[....] 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. [ 28.310318] kauditd_printk_skb: 8 callbacks suppressed [ 28.310330] audit: type=1800 audit(1544975720.607:29): pid=5876 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 [ 28.362166] audit: type=1800 audit(1544975720.607:30): pid=5876 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 Warning: Permanently added '10.128.10.34' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 47.733589] ================================================================== [ 47.741175] BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 [ 47.748009] Read of size 2 at addr ffff8881d1ee4474 by task syz-executor233/6035 [ 47.755521] [ 47.757138] CPU: 0 PID: 6035 Comm: syz-executor233 Not tainted 4.20.0-rc6+ #347 [ 47.764577] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.773919] Call Trace: [ 47.776496] dump_stack+0x244/0x39d [ 47.780128] ? dump_stack_print_info.cold.1+0x20/0x20 [ 47.785318] ? printk+0xa7/0xcf [ 47.788586] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 47.793328] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 47.798425] print_address_description.cold.7+0x9/0x1ff [ 47.803776] kasan_report.cold.8+0x242/0x309 [ 47.808171] ? tipc_group_bc_cong+0x327/0x3f0 [ 47.812654] __asan_report_load2_noabort+0x14/0x20 [ 47.817570] tipc_group_bc_cong+0x327/0x3f0 [ 47.821978] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 47.827079] ? tipc_group_cong+0x5d0/0x5d0 [ 47.831332] ? remove_wait_queue+0x1a6/0x360 [ 47.835730] ? add_wait_queue+0x2b0/0x2b0 [ 47.839871] ? __local_bh_enable_ip+0x160/0x260 [ 47.844530] tipc_send_group_bcast+0x50a/0xd90 [ 47.849141] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 47.854151] ? __init_waitqueue_head+0x150/0x150 [ 47.858896] ? refill_pi_state_cache.part.8+0x310/0x310 [ 47.864259] ? mark_held_locks+0x130/0x130 [ 47.868480] ? futex_wait_setup+0x266/0x3e0 [ 47.872803] ? futex_wake+0x760/0x760 [ 47.876605] ? print_usage_bug+0xc0/0xc0 [ 47.880653] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 47.885835] __tipc_sendmsg+0xeec/0x1d40 [ 47.889884] ? futex_wait+0x5ec/0xa50 [ 47.893675] ? tipc_sendmcast+0xf50/0xf50 [ 47.897809] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 47.902985] ? zap_class+0x640/0x640 [ 47.906688] ? print_usage_bug+0xc0/0xc0 [ 47.910743] ? find_held_lock+0x36/0x1c0 [ 47.914797] ? mark_held_locks+0xc7/0x130 [ 47.918933] ? __local_bh_enable_ip+0x160/0x260 [ 47.923590] ? __local_bh_enable_ip+0x160/0x260 [ 47.928252] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 47.932832] ? trace_hardirqs_on+0xbd/0x310 [ 47.937145] ? lock_release+0xa00/0xa00 [ 47.941115] ? lock_sock_nested+0xe2/0x120 [ 47.945336] ? trace_hardirqs_off_caller+0x310/0x310 [ 47.950425] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 47.955952] ? check_preemption_disabled+0x48/0x280 [ 47.960954] ? lock_sock_nested+0x9a/0x120 [ 47.965193] ? lock_sock_nested+0x9a/0x120 [ 47.969425] ? __local_bh_enable_ip+0x160/0x260 [ 47.974115] tipc_sendmsg+0x50/0x70 [ 47.977732] ? __tipc_sendmsg+0x1d40/0x1d40 [ 47.982048] sock_sendmsg+0xd5/0x120 [ 47.985754] ___sys_sendmsg+0x7fd/0x930 [ 47.989716] ? find_held_lock+0x36/0x1c0 [ 47.993766] ? copy_msghdr_from_user+0x580/0x580 [ 47.998508] ? __fd_install+0x2b5/0x8f0 [ 48.002473] ? check_preemption_disabled+0x48/0x280 [ 48.007477] ? __fget_light+0x2e9/0x430 [ 48.011440] ? fget_raw+0x20/0x20 [ 48.014883] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.020407] ? __fd_install+0x2f9/0x8f0 [ 48.024384] ? get_unused_fd_flags+0x1a0/0x1a0 [ 48.028968] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 48.034522] ? sockfd_lookup_light+0xc5/0x160 [ 48.039005] __sys_sendmsg+0x11d/0x280 [ 48.042883] ? __ia32_sys_shutdown+0x80/0x80 [ 48.047282] ? __x64_sys_futex+0x47f/0x6a0 [ 48.051523] ? do_syscall_64+0x9a/0x820 [ 48.055484] ? do_syscall_64+0x9a/0x820 [ 48.059460] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.064556] __x64_sys_sendmsg+0x78/0xb0 [ 48.068604] do_syscall_64+0x1b9/0x820 [ 48.072481] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 48.077844] ? syscall_return_slowpath+0x5e0/0x5e0 [ 48.082771] ? trace_hardirqs_on_caller+0x310/0x310 [ 48.087920] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 48.092938] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 48.099604] ? __switch_to_asm+0x40/0x70 [ 48.103650] ? __switch_to_asm+0x34/0x70 [ 48.107704] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 48.112554] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.117730] RIP: 0033:0x446389 [ 48.120909] 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 [ 48.139963] RSP: 002b:00007fad910a6db8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 48.147658] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 48.154926] RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000005 [ 48.162200] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 48.169461] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 48.176715] R13: 00007ffc0c2d003f R14: 00007fad910a79c0 R15: 00000000006dad2c [ 48.184003] [ 48.185619] Allocated by task 6036: [ 48.189266] save_stack+0x43/0xd0 [ 48.192722] kasan_kmalloc+0xc7/0xe0 [ 48.196421] kmem_cache_alloc_trace+0x152/0x750 [ 48.201075] tipc_group_create+0x152/0xa70 [ 48.205301] tipc_setsockopt+0x2d1/0xd70 [ 48.209346] __sys_setsockopt+0x1ba/0x3c0 [ 48.213490] __x64_sys_setsockopt+0xbe/0x150 [ 48.217884] do_syscall_64+0x1b9/0x820 [ 48.221762] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.226955] [ 48.228568] Freed by task 6036: [ 48.231842] save_stack+0x43/0xd0 [ 48.235290] __kasan_slab_free+0x102/0x150 [ 48.239510] kasan_slab_free+0xe/0x10 [ 48.243307] kfree+0xcf/0x230 [ 48.246397] tipc_group_delete+0x2e4/0x3f0 [ 48.250619] tipc_sk_leave+0x113/0x220 [ 48.254489] tipc_setsockopt+0x97d/0xd70 [ 48.258545] __sys_setsockopt+0x1ba/0x3c0 [ 48.262801] __x64_sys_setsockopt+0xbe/0x150 [ 48.267197] do_syscall_64+0x1b9/0x820 [ 48.271070] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.276249] [ 48.277861] The buggy address belongs to the object at ffff8881d1ee4400 [ 48.277861] which belongs to the cache kmalloc-192 of size 192 [ 48.290500] The buggy address is located 116 bytes inside of [ 48.290500] 192-byte region [ffff8881d1ee4400, ffff8881d1ee44c0) [ 48.302352] The buggy address belongs to the page: [ 48.307269] page:ffffea000747b900 count:1 mapcount:0 mapping:ffff8881da800040 index:0xffff8881d1ee4000 [ 48.316695] flags: 0x2fffc0000000200(slab) [ 48.320919] raw: 02fffc0000000200 ffffea0007669908 ffff8881da801138 ffff8881da800040 [ 48.328799] raw: ffff8881d1ee4000 ffff8881d1ee4000 000000010000000d 0000000000000000 [ 48.336674] page dumped because: kasan: bad access detected [ 48.342365] [ 48.343976] Memory state around the buggy address: [ 48.349472] ffff8881d1ee4300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.356952] ffff8881d1ee4380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 48.364303] >ffff8881d1ee4400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.371756] ^ [ 48.378757] ffff8881d1ee4480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 48.386125] ffff8881d1ee4500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 48.393481] ================================================================== [ 48.400830] Disabling lock debugging due to kernel taint [ 48.406637] Kernel panic - not syncing: panic_on_warn set ... [ 48.412524] CPU: 0 PID: 6035 Comm: syz-executor233 Tainted: G B 4.20.0-rc6+ #347 [ 48.421451] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.430788] Call Trace: [ 48.433370] dump_stack+0x244/0x39d [ 48.436985] ? dump_stack_print_info.cold.1+0x20/0x20 [ 48.442276] panic+0x2ad/0x55c [ 48.445456] ? add_taint.cold.5+0x16/0x16 [ 48.449599] ? preempt_schedule+0x4d/0x60 [ 48.453731] ? ___preempt_schedule+0x16/0x18 [ 48.458124] ? trace_hardirqs_on+0xb4/0x310 [ 48.462431] kasan_end_report+0x47/0x4f [ 