[....] 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. [ 28.713215] kauditd_printk_skb: 8 callbacks suppressed [ 28.713227] audit: type=1800 audit(1544599464.021:29): pid=5871 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 [ 28.739672] audit: type=1800 audit(1544599464.031:30): pid=5871 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: [ 32.510486] sshd (6010) used greatest stack depth: 15744 bytes left Warning: Permanently added '10.128.0.140' (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 [ 51.013975] ================================================================== [ 51.021557] BUG: KASAN: use-after-free in tipc_group_bc_cong+0x327/0x3f0 [ 51.028390] Read of size 2 at addr ffff8881d80bec74 by task syz-executor642/6088 [ 51.036182] [ 51.037933] CPU: 0 PID: 6088 Comm: syz-executor642 Not tainted 4.20.0-rc6+ #339 [ 51.045383] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.054835] Call Trace: [ 51.057422] dump_stack+0x244/0x39d [ 51.061085] ? dump_stack_print_info.cold.1+0x20/0x20 [ 51.066369] ? printk+0xa7/0xcf [ 51.069656] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 51.074510] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 51.079703] print_address_description.cold.7+0x9/0x1ff [ 51.085062] kasan_report.cold.8+0x242/0x309 [ 51.089550] ? tipc_group_bc_cong+0x327/0x3f0 [ 51.094099] __asan_report_load2_noabort+0x14/0x20 [ 51.099132] tipc_group_bc_cong+0x327/0x3f0 [ 51.103500] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 51.108658] ? tipc_group_cong+0x5d0/0x5d0 [ 51.113103] ? remove_wait_queue+0x1a6/0x360 [ 51.117509] ? add_wait_queue+0x2b0/0x2b0 [ 51.121640] ? __local_bh_enable_ip+0x160/0x260 [ 51.126298] tipc_send_group_bcast+0x50a/0xd90 [ 51.130872] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 51.135891] ? __init_waitqueue_head+0x150/0x150 [ 51.140630] ? refill_pi_state_cache.part.8+0x310/0x310 [ 51.146150] ? mark_held_locks+0x130/0x130 [ 51.150380] ? futex_wait_setup+0x266/0x3e0 [ 51.154690] ? futex_wake+0x760/0x760 [ 51.158521] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 51.163744] __tipc_sendmsg+0xeec/0x1d40 [ 51.167801] ? futex_wait+0x5ec/0xa50 [ 51.171598] ? tipc_sendmcast+0xf50/0xf50 [ 51.175736] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 51.180911] ? zap_class+0x640/0x640 [ 51.184619] ? print_usage_bug+0xc0/0xc0 [ 51.188675] ? find_held_lock+0x36/0x1c0 [ 51.192726] ? mark_held_locks+0xc7/0x130 [ 51.196861] ? __local_bh_enable_ip+0x160/0x260 [ 51.201537] ? __local_bh_enable_ip+0x160/0x260 [ 51.206208] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 51.210779] ? trace_hardirqs_on+0xbd/0x310 [ 51.215093] ? lock_release+0xa00/0xa00 [ 51.219051] ? lock_sock_nested+0xe2/0x120 [ 51.223271] ? trace_hardirqs_off_caller+0x310/0x310 [ 51.228363] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.233929] ? check_preemption_disabled+0x48/0x280 [ 51.239038] ? lock_sock_nested+0x9a/0x120 [ 51.243271] ? lock_sock_nested+0x9a/0x120 [ 51.247504] ? __local_bh_enable_ip+0x160/0x260 [ 51.252197] tipc_sendmsg+0x50/0x70 [ 51.255836] ? __tipc_sendmsg+0x1d40/0x1d40 [ 51.260181] sock_sendmsg+0xd5/0x120 [ 51.263892] ___sys_sendmsg+0x7fd/0x930 [ 51.267865] ? __local_bh_enable_ip+0x160/0x260 [ 51.272537] ? copy_msghdr_from_user+0x580/0x580 [ 51.277281] ? _raw_spin_unlock_bh+0x30/0x40 [ 51.281692] ? trace_hardirqs_off_caller+0x310/0x310 [ 51.286784] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.292308] ? check_preemption_disabled+0x48/0x280 [ 51.297367] ? release_sock+0x1ec/0x2c0 [ 51.301347] ? __fget_light+0x2e9/0x430 [ 51.305326] ? fget_raw+0x20/0x20 [ 51.308788] ? release_sock+0x1ec/0x2c0 [ 51.312748] ? __release_sock+0x3a0/0x3a0 [ 51.316881] ? tipc_nametbl_build_group+0x273/0x360 [ 51.321887] ? tipc_setsockopt+0x726/0xd70 [ 51.326112] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 51.331647] ? sockfd_lookup_light+0xc5/0x160 [ 51.336180] __sys_sendmsg+0x11d/0x280 [ 51.340063] ? __ia32_sys_shutdown+0x80/0x80 [ 51.344458] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 51.349982] ? fput+0x130/0x1a0 [ 51.353256] ? __x64_sys_futex+0x47f/0x6a0 [ 51.357483] ? do_syscall_64+0x9a/0x820 [ 51.361486] ? do_syscall_64+0x9a/0x820 [ 51.365458] ? trace_hardirqs_off_caller+0x310/0x310 [ 51.370552] __x64_sys_sendmsg+0x78/0xb0 [ 51.374606] do_syscall_64+0x1b9/0x820 [ 51.378482] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 51.383833] ? syscall_return_slowpath+0x5e0/0x5e0 [ 51.388749] ? trace_hardirqs_on_caller+0x310/0x310 [ 51.393753] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 51.398754] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 51.405405] ? __switch_to_asm+0x40/0x70 [ 51.409448] ? __switch_to_asm+0x34/0x70 [ 51.413498] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 51.418339] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 51.423532] RIP: 0033:0x446389 [ 51.426713] 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 [ 51.445606] RSP: 002b:00007fadff57ddb8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 51.453315] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 51.460580] RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000005 [ 51.467836] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 51.475091] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 51.482365] R13: 00007ffc6c50142f R14: 00007fadff57e9c0 R15: 00000000006dad2c [ 51.489728] [ 51.491353] Allocated by task 6089: [ 51.494983] save_stack+0x43/0xd0 [ 51.498422] kasan_kmalloc+0xc7/0xe0 [ 51.502123] kmem_cache_alloc_trace+0x152/0x750 [ 51.506776] tipc_group_create+0x152/0xa70 [ 51.510993] tipc_setsockopt+0x2d1/0xd70 [ 51.515041] __sys_setsockopt+0x1ba/0x3c0 [ 51.519174] __x64_sys_setsockopt+0xbe/0x150 [ 51.523584] do_syscall_64+0x1b9/0x820 [ 51.527455] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 51.532620] [ 51.534229] Freed by task 6089: [ 51.537493] save_stack+0x43/0xd0 [ 51.540932] __kasan_slab_free+0x102/0x150 [ 51.545161] kasan_slab_free+0xe/0x10 [ 51.548962] kfree+0xcf/0x230 [ 51.552064] tipc_group_delete+0x2e4/0x3f0 [ 51.556284] tipc_sk_leave+0x113/0x220 [ 51.560165] tipc_setsockopt+0x97d/0xd70 [ 51.564224] __sys_setsockopt+0x1ba/0x3c0 [ 51.568362] __x64_sys_setsockopt+0xbe/0x150 [ 51.572755] do_syscall_64+0x1b9/0x820 [ 51.576630] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 51.581822] [ 51.583437] The buggy address belongs to the object at ffff8881d80bec00 [ 51.583437] which belongs to the cache kmalloc-192 of size 192 [ 51.596079] The buggy address is located 116 bytes inside of [ 51.596079] 192-byte region [ffff8881d80bec00, ffff8881d80becc0) [ 51.607934] The buggy address belongs to the page: [ 51.612846] page:ffffea0007602f80 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 [ 51.620984] flags: 0x2fffc0000000200(slab) [ 51.625205] raw: 02fffc0000000200 ffffea0007625748 ffffea0007600748 ffff8881da800040 [ 51.633084] raw: 0000000000000000 ffff8881d80be000 0000000100000010 0000000000000000 [ 51.640943] page dumped because: kasan: bad access detected [ 51.646632] [ 51.648241] Memory state around the buggy address: [ 51.653194] ffff8881d80beb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.660577] ffff8881d80beb80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 51.667925] >ffff8881d80bec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.675300] ^ [ 51.682310] ffff8881d80bec80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 51.689665] ffff8881d80bed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 51.697003] ================================================================== [ 51.704345] Disabling lock debugging due to kernel taint [ 51.710407] Kernel panic - not syncing: panic_on_warn set ... [ 51.716303] CPU: 0 PID: 6088 Comm: syz-executor642 Tainted: G B 4.20.0-rc6+ #339 [ 51.725128] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.734460] Call Trace: [ 51.737066] dump_stack+0x244/0x39d [ 51.740700] ? dump_stack_print_info.cold.1+0x20/0x20 [ 51.745877] panic+0x2ad/0x55c [ 51.749056] ? add_taint.cold.5+0x16/0x16 [ 51.753190] ? preempt_schedule+0x4d/0x60 [ 51.757492] ? ___preempt_schedule+0x16/0x18 [ 51.761890] ? trace_hardirqs_on+0xb4/0x310 [ 51.766200] kasan_end_report+0x47/0x4f [ 51.770160] kasan_report.cold.8+0x76/0x309 [ 51.774469] ? tipc_group_bc_cong+0x327/0x3f0 [ 51.778951] __asan_report_load2_noabort+0x14/0x20 [ 51.783985] tipc_group_bc_cong+0x327/0x3f0 [ 51.788294] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 51.793390] ? tipc_group_cong+0x5d0/0x5d0 [ 51.797628] ? remove_wait_queue+0x1a6/0x360 [ 51.802043] ? add_wait_queue+0x2b0/0x2b0 [ 51.806288] ? __local_bh_enable_ip+0x160/0x260 [ 51.810950] tipc_send_group_bcast+0x50a/0xd90 [ 51.815521] ? tipc_sk_sock_err.isra.61+0x2f0/0x2f0 [ 51.820524] ? __init_waitqueue_head+0x150/0x150 [ 51.825267] ? refill_pi_state_cache.part.8+0x310/0x310 [ 51.830620] ? mark_held_locks+0x130/0x130 [ 51.834840] ? futex_wait_setup+0x266/0x3e0 [ 51.839171] ? futex_wake+0x760/0x760 [ 51.842955] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 51.848133] __tipc_sendmsg+0xeec/0x1d40 [ 51.852193] ? futex_wait+0x5ec/0xa50 [ 51.856011] ? tipc_sendmcast+0xf50/0xf50 [ 51.860221] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 51.865401] ? zap_class+0x640/0x640 [ 51.869099] ? print_usage_bug+0xc0/0xc0 [ 51.873152] ? find_held_lock+0x36/0x1c0 [ 51.877212] ? mark_held_locks+0xc7/0x130 [ 51.881360] ? __local_bh_enable_ip+0x160/0x260 [ 51.886106] ? __local_bh_enable_ip+0x160/0x260 [ 51.890806] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 51.895376] ? trace_hardirqs_on+0xbd/0x310 [ 51.899681] ? lock_release+0xa00/0xa00 [ 51.903648] ? lock_sock_nested+0xe2/0x120 [ 51.907880] ? trace_hardirqs_off_caller+0x310/0x310 [ 51.912969] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.918494] ? check_preemption_disabled+0x48/0x280 [ 51.923501] ? lock_sock_nested+0x9a/0x120 [ 51.927724] ? lock_sock_nested+0x9a/0x120 [ 51.931942] ? __local_bh_enable_ip+0x160/0x260 [ 51.936601] tipc_sendmsg+0x50/0x70 [ 51.940213] ? __tipc_sendmsg+0x1d40/0x1d40 [ 51.944517] sock_sendmsg+0xd5/0x120 [ 51.948215] ___sys_sendmsg+0x7fd/0x930 [ 51.952171] ? __local_bh_enable_ip+0x160/0x260 [ 51.956826] ? copy_msghdr_from_user+0x580/0x580 [ 51.961606] ? _raw_spin_unlock_bh+0x30/0x40 [ 51.966022] ? trace_hardirqs_off_caller+0x310/0x310 [ 51.971111] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 51.976634] ? check_preemption_disabled+0x48/0x280 [ 51.981635] ? release_sock+0x1ec/0x2c0 [ 51.985710] ? __fget_light+0x2e9/0x430 [ 51.989676] ? fget_raw+0x20/0x20 [ 51.993114] ? release_sock+0x1ec/0x2c0 [ 51.997072] ? __release_sock+0x3a0/0x3a0 [ 52.001201] ? tipc_nametbl_build_group+0x273/0x360 [ 52.006201] ? tipc_setsockopt+0x726/0xd70 [ 52.010427] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 52.015986] ? sockfd_lookup_light+0xc5/0x160 [ 52.020464] __sys_sendmsg+0x11d/0x280 [ 52.024345] ? __ia32_sys_shutdown+0x80/0x80 [ 52.028745] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 52.034275] ? fput+0x130/0x1a0 [ 52.037540] ? __x64_sys_futex+0x47f/0x6a0 [ 52.041765] ? do_syscall_64+0x9a/0x820 [ 52.045729] ? do_syscall_64+0x9a/0x820 [ 52.049694] ? trace_hardirqs_off_caller+0x310/0x310 [ 52.054790] __x64_sys_sendmsg+0x78/0xb0 [ 52.058847] do_syscall_64+0x1b9/0x820 [ 52.062730] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 52.068081] ? syscall_return_slowpath+0x5e0/0x5e0 [ 52.073144] ? trace_hardirqs_on_caller+0x310/0x310 [ 52.078152] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 52.083162] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 52.089829] ? __switch_to_asm+0x40/0x70 [ 52.093873] ? __switch_to_asm+0x34/0x70 [ 52.097920] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 52.102747] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 52.107918] RIP: 0033:0x446389 [ 52.111096] 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 [ 52.130112] RSP: 002b:00007fadff57ddb8 EFLAGS: 00000297 ORIG_RAX: 000000000000002e [ 52.137804] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446389 [ 52.145154] RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000005 [ 52.152446] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 52.159703] R10: 0000000000000000 R11: 0000000000000297 R12: 00000000006dac3c [ 52.166954] R13: 00007ffc6c50142f R14: 00007fadff57e9c0 R15: 00000000006dad2c [ 52.175131] Kernel Offset: disabled [ 52.178752] Rebooting in 86400 seconds..