[....] 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. [ 28.186499] kauditd_printk_skb: 7 callbacks suppressed [ 28.186511] audit: type=1800 audit(1544582048.726:29): pid=5843 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 [ 28.220911] audit: type=1800 audit(1544582048.726:30): pid=5843 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 '10.128.10.1' (ECDSA) to the list of known hosts. executing program executing program executing program syzkaller login: [ 47.741999] ================================================================== [ 47.749573] BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 [ 47.756401] Read of size 2 at addr ffff8881d784ce74 by task syz-executor854/6012 [ 47.763964] [ 47.765599] CPU: 0 PID: 6012 Comm: syz-executor854 Not tainted 4.20.0-rc6+ #371 [ 47.773030] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.782443] Call Trace: [ 47.785031] dump_stack+0x244/0x39d [ 47.788648] ? dump_stack_print_info.cold.1+0x20/0x20 [ 47.793827] ? printk+0xa7/0xcf [ 47.797105] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 47.801857] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 47.806958] print_address_description.cold.7+0x9/0x1ff [ 47.812316] kasan_report.cold.8+0x242/0x309 [ 47.816712] ? tipc_group_bc_cong+0x327/0x3f0 [ 47.821193] __asan_report_load2_noabort+0x14/0x20 [ 47.826117] tipc_group_bc_cong+0x327/0x3f0 [ 47.830441] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 47.835548] ? tipc_group_cong+0x5d0/0x5d0 [ 47.839768] ? remove_wait_queue+0x1a6/0x360 [ 47.844164] ? add_wait_queue+0x2b0/0x2b0 [ 47.848308] ? __local_bh_enable_ip+0x160/0x260 [ 47.852985] tipc_send_group_bcast+0x50a/0xd90 [ 47.857561] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 47.862569] ? __init_waitqueue_head+0x150/0x150 [ 47.867321] ? refill_pi_state_cache.part.8+0x310/0x310 [ 47.872690] ? mark_held_locks+0x130/0x130 [ 47.876915] ? futex_wait_setup+0x266/0x3e0 [ 47.881230] ? futex_wake+0x760/0x760 [ 47.885018] ? print_usage_bug+0xc0/0xc0 [ 47.889070] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 47.894249] __tipc_sendmsg+0xeec/0x1d40 [ 47.898344] ? futex_wait+0x5ec/0xa50 [ 47.902152] ? tipc_sendmcast+0xf50/0xf50 [ 47.906288] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 47.911659] ? zap_class+0x640/0x640 [ 47.915405] ? print_usage_bug+0xc0/0xc0 [ 47.919466] ? find_held_lock+0x36/0x1c0 [ 47.923514] ? mark_held_locks+0xc7/0x130 [ 47.927687] ? __local_bh_enable_ip+0x160/0x260 [ 47.932343] ? __local_bh_enable_ip+0x160/0x260 [ 47.937002] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 47.941573] ? trace_hardirqs_on+0xbd/0x310 [ 47.945885] ? lock_release+0xa00/0xa00 [ 47.949845] ? lock_sock_nested+0xe2/0x120 [ 47.954064] ? trace_hardirqs_off_caller+0x310/0x310 [ 47.959152] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 47.964681] ? check_preemption_disabled+0x48/0x280 [ 47.969689] ? lock_sock_nested+0x9a/0x120 [ 47.973912] ? lock_sock_nested+0x9a/0x120 [ 47.978138] ? __local_bh_enable_ip+0x160/0x260 [ 47.982801] tipc_sendmsg+0x50/0x70 [ 47.986455] ? __tipc_sendmsg+0x1d40/0x1d40 [ 47.990769] sock_sendmsg+0xd5/0x120 [ 47.994467] ___sys_sendmsg+0x7fd/0x930 [ 47.998608] ? find_held_lock+0x36/0x1c0 [ 48.002655] ? copy_msghdr_from_user+0x580/0x580 [ 48.007395] ? __fd_install+0x2b5/0x8f0 [ 48.011353] ? check_preemption_disabled+0x48/0x280 [ 48.016360] ? __fget_light+0x2e9/0x430 [ 48.020318] ? fget_raw+0x20/0x20 [ 48.023757] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.029274] ? __fd_install+0x2f9/0x8f0 [ 48.033230] ? get_unused_fd_flags+0x1a0/0x1a0 [ 48.037797] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 48.043317] ? sockfd_lookup_light+0xc5/0x160 [ 48.047798] __sys_sendmsg+0x11d/0x280 [ 48.051670] ? __ia32_sys_shutdown+0x80/0x80 [ 48.056061] ? fput+0x130/0x1a0 [ 48.059329] ? __x64_sys_futex+0x47f/0x6a0 [ 48.063548] ? do_syscall_64+0x9a/0x820 [ 48.067593] ? do_syscall_64+0x9a/0x820 [ 