48.466570] kasan_report.cold.8+0x76/0x309 [ 48.470880] ? tipc_group_bc_cong+0x327/0x3f0 [ 48.475361] __asan_report_load2_noabort+0x14/0x20 [ 48.480285] tipc_group_bc_cong+0x327/0x3f0 [ 48.484748] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 48.489946] ? tipc_group_cong+0x5d0/0x5d0 [ 48.494168] ? remove_wait_queue+0x1a6/0x360 [ 48.498562] ? add_wait_queue+0x2b0/0x2b0 [ 48.502694] ? __local_bh_enable_ip+0x160/0x260 [ 48.507351] tipc_send_group_bcast+0x50a/0xd90 [ 48.511938] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 48.516956] ? __init_waitqueue_head+0x150/0x150 [ 48.521692] ? refill_pi_state_cache.part.8+0x310/0x310 [ 48.527043] ? mark_held_locks+0x130/0x130 [ 48.531268] ? futex_wait_setup+0x266/0x3e0 [ 48.535589] ? futex_wake+0x760/0x760 [ 48.539527] ? print_usage_bug+0xc0/0xc0 [ 48.543588] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 48.548782] __tipc_sendmsg+0xeec/0x1d40 [ 48.552825] ? futex_wait+0x5ec/0xa50 [ 48.556610] ? tipc_sendmcast+0xf50/0xf50 [ 48.560742] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 48.565921] ? zap_class+0x640/0x640 [ 48.569789] ? print_usage_bug+0xc0/0xc0 [ 48.573853] ? find_held_lock+0x36/0x1c0 [ 48.577897] ? mark_held_locks+0xc7/0x130 [ 48.582027] ? __local_bh_enable_ip+0x160/0x260 [ 48.586679] ? __local_bh_enable_ip+0x160/0x260 [ 48.591331] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 48.595909] ? trace_hardirqs_on+0xbd/0x310 [ 48.600399] ? lock_release+0xa00/0xa00 [ 48.604357] ? lock_sock_nested+0xe2/0x120 [ 48.609298] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.614395] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.619923] ? check_preemption_disabled+0x48/0x280 [ 48.624925] ? lock_sock_nested+0x9a/0x120 [ 48.629139] ? lock_sock_nested+0x9a/0x120 [ 48.633476] ? __local_bh_enable_ip+0x160/0x260 [ 48.638137] tipc_sendmsg+0x50/0x70 [ 48.641818] ? __tipc_sendmsg+0x1d40/0x1d40 [ 48.646134] sock_sendmsg+0xd5/0x120 [ 48.649835] ___sys_sendmsg+0x7fd/0x930 [ 48.653797] ? find_held_lock+0x36/0x1c0 [ 48.658192] ? copy_msghdr_from_user+0x580/0x580 [ 48.662932] ? __fd_install+0x2b5/0x8f0 [ 48.666893] ? check_preemption_disabled+0x48/0x280 [ 48.671899] ? __fget_light+0x2e9/0x430 [ 48.675855] ? fget_raw+0x20/0x20 [ 48.679296] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.684818] ? __fd_install+0x2f9/0x8f0 [ 48.688775] ? get_unused_fd_flags+0x1a0/0x1a0 [ 48.693355] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 48.698891] ? sockfd_lookup_light+0xc5/0x160 [ 48.703381] __sys_sendmsg+0x11d/0x280 [ 48.707252] ? __ia32_sys_shutdown+0x80/0x80 [ 48.711645] ? __x64_sys_futex+0x47f/0x6a0 [ 48.715879] ? do_syscall_64+0x9a/0x820 [ 48.719834] ? do_syscall_64+0x9a/0x820 [ 48.723794] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.728887] __x64_sys_sendmsg+0x78/0xb0 [ 48.732933] do_syscall_64+0x1b9/0x820 [ 48.736910] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 48.742262] ? syscall_return_slowpath+0x5e0/0x5e0 [ 48.747183] ? trace_hardirqs_on_caller+0x310/0x310 [ 48.752186] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 48.757189] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 48.763846] ? __switch_to_asm+0x40/0x70 [ 48.767888] ? __switch_to_asm+0x34/0x70 [ 48.771933] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 48.776759] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.781929] RIP: 0033:0x446389 [ 48.785243] 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 [ 48.804278] RSP: 002b:00007fad910a6db8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 48.811976] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 48.819229] RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000005 [ 48.826481] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 48.833733] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 48.840992] R13: 00007ffc0c2d003f R14: 00007fad910a79c0 R15: 00000000006dad2c [ 48.849259] Kernel Offset: disabled [ 48.852890] Rebooting in 86400 seconds..