x7c0/0x7c0 [ 32.513099] ? __fdget+0x167/0x1f0 [ 32.516683] ? sockfd_lookup_light+0xb2/0x160 [ 32.521293] __sys_sendmsg+0xa3/0x120 [ 32.525111] ? SyS_shutdown+0x160/0x160 [ 32.529157] ? up_read+0x17/0x30 [ 32.532578] ? __do_page_fault+0x159/0xad0 [ 32.536972] SyS_sendmsg+0x27/0x40 [ 32.540537] ? __sys_sendmsg+0x120/0x120 [ 32.544618] do_syscall_64+0x1d5/0x640 [ 32.548524] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 32.553727] RIP: 0033:0x4407b9 [ 32.556914] RSP: 002b:00007ffc95f18408 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 32.564626] RAX: ffffffffffffffda RBX: 00000000000f4240 RCX: 00000000004407b9 [ 32.571889] RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003 [ 32.579176] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 [ 32.586468] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000007977 [ 32.593834] R13: 00007ffc95f1841c R14: 00007ffc95f18430 R15: 00007ffc95f18420 [ 32.601675] Kernel Offset: disabled [ 32.605412] Rebooting in 86400 seconds..