48.071567] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.076657] __x64_sys_sendmsg+0x78/0xb0 [ 48.080748] do_syscall_64+0x1b9/0x820 [ 48.084628] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 48.089974] ? syscall_return_slowpath+0x5e0/0x5e0 [ 48.094888] ? trace_hardirqs_on_caller+0x310/0x310 [ 48.099893] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 48.104897] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 48.111545] ? __switch_to_asm+0x40/0x70 [ 48.115588] ? __switch_to_asm+0x34/0x70 [ 48.119637] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 48.124467] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.129636] RIP: 0033:0x446389 [ 48.132812] 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 [ 48.151692] RSP: 002b:00007f2a41358db8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 48.159382] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 48.166630] RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000005 [ 48.173878] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 48.181129] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 48.188443] R13: 00007fffe74ab79f R14: 00007f2a413599c0 R15: 00000000006dad2c [ 48.195710] [ 48.197381] Allocated by task 6013: [ 48.201023] save_stack+0x43/0xd0 [ 48.204483] kasan_kmalloc+0xc7/0xe0 [ 48.208178] kmem_cache_alloc_trace+0x152/0x750 [ 48.212828] tipc_group_create+0x152/0xa70 [ 48.217041] tipc_setsockopt+0x2d1/0xd70 [ 48.221083] __sys_setsockopt+0x1ba/0x3c0 [ 48.225214] __x64_sys_setsockopt+0xbe/0x150 [ 48.229603] do_syscall_64+0x1b9/0x820 [ 48.233578] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.238749] [ 48.240360] Freed by task 6013: [ 48.243625] save_stack+0x43/0xd0 [ 48.247059] __kasan_slab_free+0x102/0x150 [ 48.251275] kasan_slab_free+0xe/0x10 [ 48.255056] kfree+0xcf/0x230 [ 48.258143] tipc_group_delete+0x2e4/0x3f0 [ 48.262357] tipc_sk_leave+0x113/0x220 [ 48.266223] tipc_setsockopt+0x97d/0xd70 [ 48.270265] __sys_setsockopt+0x1ba/0x3c0 [ 48.274393] __x64_sys_setsockopt+0xbe/0x150 [ 48.278782] do_syscall_64+0x1b9/0x820 [ 48.282652] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.287819] [ 48.289472] The buggy address belongs to the object at ffff8881d784ce00 [ 48.289472] which belongs to the cache kmalloc-192 of size 192 [ 48.302120] The buggy address is located 116 bytes inside of [ 48.302120] 192-byte region [ffff8881d784ce00, ffff8881d784cec0) [ 48.314016] The buggy address belongs to the page: [ 48.318934] page:ffffea00075e1300 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 [ 48.327065] flags: 0x2fffc0000000200(slab) [ 48.331283] raw: 02fffc0000000200 ffffea00075f5148 ffff8881da801148 ffff8881da800040 [ 48.339156] raw: 0000000000000000 ffff8881d784c000 0000000100000010 0000000000000000 [ 48.347011] page dumped because: kasan: bad access detected [ 48.352713] [ 48.354316] Memory state around the buggy address: [ 48.359224] ffff8881d784cd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 48.366668] ffff8881d784cd80: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 48.374012] >ffff8881d784ce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.381354] ^ [ 48.388350] ffff8881d784ce80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 48.395688] ffff8881d784cf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.403023] ================================================================== [ 48.410361] Disabling lock debugging due to kernel taint [ 48.416008] Kernel panic - not syncing: panic_on_warn set ... [ 48.421889] CPU: 0 PID: 6012 Comm: syz-executor854 Tainted: G B 4.20.0-rc6+ #371 [ 48.430702] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.440036] Call Trace: [ 48.442606] dump_stack+0x244/0x39d [ 48.446217] ? dump_stack_print_info.cold.1+0x20/0x20 [ 48.451390] panic+0x2ad/0x55c [ 48.454621] ? add_taint.cold.5+0x16/0x16 [ 48.458756] ? preempt_schedule+0x4d/0x60 [ 48.462886] ? ___preempt_schedule+0x16/0x18 [ 48.467285] ? trace_hardirqs_on+0xb4/0x310 [ 48.471593] kasan_end_report+0x47/0x4f [ 