[....] 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. [ 29.636843] kauditd_printk_skb: 8 callbacks suppressed [ 29.636857] audit: type=1800 audit(1545120296.025:29): pid=5900 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 29.669406] audit: type=1800 audit(1545120296.025:30): pid=5900 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 33.523868] sshd (6039) used greatest stack depth: 15744 bytes left Warning: Permanently added '10.128.0.80' (ECDSA) to the list of known hosts. executing program [ 40.570245] ================================================================== [ 40.577753] BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 [ 40.584580] Read of size 2 at addr ffff8881d877a974 by task syz-executor108/6058 [ 40.592093] [ 40.593718] CPU: 1 PID: 6058 Comm: syz-executor108 Not tainted 4.20.0-rc7+ #376 [ 40.601160] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.610512] Call Trace: [ 40.613086] dump_stack+0x244/0x39d [ 40.616703] ? dump_stack_print_info.cold.1+0x20/0x20 [ 40.621882] ? printk+0xa7/0xcf [ 40.625163] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 40.629909] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 40.635005] print_address_description.cold.7+0x9/0x1ff [ 40.640358] kasan_report.cold.8+0x242/0x309 [ 40.644756] ? tipc_group_bc_cong+0x327/0x3f0 [ 40.649237] __asan_report_load2_noabort+0x14/0x20 [ 40.654238] tipc_group_bc_cong+0x327/0x3f0 [ 40.658547] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 40.663646] ? tipc_group_cong+0x5d0/0x5d0 [ 40.667882] ? remove_wait_queue+0x1a6/0x360 [ 40.672281] ? add_wait_queue+0x2b0/0x2b0 [ 40.676422] ? __local_bh_enable_ip+0x160/0x260 [ 40.681081] tipc_send_group_bcast+0x50a/0xd90 [ 40.685673] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 40.690701] ? __init_waitqueue_head+0x150/0x150 [ 40.695453] ? mark_held_locks+0x130/0x130 [ 40.699676] ? __might_sleep+0x95/0x190 [ 40.703642] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 40.709169] ? futex_wait_queue_me+0x55d/0x840 [ 40.713764] ? refill_pi_state_cache.part.8+0x310/0x310 [ 40.719131] ? print_usage_bug+0xc0/0xc0 [ 40.723192] __tipc_sendmsg+0xeec/0x1d40 [ 40.727265] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 40.732806] ? get_futex_value_locked+0xcb/0xf0 [ 40.737481] ? tipc_sendmcast+0xf50/0xf50 [ 40.741616] ? futex_wake+0x760/0x760 [ 40.745404] ? __lock_acquire+0x62f/0x4c20 [ 40.749625] ? zap_class+0x640/0x640 [ 40.753333] ? print_usage_bug+0xc0/0xc0 [ 40.757409] ? find_held_lock+0x36/0x1c0 [ 40.761491] ? mark_held_locks+0xc7/0x130 [ 40.765626] ? __local_bh_enable_ip+0x160/0x260 [ 40.770294] ? __local_bh_enable_ip+0x160/0x260 [ 40.774994] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 40.779566] ? trace_hardirqs_on+0xbd/0x310 [ 40.783875] ? lock_release+0xa00/0xa00 [ 40.787838] ? lock_sock_nested+0xe2/0x120 [ 40.792074] ? trace_hardirqs_off_caller+0x310/0x310 [ 40.797167] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 40.802695] ? check_preemption_disabled+0x48/0x280 [ 40.807701] ? lock_sock_nested+0x9a/0x120 [ 40.811942] ? lock_sock_nested+0x9a/0x120 [ 40.816168] ? __local_bh_enable_ip+0x160/0x260 [ 40.820908] tipc_sendmsg+0x50/0x70 [ 40.824524] ? __tipc_sendmsg+0x1d40/0x1d40 [ 40.828846] sock_sendmsg+0xd5/0x120 [ 