Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.101' (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 syzkaller login: [ 73.117073][ T8656] ================================================================== [ 73.125571][ T8656] BUG: KASAN: use-after-free in refcount_dec_not_one+0x71/0x1e0 [ 73.133240][ T8656] Read of size 4 at addr ffff8880209251a0 by task syz-executor793/8656 [ 73.141489][ T8656] [ 73.143826][ T8656] CPU: 0 PID: 8656 Comm: syz-executor793 Not tainted 5.11.0-rc7-syzkaller #0 [ 73.152771][ T8656] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.162843][ T8656] Call Trace: [ 73.166127][ T8656] dump_stack+0x107/0x163 [ 73.170519][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.175807][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.181360][ T8656] print_address_description.constprop.0.cold+0x5b/0x2f8 [ 73.188409][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.193736][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.199026][ T8656] kasan_report.cold+0x79/0xd5 [ 73.203813][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.209114][ T8656] check_memory_region+0x13d/0x180 [ 73.214247][ T8656] refcount_dec_not_one+0x71/0x1e0 [ 73.219367][ T8656] ? refcount_warn_saturate+0x1e0/0x1e0 [ 73.224943][ T8656] ? nbd_config_put+0x5d0/0x8c0 [ 73.229829][ T8656] refcount_dec_and_mutex_lock+0x19/0x140 [ 73.235567][ T8656] nbd_genl_connect+0xee7/0x1560 [ 73.240581][ T8656] ? nbd_start_device+0xd40/0xd40 [ 73.247753][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.254015][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x1b7/0x280 [ 73.261403][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0xaf/0x280 [ 73.268703][ T8656] genl_family_rcv_msg_doit+0x228/0x320 [ 73.274280][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x280/0x280 [ 73.281782][ T8656] ? genl_op_from_small+0x23/0x3c0 [ 73.286908][ T8656] ? genl_get_cmd+0x3cf/0x480 [ 73.291607][ T8656] genl_rcv_msg+0x328/0x580 [ 73.296137][ T8656] ? genl_get_cmd+0x480/0x480 [ 73.300833][ T8656] ? nbd_start_device+0xd40/0xd40 [ 73.305872][ T8656] ? lock_release+0x710/0x710 [ 73.310565][ T8656] netlink_rcv_skb+0x153/0x420 [ 73.315396][ T8656] ? genl_get_cmd+0x480/0x480 [ 73.320138][ T8656] ? netlink_ack+0xaa0/0xaa0 [ 73.324747][ T8656] genl_rcv+0x24/0x40 [ 73.328737][ T8656] netlink_unicast+0x533/0x7d0 [ 73.333522][ T8656] ? netlink_attachskb+0x870/0x870 [ 73.338724][ T8656] ? _copy_from_iter_full+0x275/0x850 [ 73.344223][ T8656] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 73.350789][ T8656] ? __phys_addr_symbol+0x2c/0x70 [ 73.355909][ T8656] ? __sanitizer_cov_trace_cmp8+0x1d/0x70 [ 73.361652][ T8656] ? __check_object_size+0x171/0x3f0 [ 73.367082][ T8656] netlink_sendmsg+0x856/0xd90 [ 73.372012][ T8656] ? netlink_unicast+0x7d0/0x7d0 [ 73.377150][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.383417][ T8656] ? netlink_unicast+0x7d0/0x7d0 [ 73.388377][ T8656] sock_sendmsg+0xcf/0x120 [ 73.392815][ T8656] ____sys_sendmsg+0x6e8/0x810 [ 73.397617][ T8656] ? kernel_sendmsg+0x50/0x50 [ 73.402465][ T8656] ? do_recvmmsg+0x6c0/0x6c0 [ 73.407059][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.413307][ T8656] ? netlink_recvmsg+0x826/0xee0 [ 73.418256][ T8656] ___sys_sendmsg+0xf3/0x170 [ 73.422867][ T8656] ? sendmsg_copy_msghdr+0x160/0x160 [ 73.428170][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.434417][ T8656] ? security_socket_recvmsg+0x8f/0xc0 [ 73.439886][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.446321][ T8656] ? __sys_recvfrom+0x2cc/0x3a0 [ 73.451186][ T8656] ? __ia32_sys_send+0x100/0x100 [ 73.456130][ T8656] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80 [ 73.462404][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.468673][ T8656] ? __fget_light+0x215/0x280 [ 73.473390][ T8656] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 73.479660][ T8656] __sys_sendmsg+0xe5/0x1b0 [ 73.484179][ T8656] ? __sys_sendmsg_sock+0xb0/0xb0 [ 73.489209][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 73.495470][ T8656] ? syscall_enter_from_user_mode+0x1d/0x50 [ 73.501420][ T8656] do_syscall_64+0x2d/0x70 [ 73.505869][ T8656] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 73.511808][ T8656] RIP: 0033:0x440709 [ 73.515705][ T8656] 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 [ 73.535430][ T8656] RSP: 002b:00007ffd2323ebd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 73.543864][ T8656] RAX: ffffffffffffffda RBX: 0000000000011d10 RCX: 0000000000440709 [ 73.552881][ T8656] RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000003 [ 73.560853][ T8656] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffd2323ed78 [ 73.568924][ T8656] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd2323ebec [ 73.576919][ T8656] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 73.584909][ T8656] [ 73.587322][ T8656] Allocated by task 8653: [ 73.591764][ T8656] kasan_save_stack+0x1b/0x40 [ 73.596463][ T8656] ____kasan_kmalloc.constprop.0+0x82/0xa0 [ 73.602276][ T8656] nbd_dev_add+0x44/0x8e0 [ 73.606609][ T8656] nbd_genl_connect+0x59c/0x1560 [ 73.611552][ T8656] genl_family_rcv_msg_doit+0x228/0x320 [ 73.617108][ T8656] genl_rcv_msg+0x328/0x580 [ 73.621634][ T8656] netlink_rcv_skb+0x153/0x420 [ 73.626396][ T8656] genl_rcv+0x24/0x40 [ 73.630462][ T8656] netlink_unicast+0x533/0x7d0 [ 73.635257][ T8656] netlink_sendmsg+0x856/0xd90 [ 73.641334][ T8656] sock_sendmsg+0xcf/0x120 [ 73.645766][ T8656] ____sys_sendmsg+0x6e8/0x810 [ 73.650718][ T8656] ___sys_sendmsg+0xf3/0x170 [ 73.655334][ T8656] __sys_sendmsg+0xe5/0x1b0 [ 73.660443][ T8656] do_syscall_64+0x2d/0x70 [ 73.664861][ T8656] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 73.670867][ T8656] [ 73.673226][ T8656] Freed by task 8656: [ 73.677196][ T8656] kasan_save_stack+0x1b/0x40 [ 73.681887][ T8656] kasan_set_track+0x1c/0x30 [ 73.686497][ T8656] kasan_set_free_info+0x20/0x30 [ 73.691491][ T8656] ____kasan_slab_free+0xe1/0x110 [ 73.696519][ T8656] slab_free_freelist_hook+0x5d/0x150 [ 73.701897][ T8656] kfree+0xdb/0x3b0 [ 73.705717][ T8656] nbd_put.part.0+0x180/0x1d0 [ 73.710408][ T8656] nbd_config_put+0x6dd/0x8c0 [ 73.715149][ T8656] nbd_genl_connect+0xeb7/0x1560 [ 73.720085][ T8656] genl_family_rcv_msg_doit+0x228/0x320 [ 73.725681][ T8656] genl_rcv_msg+0x328/0x580 [ 73.730569][ T8656] netlink_rcv_skb+0x153/0x420 [ 73.735357][ T8656] genl_rcv+0x24/0x40 [ 73.739438][ T8656] netlink_unicast+0x533/0x7d0 [ 73.744285][ T8656] netlink_sendmsg+0x856/0xd90 [ 73.749055][ T8656] sock_sendmsg+0xcf/0x120 [ 73.753522][ T8656] ____sys_sendmsg+0x6e8/0x810 [ 73.758313][ T8656] ___sys_sendmsg+0xf3/0x170 [ 