48.475556] kasan_report.cold.8+0x76/0x309 [ 48.479862] ? tipc_group_bc_cong+0x327/0x3f0 [ 48.484353] __asan_report_load2_noabort+0x14/0x20 [ 48.489271] tipc_group_bc_cong+0x327/0x3f0 [ 48.493577] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 48.498673] ? tipc_group_cong+0x5d0/0x5d0 [ 48.502888] ? remove_wait_queue+0x1a6/0x360 [ 48.507276] ? add_wait_queue+0x2b0/0x2b0 [ 48.511404] ? __local_bh_enable_ip+0x160/0x260 [ 48.516060] tipc_send_group_bcast+0x50a/0xd90 [ 48.520633] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 48.525638] ? __init_waitqueue_head+0x150/0x150 [ 48.530376] ? refill_pi_state_cache.part.8+0x310/0x310 [ 48.535767] ? mark_held_locks+0x130/0x130 [ 48.539989] ? futex_wait_setup+0x266/0x3e0 [ 48.544298] ? futex_wake+0x760/0x760 [ 48.548086] ? print_usage_bug+0xc0/0xc0 [ 48.552135] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 48.557306] __tipc_sendmsg+0xeec/0x1d40 [ 48.561355] ? futex_wait+0x5ec/0xa50 [ 48.565142] ? tipc_sendmcast+0xf50/0xf50 [ 48.569275] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 48.574515] ? zap_class+0x640/0x640 [ 48.578220] ? print_usage_bug+0xc0/0xc0 [ 48.582265] ? find_held_lock+0x36/0x1c0 [ 48.586319] ? mark_held_locks+0xc7/0x130 [ 48.590457] ? __local_bh_enable_ip+0x160/0x260 [ 48.595110] ? __local_bh_enable_ip+0x160/0x260 [ 48.599760] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 48.604324] ? trace_hardirqs_on+0xbd/0x310 [ 48.608623] ? lock_release+0xa00/0xa00 [ 48.612583] ? lock_sock_nested+0xe2/0x120 [ 48.616797] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.621881] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.627402] ? check_preemption_disabled+0x48/0x280 [ 48.632408] ? lock_sock_nested+0x9a/0x120 [ 48.636633] ? lock_sock_nested+0x9a/0x120 [ 48.640848] ? __local_bh_enable_ip+0x160/0x260 [ 48.645498] tipc_sendmsg+0x50/0x70 [ 48.649107] ? __tipc_sendmsg+0x1d40/0x1d40 [ 48.653447] sock_sendmsg+0xd5/0x120 [ 48.657149] ___sys_sendmsg+0x7fd/0x930 [ 48.661110] ? find_held_lock+0x36/0x1c0 [ 48.665153] ? copy_msghdr_from_user+0x580/0x580 [ 48.669894] ? __fd_install+0x2b5/0x8f0 [ 48.673864] ? check_preemption_disabled+0x48/0x280 [ 48.678864] ? __fget_light+0x2e9/0x430 [ 48.682820] ? fget_raw+0x20/0x20 [ 48.686299] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 48.691823] ? __fd_install+0x2f9/0x8f0 [ 48.695777] ? get_unused_fd_flags+0x1a0/0x1a0 [ 48.700345] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 48.705860] ? sockfd_lookup_light+0xc5/0x160 [ 48.710338] __sys_sendmsg+0x11d/0x280 [ 48.714213] ? __ia32_sys_shutdown+0x80/0x80 [ 48.718608] ? fput+0x130/0x1a0 [ 48.721873] ? __x64_sys_futex+0x47f/0x6a0 [ 48.726092] ? do_syscall_64+0x9a/0x820 [ 48.730053] ? do_syscall_64+0x9a/0x820 [ 48.734011] ? trace_hardirqs_off_caller+0x310/0x310 [ 48.739097] __x64_sys_sendmsg+0x78/0xb0 [ 48.743145] do_syscall_64+0x1b9/0x820 [ 48.747019] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 48.752371] ? syscall_return_slowpath+0x5e0/0x5e0 [ 48.757287] ? trace_hardirqs_on_caller+0x310/0x310 [ 48.762286] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 48.767344] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 48.773997] ? __switch_to_asm+0x40/0x70 [ 48.778037] ? __switch_to_asm+0x34/0x70 [ 48.782086] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 48.786910] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 48.792084] RIP: 0033:0x446389 [ 48.795261] 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 [ 48.814146] RSP: 002b:00007f2a41358db8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 48.821839] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 48.829097] RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000005 [ 48.836354] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 48.843678] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 48.850954] R13: 00007fffe74ab79f R14: 00007f2a413599c0 R15: 00000000006dad2c [ 48.859149] Kernel Offset: disabled [ 48.862788] Rebooting in 86400 seconds..