40.832548] ___sys_sendmsg+0x51d/0x930 [ 40.836513] ? zap_class+0x640/0x640 [ 40.840218] ? copy_msghdr_from_user+0x580/0x580 [ 40.844966] ? find_held_lock+0x36/0x1c0 [ 40.849036] ? __fget_light+0x2e9/0x430 [ 40.853002] ? fget_raw+0x20/0x20 [ 40.856445] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 40.861014] ? trace_hardirqs_on+0xbd/0x310 [ 40.865348] ? _raw_spin_unlock_bh+0x30/0x40 [ 40.869745] ? trace_hardirqs_off_caller+0x310/0x310 [ 40.874841] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 40.880384] ? check_preemption_disabled+0x48/0x280 [ 40.885390] ? release_sock+0x1ec/0x2c0 [ 40.889351] ? release_sock+0x1ec/0x2c0 [ 40.893322] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 40.898853] ? sockfd_lookup_light+0xc5/0x160 [ 40.903356] __sys_sendmmsg+0x246/0x6d0 [ 40.907331] ? __ia32_sys_sendmsg+0xb0/0xb0 [ 40.911643] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 40.917168] ? rcvbuf_limit+0x2c0/0x2c0 [ 40.921135] ? aa_sock_opt_perm.isra.13+0xa1/0x130 [ 40.926063] ? __x64_sys_futex+0x47f/0x6a0 [ 40.930298] ? do_syscall_64+0x9a/0x820 [ 40.934270] ? do_syscall_64+0x9a/0x820 [ 40.938239] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 40.942824] ? trace_hardirqs_on+0xbd/0x310 [ 40.947142] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 40.952498] ? trace_hardirqs_off_caller+0x310/0x310 [ 40.957593] __x64_sys_sendmmsg+0x9d/0x100 [ 40.961822] do_syscall_64+0x1b9/0x820 [ 40.965704] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 40.971077] ? syscall_return_slowpath+0x5e0/0x5e0 [ 40.975998] ? trace_hardirqs_on_caller+0x310/0x310 [ 40.981001] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 40.986006] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 40.992708] ? __switch_to_asm+0x40/0x70 [ 40.996774] ? __switch_to_asm+0x34/0x70 [ 41.000824] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.005665] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 41.010844] RIP: 0033:0x446339 [ 41.014040] 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 [ 41.032944] RSP: 002b:00007f15687d7db8 EFLAGS: 00000297 ORIG_RAX: 0000000000000133 [ 41.040640] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446339 [ 41.047924] RDX: 0000000000000142 RSI: 0000000020000000 RDI: 0000000000000006 [ 41.055193] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 41.062444] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 41.069698] R13: 00007ffe412e39af R14: 00007f15687d89c0 R15: 00000000006dad2c [ 41.076958] [ 41.078579] Allocated by task 6058: [ 41.082193] save_stack+0x43/0xd0 [ 41.085631] kasan_kmalloc+0xc7/0xe0 [ 41.089338] kmem_cache_alloc_trace+0x152/0x750 [ 41.094012] tipc_group_create+0x152/0xa70 [ 41.098244] tipc_setsockopt+0x2d1/0xd70 [ 41.102292] __sys_setsockopt+0x1ba/0x3c0 [ 41.106459] __x64_sys_setsockopt+0xbe/0x150 [ 41.110892] do_syscall_64+0x1b9/0x820 [ 41.114799] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 41.119966] [ 41.121578] Freed by task 6059: [ 41.124866] save_stack+0x43/0xd0 [ 41.124903] __kasan_slab_free+0x102/0x150 [ 41.124921] kasan_slab_free+0xe/0x10 [ 41.133121] kfree+0xcf/0x230 [ 41.140008] tipc_group_delete+0x2e4/0x3f0 [ 41.144253] tipc_sk_leave+0x113/0x220 [ 41.148147] tipc_setsockopt+0x97d/0xd70 [ 41.152216] __sys_setsockopt+0x1ba/0x3c0 [ 41.156373] __x64_sys_setsockopt+0xbe/0x150 [ 41.160791] do_syscall_64+0x1b9/0x820 [ 41.164714] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 41.169931] [ 41.171555] The buggy address belongs to the object at ffff8881d877a900 [ 41.171555] which belongs to the cache kmalloc-192 of size 192 [ 41.184211] The buggy address is located 116 bytes inside of [ 41.184211] 192-byte region [ffff8881d877a900, ffff8881d877a9c0) [ 41.196064] The buggy address belongs to the page: [ 41.200980] page:ffffea000761de80 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 [ 41.209102] flags: 0x2fffc0000000200(slab) [ 41.213329] raw: 02fffc0000000200 ffffea000761edc8 ffffea00075dc188 ffff8881da800040 [ 41.221197] raw: 0000000000000000 ffff8881d877a000 0000000100000010 0000000000000000 [ 41.229059] page dumped because: kasan: bad access detected [ 41.234747] [ 41.236355] Memory state around the buggy address: [ 41.241267] ffff8881d877a800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.248627] ffff8881d877a880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 41.255971] >ffff8881d877a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.263318] ^ [ 41.270324] ffff8881d877a980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 41.277671] ffff8881d877aa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 41.285054] ================================================================== [ 41.292395] Disabling lock debugging due to kernel taint [ 41.298123] Kernel panic - not syncing: panic_on_warn set ... [ 41.304024] CPU: 1 PID: 6058 Comm: syz-executor108 Tainted: G B 4.20.0-rc7+ #376 [ 41.312844] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.322180] Call Trace: [ 41.324752] dump_stack+0x244/0x39d [ 41.328367] ? dump_stack_print_info.cold.1+0x20/0x20 [ 41.333544] panic+0x2ad/0x55c [ 41.336727] ? add_taint.cold.5+0x16/0x16 [ 41.340861] ? preempt_schedule+0x4d/0x60 [ 41.344993] ? ___preempt_schedule+0x16/0x18 [ 41.349403] ? trace_hardirqs_on+0xb4/0x310 [ 41.353740] kasan_end_report+0x47/0x4f [ 41.357701] kasan_report.cold.8+0x76/0x309 [ 41.362022] ? tipc_group_bc_cong+0x327/0x3f0 [ 41.366520] __asan_report_load2_noabort+0x14/0x20 [ 41.371436] tipc_group_bc_cong+0x327/0x3f0 [ 41.375742] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 41.380834] ? tipc_group_cong+0x5d0/0x5d0 [ 41.385055] ? remove_wait_queue+0x1a6/0x360 [ 41.389451] ? add_wait_queue+0x2b0/0x2b0 [ 41.393583] ? __local_bh_enable_ip+0x160/0x260 [ 41.398239] tipc_send_group_bcast+0x50a/0xd90 [ 41.402808] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 41.407817] ? __init_waitqueue_head+0x150/0x150 [ 41.412582] ? mark_held_locks+0x130/0x130 [ 41.416800] ? __might_sleep+0x95/0x190 [ 41.420773] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.426325] ? futex_wait_queue_me+0x55d/0x840 [ 41.430898] ? refill_pi_state_cache.part.8+0x310/0x310 [ 41.436247] ? print_usage_bug+0xc0/0xc0 [ 41.440292] __tipc_sendmsg+0xeec/0x1d40 [ 41.444366] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.449888] ? get_futex_value_locked+0xcb/0xf0 [ 41.454544] ? tipc_sendmcast+0xf50/0xf50 [ 41.458675] ? futex_wake+0x760/0x760 [ 41.462463] ? __lock_acquire+0x62f/0x4c20 [ 41.466696] ? zap_class+0x640/0x640 [ 41.470395] ? print_usage_bug+0xc0/0xc0 [ 41.474460] ? find_held_lock+0x36/0x1c0 [ 