73.762900][ T8656] __sys_sendmsg+0xe5/0x1b0 [ 73.767415][ T8656] do_syscall_64+0x2d/0x70 [ 73.771916][ T8656] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 73.777838][ T8656] [ 73.780154][ T8656] The buggy address belongs to the object at ffff888020925000 [ 73.780154][ T8656] which belongs to the cache kmalloc-1k of size 1024 [ 73.794212][ T8656] The buggy address is located 416 bytes inside of [ 73.794212][ T8656] 1024-byte region [ffff888020925000, ffff888020925400) [ 73.807754][ T8656] The buggy address belongs to the page: [ 73.814560][ T8656] page:00000000e08a4339 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888020925800 pfn:0x20920 [ 73.826024][ T8656] head:00000000e08a4339 order:3 compound_mapcount:0 compound_pincount:0 [ 73.834376][ T8656] flags: 0xfff00000010200(slab|head) [ 73.839682][ T8656] raw: 00fff00000010200 ffffea0000740c00 0000000200000002 ffff888010c41140 [ 73.848269][ T8656] raw: ffff888020925800 000000008010000d 00000001ffffffff 0000000000000000 [ 73.856859][ T8656] page dumped because: kasan: bad access detected [ 73.863273][ T8656] [ 73.865645][ T8656] Memory state around the buggy address: [ 73.871358][ T8656] ffff888020925080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.879432][ T8656] ffff888020925100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.887492][ T8656] >ffff888020925180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.895566][ T8656] ^ [ 73.900710][ T8656] ffff888020925200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.909489][ T8656] ffff888020925280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.917565][ T8656] ================================================================== [ 73.925663][ T8656] Disabling lock debugging due to kernel taint [ 73.932684][ T8656] Kernel panic - not syncing: panic_on_warn set ... [ 73.939284][ T8656] CPU: 0 PID: 8656 Comm: syz-executor793 Tainted: G B 5.11.0-rc7-syzkaller #0 [ 73.949455][ T8656] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.959548][ T8656] Call Trace: [ 73.962839][ T8656] dump_stack+0x107/0x163 [ 73.967225][ T8656] ? refcount_dec_not_one+0x10/0x1e0 [ 73.972534][ T8656] panic+0x306/0x73d [ 73.976454][ T8656] ? __warn_printk+0xf3/0xf3 [ 73.981065][ T8656] ? preempt_schedule_common+0x59/0xc0 [ 73.986707][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 73.992161][ T8656] ? preempt_schedule_thunk+0x16/0x18 [ 73.998230][ T8656] ? trace_hardirqs_on+0x38/0x1c0 [ 74.003257][ T8656] ? trace_hardirqs_on+0x51/0x1c0 [ 74.008398][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 74.013944][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 74.019451][ T8656] end_report+0x58/0x5e [ 74.023629][ T8656] kasan_report.cold+0x67/0xd5 [ 74.028399][ T8656] ? refcount_dec_not_one+0x71/0x1e0 [ 74.033714][ T8656] check_memory_region+0x13d/0x180 [ 74.038844][ T8656] refcount_dec_not_one+0x71/0x1e0 [ 74.043976][ T8656] ? refcount_warn_saturate+0x1e0/0x1e0 [ 74.049522][ T8656] ? nbd_config_put+0x5d0/0x8c0 [ 74.054408][ T8656] refcount_dec_and_mutex_lock+0x19/0x140 [ 74.060126][ T8656] nbd_genl_connect+0xee7/0x1560 [ 74.065064][ T8656] ? nbd_start_device+0xd40/0xd40 [ 74.070093][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.076420][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x1b7/0x280 [ 