[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 30.037254] kauditd_printk_skb: 7 callbacks suppressed [ 30.037265] audit: type=1800 audit(1545024684.003:29): pid=5968 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 30.062722] audit: type=1800 audit(1545024684.003:30): pid=5968 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.69' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 42.663539] ================================================================== [ 42.671026] BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 [ 42.677850] Read of size 2 at addr ffff8881bbe85474 by task syz-executor521/6127 [ 42.685357] [ 42.686970] CPU: 1 PID: 6127 Comm: syz-executor521 Not tainted 4.20.0-rc7+ #154 [ 42.694393] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.703723] Call Trace: [ 42.706292] dump_stack+0x244/0x39d [ 42.709927] ? dump_stack_print_info.cold.1+0x20/0x20 [ 42.715098] ? printk+0xa7/0xcf [ 42.718361] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 42.723097] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 42.728187] print_address_description.cold.7+0x9/0x1ff [ 42.733537] kasan_report.cold.8+0x242/0x309 [ 42.737948] ? tipc_group_bc_cong+0x327/0x3f0 [ 42.742426] __asan_report_load2_noabort+0x14/0x20 [ 42.747342] tipc_group_bc_cong+0x327/0x3f0 [ 42.751643] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 42.756745] ? tipc_group_cong+0x5d0/0x5d0 [ 42.760959] ? remove_wait_queue+0x1a6/0x360 [ 42.765364] ? add_wait_queue+0x2b0/0x2b0 [ 42.769493] ? __local_bh_enable_ip+0x160/0x260 [ 42.774177] tipc_send_group_bcast+0x50a/0xd90 [ 42.778751] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 42.783770] ? __init_waitqueue_head+0x150/0x150 [ 42.788511] ? refill_pi_state_cache.part.8+0x310/0x310 [ 42.793863] ? mark_held_locks+0x130/0x130 [ 42.798077] ? futex_wait_setup+0x266/0x3e0 [ 42.802387] ? futex_wake+0x760/0x760 [ 42.806171] ? print_usage_bug+0xc0/0xc0 [ 42.810223] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 42.815395] __tipc_sendmsg+0xeec/0x1d40 [ 42.819436] ? futex_wait+0x5ec/0xa50 [ 42.823228] ? tipc_sendmcast+0xf50/0xf50 [ 42.827375] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 42.832545] ? zap_class+0x640/0x640 [ 42.836237] ? print_usage_bug+0xc0/0xc0 [ 42.840276] ? find_held_lock+0x36/0x1c0 [ 42.844321] ? find_held_lock+0x36/0x1c0 [ 42.848366] ? mark_held_locks+0xc7/0x130 [ 42.852494] ? __local_bh_enable_ip+0x160/0x260 [ 42.857140] ? __local_bh_enable_ip+0x160/0x260 [ 42.861803] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 42.866370] ? trace_hardirqs_on+0xbd/0x310 [ 42.870690] ? lock_release+0xa00/0xa00 [ 42.874650] ? lock_sock_nested+0xe2/0x120 [ 42.878869] ? trace_hardirqs_off_caller+0x310/0x310 [ 42.883952] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 42.889479] ? check_preemption_disabled+0x48/0x280 [ 42.894477] ? lock_sock_nested+0x9a/0x120 [ 42.898693] ? lock_sock_nested+0x9a/0x120 [ 42.902912] ? __local_bh_enable_ip+0x160/0x260 [ 42.907566] tipc_sendmsg+0x50/0x70 [ 42.911175] ? __tipc_sendmsg+0x1d40/0x1d40 [ 42.915482] sock_sendmsg+0xd5/0x120 [ 42.919192] ___sys_sendmsg+0x7fd/0x930 [ 42.923169] ? find_held_lock+0x36/0x1c0 [ 42.927237] ? copy_msghdr_from_user+0x580/0x580 [ 42.931976] ? __fd_install+0x2b5/0x8f0 [ 42.935934] ? check_preemption_disabled+0x48/0x280 [ 42.940934] ? __fget_light+0x2e9/0x430 [ 42.944886] ? fget_raw+0x20/0x20 [ 42.948338] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 42.953853] ? __fd_install+0x2f9/0x8f0 [ 42.957813] ? get_unused_fd_flags+0x1a0/0x1a0 [ 42.962378] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 42.967898] ? sockfd_lookup_light+0xc5/0x160 [ 42.972379] __sys_sendmsg+0x11d/0x280 [ 42.976253] ? __ia32_sys_shutdown+0x80/0x80 [ 42.980646] ? __x64_sys_futex+0x47f/0x6a0 [ 42.984901] ? do_syscall_64+0x9a/0x820 [ 42.988859] ? do_syscall_64+0x9a/0x820 [ 42.992831] ? trace_hardirqs_off_caller+0x310/0x310 [ 42.997942] __x64_sys_sendmsg+0x78/0xb0 [ 43.001989] do_syscall_64+0x1b9/0x820 [ 43.005857] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 43.011203] ? syscall_return_slowpath+0x5e0/0x5e0 [ 43.016120] ? trace_hardirqs_on_caller+0x310/0x310 [ 43.021117] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 43.026119] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 43.032768] ? __switch_to_asm+0x40/0x70 [ 43.036810] ? __switch_to_asm+0x34/0x70 [ 43.040855] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.045697] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.050871] RIP: 0033:0x446389 [ 43.054050] Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 43.072948] RSP: 002b:00007f6fd6d0adb8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 43.080638] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 43.087891] RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000005 [ 43.095141] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 43.102389] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 43.109641] R13: 00007ffc5491f04f R14: 00007f6fd6d0b9c0 R15: 00000000006dad2c [ 43.116899] [ 43.118509] Allocated by task 6128: [ 43.122121] save_stack+0x43/0xd0 [ 43.125579] kasan_kmalloc+0xc7/0xe0 [ 43.129291] kmem_cache_alloc_trace+0x152/0x750 [ 43.133946] tipc_group_create+0x152/0xa70 [ 43.138297] tipc_setsockopt+0x2d1/0xd70 [ 43.142340] __sys_setsockopt+0x1ba/0x3c0 [ 43.146475] __x64_sys_setsockopt+0xbe/0x150 [ 43.150866] do_syscall_64+0x1b9/0x820 [ 43.154733] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.159895] [ 43.161516] Freed by task 6128: [ 43.164790] save_stack+0x43/0xd0 [ 43.168387] __kasan_slab_free+0x102/0x150 [ 43.172601] kasan_slab_free+0xe/0x10 [ 43.176384] kfree+0xcf/0x230 [ 43.179472] tipc_group_delete+0x2e4/0x3f0 [ 43.183688] tipc_sk_leave+0x113/0x220 [ 43.187557] tipc_setsockopt+0x97d/0xd70 [ 43.191600] __sys_setsockopt+0x1ba/0x3c0 [ 43.195744] __x64_sys_setsockopt+0xbe/0x150 [ 43.200135] do_syscall_64+0x1b9/0x820 [ 43.204001] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.209164] [ 43.210776] The buggy address belongs to the object at ffff8881bbe85400 [ 43.210776] which belongs to the cache kmalloc-192 of size 192 [ 43.223410] The buggy address is located 116 bytes inside of [ 43.223410] 192-byte region [ffff8881bbe85400, ffff8881bbe854c0) [ 43.235259] The buggy address belongs to the page: [ 43.240170] page:ffffea0006efa140 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 [ 43.248290] flags: 0x2fffc0000000200(slab) [ 43.252507] raw: 02fffc0000000200 ffffea0006ee9908 ffffea00072dc548 ffff8881da800040 [ 43.260371] raw: 0000000000000000 ffff8881bbe85000 0000000100000010 0000000000000000 [ 43.268229] page dumped because: kasan: bad access detected [ 43.273914] [ 43.275518] Memory state around the buggy address: [ 43.280427] ffff8881bbe85300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.287773] ffff8881bbe85380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 43.295126] >ffff8881bbe85400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.302597] ^ [ 43.309591] ffff8881bbe85480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 43.316944] ffff8881bbe85500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 43.324280] ================================================================== [ 43.331614] Disabling lock debugging due to kernel taint [ 43.337512] Kernel panic - not syncing: panic_on_warn set ... [ 43.343414] CPU: 1 PID: 6127 Comm: syz-executor521 Tainted: G B 4.20.0-rc7+ #154 [ 43.352271] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.361612] Call Trace: [ 43.364179] dump_stack+0x244/0x39d [ 43.367797] ? dump_stack_print_info.cold.1+0x20/0x20 [ 43.372971] panic+0x2ad/0x55c [ 43.376145] ? add_taint.cold.5+0x16/0x16 [ 43.380274] ? preempt_schedule+0x4d/0x60 [ 43.384402] ? ___preempt_schedule+0x16/0x18 [ 43.388796] ? trace_hardirqs_on+0xb4/0x310 [ 43.393119] kasan_end_report+0x47/0x4f [ 43.397073] kasan_report.cold.8+0x76/0x309 [ 43.401372] ? tipc_group_bc_cong+0x327/0x3f0 [ 43.405873] __asan_report_load2_noabort+0x14/0x20 [ 43.410784] tipc_group_bc_cong+0x327/0x3f0 [ 43.415091] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 43.420182] ? tipc_group_cong+0x5d0/0x5d0 [ 43.424398] ? remove_wait_queue+0x1a6/0x360 [ 43.428946] ? add_wait_queue+0x2b0/0x2b0 [ 43.433236] ? __local_bh_enable_ip+0x160/0x260 [ 43.437894] tipc_send_group_bcast+0x50a/0xd90 [ 43.442480] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 43.447783] ? __init_waitqueue_head+0x150/0x150 [ 43.452527] ? refill_pi_state_cache.part.8+0x310/0x310 [ 43.457877] ? mark_held_locks+0x130/0x130 [ 43.462093] ? futex_wait_setup+0x266/0x3e0 [ 43.466411] ? futex_wake+0x760/0x760 [ 43.470188] ? print_usage_bug+0xc0/0xc0 [ 43.474243] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 43.479577] __tipc_sendmsg+0xeec/0x1d40 [ 43.483675] ? futex_wait+0x5ec/0xa50 [ 43.487488] ? tipc_sendmcast+0xf50/0xf50 [ 43.491620] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 43.496793] ? zap_class+0x640/0x640 [ 43.500710] ? print_usage_bug+0xc0/0xc0 [ 43.504759] ? find_held_lock+0x36/0x1c0 [ 43.508803] ? find_held_lock+0x36/0x1c0 [ 43.512850] ? mark_held_locks+0xc7/0x130 [ 43.517092] ? __local_bh_enable_ip+0x160/0x260 [ 43.522040] ? __local_bh_enable_ip+0x160/0x260 [ 43.526697] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 43.531263] ? trace_hardirqs_on+0xbd/0x310 [ 43.535595] ? lock_release+0xa00/0xa00 [ 43.539554] ? lock_sock_nested+0xe2/0x120 [ 43.543861] ? trace_hardirqs_off_caller+0x310/0x310 [ 43.549108] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 43.554758] ? check_preemption_disabled+0x48/0x280 [ 43.560035] ? lock_sock_nested+0x9a/0x120 [ 43.564390] ? lock_sock_nested+0x9a/0x120 [ 43.568621] ? __local_bh_enable_ip+0x160/0x260 [ 43.573411] tipc_sendmsg+0x50/0x70 [ 43.577046] ? __tipc_sendmsg+0x1d40/0x1d40 [ 43.581575] sock_sendmsg+0xd5/0x120 [ 43.585425] ___sys_sendmsg+0x7fd/0x930 [ 43.589566] ? find_held_lock+0x36/0x1c0 [ 43.593624] ? copy_msghdr_from_user+0x580/0x580 [ 43.598389] ? __fd_install+0x2b5/0x8f0 [ 43.602467] ? check_preemption_disabled+0x48/0x280 [ 43.607605] ? __fget_light+0x2e9/0x430 [ 43.611714] ? fget_raw+0x20/0x20 [ 43.615159] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 43.620805] ? __fd_install+0x2f9/0x8f0 [ 43.624769] ? get_unused_fd_flags+0x1a0/0x1a0 [ 43.629338] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 43.634998] ? sockfd_lookup_light+0xc5/0x160 [ 43.639485] __sys_sendmsg+0x11d/0x280 [ 43.643361] ? __ia32_sys_shutdown+0x80/0x80 [ 43.647818] ? __x64_sys_futex+0x47f/0x6a0 [ 43.652038] ? do_syscall_64+0x9a/0x820 [ 43.655997] ? do_syscall_64+0x9a/0x820 [ 43.659980] ? trace_hardirqs_off_caller+0x310/0x310 [ 43.665110] __x64_sys_sendmsg+0x78/0xb0 [ 43.669160] do_syscall_64+0x1b9/0x820 [ 43.673136] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 43.678502] ? syscall_return_slowpath+0x5e0/0x5e0 [ 43.683768] ? trace_hardirqs_on_caller+0x310/0x310 [ 43.688889] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 43.693892] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 43.700547] ? __switch_to_asm+0x40/0x70 [ 43.704595] ? __switch_to_asm+0x34/0x70 [ 43.708746] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.713684] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.718988] RIP: 0033:0x446389 [ 43.722169] Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 43.741054] RSP: 002b:00007f6fd6d0adb8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 43.748845] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 43.756218] RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000005 [ 43.763505] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 43.770758] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 43.778008] R13: 00007ffc5491f04f R14: 00007f6fd6d0b9c0 R15: 00000000006dad2c [ 43.786372] Kernel Offset: disabled [ 43.790034] Rebooting in 86400 seconds..