[ 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 '10.128.0.81' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 89.415660] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program [ 89.466068] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 89.504680] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program executing program [ 89.554525] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program executing program [ 89.594688] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 89.625166] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program executing program [ 89.674833] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 89.704742] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program executing program [ 89.744884] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 89.775422] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. 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 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 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 [ 94.449172] nla_parse: 115 callbacks suppressed [ 94.449181] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. executing program [ 94.506851] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 94.520618] netlink: 4 bytes leftover after parsing attributes in process `syz-executor299'. [ 94.560667] ================================================================== [ 94.568240] BUG: KASAN: use-after-free in refcount_dec_not_one+0x71/0x1d0 [ 94.575152] Read of size 4 at addr ffff8880a4fa4158 by task syz-executor299/8970 [ 94.582661] [ 94.584273] CPU: 1 PID: 8970 Comm: syz-executor299 Not tainted 4.19.186-syzkaller #0 [ 94.592148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 94.602264] Call Trace: [ 94.604861] dump_stack+0x1fc/0x2ef [ 94.608471] print_address_description.cold+0x54/0x219 [ 94.613730] kasan_report_error.cold+0x8a/0x1b9 [ 94.618398] ? refcount_dec_not_one+0x71/0x1d0 [ 94.623002] kasan_report+0x8f/0xa0 [ 94.626616] ? refcount_dec_not_one+0x71/0x1d0 [ 94.631330] refcount_dec_not_one+0x71/0x1d0 [ 94.635738] ? refcount_dec_and_test_checked+0x20/0x20 [ 94.641010] ? nbd_config_put+0x5da/0x870 [ 94.645140] refcount_dec_and_mutex_lock+0x1c/0x80 [ 94.650072] nbd_genl_connect+0x11ee/0x1630 [ 94.654422] ? nbd_xmit_timeout+0x730/0x730 [ 94.658728] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 94.663917] ? validate_nla+0x270/0x820 [ 94.667874] ? nla_parse+0x1b2/0x290 [ 94.671589] genl_family_rcv_msg+0x642/0xc40 [ 94.676003] ? genl_rcv+0x40/0x40 [ 94.679465] ? genl_rcv_msg+0x12f/0x160 [ 94.683427] ? __mutex_add_waiter+0x160/0x160 [ 94.687910] ? __radix_tree_lookup+0x216/0x370 [ 94.692478] genl_rcv_msg+0xbf/0x160 [ 94.696174] netlink_rcv_skb+0x160/0x440 [ 94.700218] ? genl_family_rcv_msg+0xc40/0xc40 [ 94.704790] ? netlink_ack+0xae0/0xae0 [ 94.708668] ? genl_rcv+0x15/0x40 [ 94.712121] genl_rcv+0x24/0x40 [ 94.715383] netlink_unicast+0x4d5/0x690 [ 94.719432] ? netlink_sendskb+0x110/0x110 [ 94.724004] ? _copy_from_iter_full+0x229/0x7c0 [ 94.728653] ? __phys_addr_symbol+0x2c/0x70 [ 94.732968] ? __check_object_size+0x17b/0x3e0 [ 94.737539] netlink_sendmsg+0x6bb/0xc40 [ 94.741582] ? aa_af_perm+0x230/0x230 [ 94.745377] ? nlmsg_notify+0x1a0/0x1a0 [ 94.749350] ? kernel_recvmsg+0x220/0x220 [ 94.753496] ? nlmsg_notify+0x1a0/0x1a0 [ 94.757449] sock_sendmsg+0xc3/0x120 [ 94.761147] ___sys_sendmsg+0x7bb/0x8e0 [ 94.765111] ? copy_msghdr_from_user+0x440/0x440 [ 94.769844] ? netlink_dump+0xc10/0xc10 [ 94.773801] ? nlmsg_notify+0x1a0/0x1a0 [ 94.777773] ? security_socket_recvmsg+0x8f/0xc0 [ 94.782514] ? __sys_recvfrom+0x2cd/0x3a0 [ 94.786641] ? __ia32_sys_send+0x100/0x100 [ 94.790860] ? __fdget+0x1a0/0x230 [ 94.794380] __x64_sys_sendmsg+0x132/0x220 [ 94.798593] ? __sys_sendmsg+0x1b0/0x1b0 [ 94.802665] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 94.808011] ? trace_hardirqs_off_caller+0x6e/0x210 [ 94.813009] ? do_syscall_64+0x21/0x620 [ 94.816964] do_syscall_64+0xf9/0x620 [ 94.820749] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 94.825916] RIP: 0033:0x4406d9 [ 94.829110] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 94.848005] RSP: 002b:00007ffcecc19028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 94.855694] RAX: ffffffffffffffda RBX: 0000000000017103 RCX: 00000000004406d9 [ 94.862945] RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000003 [ 94.870195] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffcecc191c8 [ 94.877456] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcecc1903c [ 94.884722] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 94.892001] [ 94.893606] Allocated by task 8965: [ 94.897224] kmem_cache_alloc_trace+0x12f/0x380 [ 94.901870] nbd_dev_add+0x44/0x890 [ 94.905474] nbd_genl_connect+0x4cc/0x1630 [ 94.909688] genl_family_rcv_msg+0x642/0xc40 [ 94.914072] genl_rcv_msg+0xbf/0x160 [ 94.917761] netlink_rcv_skb+0x160/0x440 [ 94.921812] genl_rcv+0x24/0x40 [ 94.925068] netlink_unicast+0x4d5/0x690 [ 94.929103] netlink_sendmsg+0x6bb/0xc40 [ 94.933143] sock_sendmsg+0xc3/0x120 [ 94.936833] ___sys_sendmsg+0x7bb/0x8e0 [ 94.940783] __x64_sys_sendmsg+0x132/0x220 [ 94.945004] do_syscall_64+0xf9/0x620 [ 94.948783] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 94.953954] [ 94.955560] Freed by task 8970: [ 94.958816] kfree+0xcc/0x210 [ 94.961903] nbd_put.part.0+0xfe/0x140 [ 94.965768] nbd_config_put+0x6a0/0x870 [ 94.969719] nbd_genl_connect+0x11bb/0x1630 [ 94.974020] genl_family_rcv_msg+0x642/0xc40 [ 94.978402] genl_rcv_msg+0xbf/0x160 [ 94.982110] netlink_rcv_skb+0x160/0x440 [ 94.986147] genl_rcv+0x24/0x40 [ 94.989404] netlink_unicast+0x4d5/0x690 [ 94.993440] netlink_sendmsg+0x6bb/0xc40 [ 94.997478] sock_sendmsg+0xc3/0x120 [ 95.001169] ___sys_sendmsg+0x7bb/0x8e0 [ 95.005131] __x64_sys_sendmsg+0x132/0x220 [ 95.009343] do_syscall_64+0xf9/0x620 [ 95.013123] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 95.018289] [ 95.019899] The buggy address belongs to the object at ffff8880a4fa4080 [ 95.019899] which belongs to the cache kmalloc-512 of size 512 [ 95.032533] The buggy address is located 216 bytes inside of [ 95.032533] 512-byte region [ffff8880a4fa4080, ffff8880a4fa4280) [ 95.044395] The buggy address belongs to the page: [ 95.049312] page:ffffea000293e900 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 [ 95.057443] flags: 0xfff00000000100(slab) [ 95.061572] raw: 00fff00000000100 ffffea000292e588 ffffea000292cd48 ffff88813bff0940 [ 95.069442] raw: 0000000000000000 ffff8880a4fa4080 0000000100000006 0000000000000000 [ 95.077295] page dumped because: kasan: bad access detected [ 95.082979] [ 95.084581] Memory state around the buggy address: [ 95.089500] ffff8880a4fa4000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 95.096835] ffff8880a4fa4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.104173] >ffff8880a4fa4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.111506] ^ [ 95.117715] ffff8880a4fa4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.125054] ffff8880a4fa4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 