74.083817][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0xaf/0x280 [ 74.091121][ T8656] genl_family_rcv_msg_doit+0x228/0x320 [ 74.096771][ T8656] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x280/0x280 [ 74.104220][ T8656] ? genl_op_from_small+0x23/0x3c0 [ 74.110271][ T8656] ? genl_get_cmd+0x3cf/0x480 [ 74.115005][ T8656] genl_rcv_msg+0x328/0x580 [ 74.119649][ T8656] ? genl_get_cmd+0x480/0x480 [ 74.124318][ T8656] ? nbd_start_device+0xd40/0xd40 [ 74.129354][ T8656] ? lock_release+0x710/0x710 [ 74.134072][ T8656] netlink_rcv_skb+0x153/0x420 [ 74.138840][ T8656] ? genl_get_cmd+0x480/0x480 [ 74.143507][ T8656] ? netlink_ack+0xaa0/0xaa0 [ 74.148107][ T8656] genl_rcv+0x24/0x40 [ 74.152084][ T8656] netlink_unicast+0x533/0x7d0 [ 74.157005][ T8656] ? netlink_attachskb+0x870/0x870 [ 74.162126][ T8656] ? _copy_from_iter_full+0x275/0x850 [ 74.167521][ T8656] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 74.173756][ T8656] ? __phys_addr_symbol+0x2c/0x70 [ 74.178778][ T8656] ? __sanitizer_cov_trace_cmp8+0x1d/0x70 [ 74.184508][ T8656] ? __check_object_size+0x171/0x3f0 [ 74.189800][ T8656] netlink_sendmsg+0x856/0xd90 [ 74.194765][ T8656] ? netlink_unicast+0x7d0/0x7d0 [ 74.199711][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.205974][ T8656] ? netlink_unicast+0x7d0/0x7d0 [ 74.210973][ T8656] sock_sendmsg+0xcf/0x120 [ 74.215406][ T8656] ____sys_sendmsg+0x6e8/0x810 [ 74.220269][ T8656] ? kernel_sendmsg+0x50/0x50 [ 74.224952][ T8656] ? do_recvmmsg+0x6c0/0x6c0 [ 74.229569][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.235918][ T8656] ? netlink_recvmsg+0x826/0xee0 [ 74.240858][ T8656] ___sys_sendmsg+0xf3/0x170 [ 74.245473][ T8656] ? sendmsg_copy_msghdr+0x160/0x160 [ 74.250760][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.257016][ T8656] ? security_socket_recvmsg+0x8f/0xc0 [ 74.262487][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.268740][ T8656] ? __sys_recvfrom+0x2cc/0x3a0 [ 74.273586][ T8656] ? __ia32_sys_send+0x100/0x100 [ 74.278563][ T8656] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80 [ 74.284803][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.291161][ T8656] ? __fget_light+0x215/0x280 [ 74.295947][ T8656] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 74.302216][ T8656] __sys_sendmsg+0xe5/0x1b0 [ 74.306811][ T8656] ? __sys_sendmsg_sock+0xb0/0xb0 [ 74.311840][ T8656] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 74.318207][ T8656] ? syscall_enter_from_user_mode+0x1d/0x50 [ 74.324126][ T8656] do_syscall_64+0x2d/0x70 [ 74.328545][ T8656] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 74.334441][ T8656] RIP: 0033:0x440709 [ 74.338345][ T8656] 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 [ 74.357959][ T8656] RSP: 002b:00007ffd2323ebd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 74.366484][ T8656] RAX: ffffffffffffffda RBX: 0000000000011d10 RCX: 0000000000440709 [ 74.374555][ T8656] RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000003 [ 74.382627][ T8656] RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffd2323ed78 [ 74.390596][ T8656] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd2323ebec [ 74.398573][ T8656] R13: 431bde82d7b634db R14: 00000000004ae018 R15: 00000000004004a0 [ 74.407354][ T8656] Kernel Offset: disabled [ 74.411688][ T8656] Rebooting in 86400 seconds..