41.478507] ? mark_held_locks+0xc7/0x130 [ 41.482640] ? __local_bh_enable_ip+0x160/0x260 [ 41.487315] ? __local_bh_enable_ip+0x160/0x260 [ 41.491985] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 41.496552] ? trace_hardirqs_on+0xbd/0x310 [ 41.500860] ? lock_release+0xa00/0xa00 [ 41.504818] ? lock_sock_nested+0xe2/0x120 [ 41.509040] ? trace_hardirqs_off_caller+0x310/0x310 [ 41.514149] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.519698] ? check_preemption_disabled+0x48/0x280 [ 41.524700] ? lock_sock_nested+0x9a/0x120 [ 41.528935] ? lock_sock_nested+0x9a/0x120 [ 41.533171] ? __local_bh_enable_ip+0x160/0x260 [ 41.537824] tipc_sendmsg+0x50/0x70 [ 41.541442] ? __tipc_sendmsg+0x1d40/0x1d40 [ 41.545755] sock_sendmsg+0xd5/0x120 [ 41.549455] ___sys_sendmsg+0x51d/0x930 [ 41.553416] ? zap_class+0x640/0x640 [ 41.557118] ? copy_msghdr_from_user+0x580/0x580 [ 41.561860] ? find_held_lock+0x36/0x1c0 [ 41.565905] ? __fget_light+0x2e9/0x430 [ 41.569876] ? fget_raw+0x20/0x20 [ 41.573324] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 41.577911] ? trace_hardirqs_on+0xbd/0x310 [ 41.582244] ? _raw_spin_unlock_bh+0x30/0x40 [ 41.586636] ? trace_hardirqs_off_caller+0x310/0x310 [ 41.591724] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.597248] ? check_preemption_disabled+0x48/0x280 [ 41.602247] ? release_sock+0x1ec/0x2c0 [ 41.606204] ? release_sock+0x1ec/0x2c0 [ 41.610163] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.615684] ? sockfd_lookup_light+0xc5/0x160 [ 41.620166] __sys_sendmmsg+0x246/0x6d0 [ 41.624125] ? __ia32_sys_sendmsg+0xb0/0xb0 [ 41.628430] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.633952] ? rcvbuf_limit+0x2c0/0x2c0 [ 41.637913] ? aa_sock_opt_perm.isra.13+0xa1/0x130 [ 41.642842] ? __x64_sys_futex+0x47f/0x6a0 [ 41.647069] ? do_syscall_64+0x9a/0x820 [ 41.651027] ? do_syscall_64+0x9a/0x820 [ 41.654985] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 41.659561] ? trace_hardirqs_on+0xbd/0x310 [ 41.663872] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 41.669270] ? trace_hardirqs_off_caller+0x310/0x310 [ 41.674360] __x64_sys_sendmmsg+0x9d/0x100 [ 41.678607] do_syscall_64+0x1b9/0x820 [ 41.682495] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 41.687848] ? syscall_return_slowpath+0x5e0/0x5e0 [ 41.692761] ? trace_hardirqs_on_caller+0x310/0x310 [ 41.697760] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 41.702783] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 41.709475] ? __switch_to_asm+0x40/0x70 [ 41.713531] ? __switch_to_asm+0x34/0x70 [ 41.717589] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.722434] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 41.727605] RIP: 0033:0x446339 [ 41.730779] 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 [ 41.749680] RSP: 002b:00007f15687d7db8 EFLAGS: 00000297 ORIG_RAX: 0000000000000133 [ 41.757387] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446339 [ 41.764641] RDX: 0000000000000142 RSI: 0000000020000000 RDI: 0000000000000006 [ 41.771894] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 41.779163] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 41.786430] R13: 00007ffe412e39af R14: 00007f15687d89c0 R15: 00000000006dad2c [ 41.794663] Kernel Offset: disabled [ 41.798286] Rebooting in 86400 seconds..