95.132386] ================================================================== [ 95.139735] Disabling lock debugging due to kernel taint [ 95.159344] Kernel panic - not syncing: panic_on_warn set ... [ 95.159344] [ 95.166738] CPU: 1 PID: 8970 Comm: syz-executor299 Tainted: G B 4.19.186-syzkaller #0 [ 95.176001] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 95.185333] Call Trace: [ 95.187905] dump_stack+0x1fc/0x2ef [ 95.191619] panic+0x26a/0x50e [ 95.194788] ? __warn_printk+0xf3/0xf3 [ 95.198663] ? preempt_schedule_common+0x45/0xc0 [ 95.203395] ? ___preempt_schedule+0x16/0x18 [ 95.207781] ? trace_hardirqs_on+0x55/0x210 [ 95.212343] kasan_end_report+0x43/0x49 [ 95.216294] kasan_report_error.cold+0xa7/0x1b9 [ 95.220942] ? refcount_dec_not_one+0x71/0x1d0 [ 95.225502] kasan_report+0x8f/0xa0 [ 95.229107] ? refcount_dec_not_one+0x71/0x1d0 [ 95.233683] refcount_dec_not_one+0x71/0x1d0 [ 95.238070] ? refcount_dec_and_test_checked+0x20/0x20 [ 95.243340] ? nbd_config_put+0x5da/0x870 [ 95.247466] refcount_dec_and_mutex_lock+0x1c/0x80 [ 95.252375] nbd_genl_connect+0x11ee/0x1630 [ 95.256675] ? nbd_xmit_timeout+0x730/0x730 [ 95.260977] ? __sanitizer_cov_trace_switch+0x4b/0x80 [ 95.266156] ? validate_nla+0x270/0x820 [ 95.270110] ? nla_parse+0x1b2/0x290 [ 95.273801] genl_family_rcv_msg+0x642/0xc40 [ 95.278186] ? genl_rcv+0x40/0x40 [ 95.281613] ? genl_rcv_msg+0x12f/0x160 [ 95.285568] ? __mutex_add_waiter+0x160/0x160 [ 95.290064] ? __radix_tree_lookup+0x216/0x370 [ 95.294623] genl_rcv_msg+0xbf/0x160 [ 95.298315] netlink_rcv_skb+0x160/0x440 [ 95.302354] ? genl_family_rcv_msg+0xc40/0xc40 [ 95.306925] ? netlink_ack+0xae0/0xae0 [ 95.310791] ? genl_rcv+0x15/0x40 [ 95.314219] genl_rcv+0x24/0x40 [ 95.317474] netlink_unicast+0x4d5/0x690 [ 95.321513] ? netlink_sendskb+0x110/0x110 [ 95.325725] ? _copy_from_iter_full+0x229/0x7c0 [ 95.330381] ? __phys_addr_symbol+0x2c/0x70 [ 95.334692] ? __check_object_size+0x17b/0x3e0 [ 95.339257] netlink_sendmsg+0x6bb/0xc40 [ 95.343488] ? aa_af_perm+0x230/0x230 [ 95.347270] ? nlmsg_notify+0x1a0/0x1a0 [ 95.351230] ? kernel_recvmsg+0x220/0x220 [ 95.355354] ? nlmsg_notify+0x1a0/0x1a0 [ 95.359308] sock_sendmsg+0xc3/0x120 [ 95.363001] ___sys_sendmsg+0x7bb/0x8e0 [ 95.366953] ? copy_msghdr_from_user+0x440/0x440 [ 95.371684] ? netlink_dump+0xc10/0xc10 [ 95.375650] ? nlmsg_notify+0x1a0/0x1a0 [ 95.379606] ? security_socket_recvmsg+0x8f/0xc0 [ 95.384350] ? __sys_recvfrom+0x2cd/0x3a0 [ 95.388479] ? __ia32_sys_send+0x100/0x100 [ 95.392693] ? __fdget+0x1a0/0x230 [ 95.396209] __x64_sys_sendmsg+0x132/0x220 [ 95.400420] ? __sys_sendmsg+0x1b0/0x1b0 [ 95.404462] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 95.409803] ? trace_hardirqs_off_caller+0x6e/0x210 [ 95.414796] ? do_syscall_64+0x21/0x620 [ 95.418835] do_syscall_64+0xf9/0x620 [ 95.422626] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 95.427790] RIP: 0033:0x4406d9 [ 95.430962] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 95.449840] RSP: 002b:00007ffcecc19028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 95.457526] RAX: ffffffffffffffda RBX: 0000000000017103 RCX: 00000000004406d9 [ 95.464770] RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 0000000000000003 [ 95.472016] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffcecc191c8 [ 95.479276] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcecc1903c [ 95.486535] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 95.494453] Kernel Offset: disabled [ 95.498073] Rebooting in 86400 seconds..