[ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Started Getty on tty2. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.115' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 73.013864][ T8401] [ 73.016477][ T8401] ============================= [ 73.022101][ T8401] WARNING: suspicious RCU usage [ 73.026965][ T8401] 5.12.0-rc4-syzkaller #0 Not tainted [ 73.032457][ T8401] ----------------------------- [ 73.037381][ T8401] include/net/addrconf.h:314 suspicious rcu_dereference_check() usage! [ 73.045826][ T8401] [ 73.045826][ T8401] other info that might help us debug this: [ 73.045826][ T8401] [ 73.056171][ T8401] [ 73.056171][ T8401] rcu_scheduler_active = 2, debug_locks = 1 [ 73.064583][ T8401] 1 lock held by syz-executor176/8401: [ 73.070292][ T8401] #0: ffff888021f79860 (sk_lock-AF_INET6){+.+.}-{0:0}, at: ipv6_get_msfilter+0xf8/0x220 [ 73.080325][ T8401] [ 73.080325][ T8401] stack backtrace: [ 73.086228][ T8401] CPU: 1 PID: 8401 Comm: syz-executor176 Not tainted 5.12.0-rc4-syzkaller #0 [ 73.094982][ T8401] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.105043][ T8401] Call Trace: [ 73.108339][ T8401] dump_stack+0x141/0x1d7 [ 73.112689][ T8401] ip6_mc_find_dev_rtnl+0x1be/0x1f0 [ 73.117899][ T8401] ip6_mc_msfget+0x1be/0x830 [ 73.122496][ T8401] ? ipv6_sock_mc_join_ssm+0x30/0x30 [ 73.127773][ T8401] ? lock_release+0x720/0x720 [ 73.132443][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.137295][ T8401] ? do_raw_spin_lock+0x120/0x2b0 [ 73.142344][ T8401] ? mark_held_locks+0x9f/0xe0 [ 73.147129][ T8401] ? __local_bh_enable_ip+0xa0/0x120 [ 73.152438][ T8401] ipv6_get_msfilter+0x10c/0x220 [ 73.157609][ T8401] ? compat_ipv6_get_msfilter+0x3b0/0x3b0 [ 73.163350][ T8401] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 73.169345][ T8401] ? __might_fault+0xd3/0x180 [ 73.174033][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.178942][ T8401] do_ipv6_getsockopt.constprop.0+0x1675/0x2660 [ 73.185227][ T8401] ? do_ipv6_mcast_group_source+0x240/0x240 [ 73.191126][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.196786][ T8401] ? ipv6_getsockopt+0x120/0x270 [ 73.201724][ T8401] ipv6_getsockopt+0x13c/0x270 [ 73.206498][ T8401] ? do_ipv6_getsockopt.constprop.0+0x2660/0x2660 [ 73.213091][ T8401] ? sock_def_destruct+0x10/0x10 [ 73.218029][ T8401] udpv6_getsockopt+0x5d/0x90 [ 73.222974][ T8401] __sys_getsockopt+0x21f/0x5f0 [ 73.227845][ T8401] ? __ia32_sys_setsockopt+0x150/0x150 [ 73.233303][ T8401] __x64_sys_getsockopt+0xba/0x150 [ 73.238530][ T8401] ? syscall_enter_from_user_mode+0x27/0x70 [ 73.245618][ T8401] do_syscall_64+0x2d/0x70 [ 73.250060][ T8401] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 73.256148][ T8401] RIP: 0033:0x43efc9 [ 73.260375][ T8401] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 73.280215][ T8401] RSP: 002b:00007fff4d87b358 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 [ 73.288660][ T8401] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043efc9 [ 73.296646][ T8401] RDX: 0000000000000030 RSI: 0000000000000029 RDI: 0000000000000003 [ 73.304744][ T8401] RBP: 0000000000402fb0 R08: 0000000020001000 R09: 0000000000400488 [ 73.312852][ T8401] R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000403040 [ 73.320845][ T8401] R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488 [ 73.329540][ T8401] [ 73.331892][ T8401] ============================= [ 73.336753][ T8401] WARNING: suspicious RCU usage [ 73.341864][ T8401] 5.12.0-rc4-syzkaller #0 Not tainted [ 73.347268][ T8401] ----------------------------- [ 73.352259][ T8401] net/ipv6/mcast.c:600 suspicious rcu_dereference_protected() usage! [ 73.360434][ T8401] [ 73.360434][ T8401] other info that might help us debug this: [ 73.360434][ T8401] [ 73.370805][ T8401] [ 73.370805][ T8401] rcu_scheduler_active = 2, debug_locks = 1 [ 73.379070][ T8401] 1 lock held by syz-executor176/8401: [ 73.384561][ T8401] #0: ffff888021f79860 (sk_lock-AF_INET6){+.+.}-{0:0}, at: ipv6_get_msfilter+0xf8/0x220 [ 73.394571][ T8401] [ 73.394571][ T8401] stack backtrace: [ 73.400572][ T8401] CPU: 1 PID: 8401 Comm: syz-executor176 Not tainted 5.12.0-rc4-syzkaller #0 [ 73.409372][ T8401] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.419426][ T8401] Call Trace: [ 73.422725][ T8401] dump_stack+0x141/0x1d7 [ 73.427061][ T8401] ip6_mc_msfget+0x672/0x830 [ 73.431768][ T8401] ? ipv6_sock_mc_join_ssm+0x30/0x30 [ 73.437061][ T8401] ? lock_release+0x720/0x720 [ 73.441834][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.446698][ T8401] ? do_raw_spin_lock+0x120/0x2b0 [ 73.451738][ T8401] ? mark_held_locks+0x9f/0xe0 [ 73.456508][ T8401] ? __local_bh_enable_ip+0xa0/0x120 [ 73.461811][ T8401] ipv6_get_msfilter+0x10c/0x220 [ 73.466769][ T8401] ? compat_ipv6_get_msfilter+0x3b0/0x3b0 [ 73.472642][ T8401] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 73.478649][ T8401] ? __might_fault+0xd3/0x180 [ 73.483369][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.488250][ T8401] do_ipv6_getsockopt.constprop.0+0x1675/0x2660 [ 73.495372][ T8401] ? do_ipv6_mcast_group_source+0x240/0x240 [ 73.501363][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.506242][ T8401] ? ipv6_getsockopt+0x120/0x270 [ 73.511195][ T8401] ipv6_getsockopt+0x13c/0x270 [ 73.515954][ T8401] ? do_ipv6_getsockopt.constprop.0+0x2660/0x2660 [ 73.522398][ T8401] ? sock_def_destruct+0x10/0x10 [ 73.529068][ T8401] udpv6_getsockopt+0x5d/0x90 [ 73.533751][ T8401] __sys_getsockopt+0x21f/0x5f0 [ 73.538868][ T8401] ? __ia32_sys_setsockopt+0x150/0x150 [ 73.544342][ T8401] __x64_sys_getsockopt+0xba/0x150 [ 73.549481][ T8401] ? syscall_enter_from_user_mode+0x27/0x70 [ 73.555468][ T8401] do_syscall_64+0x2d/0x70 [ 73.559887][ T8401] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 73.565782][ T8401] RIP: 0033:0x43efc9 [ 73.569682][ T8401] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 73.589302][ T8401] RSP: 002b:00007fff4d87b358 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 [ 73.597849][ T8401] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043efc9 [ 73.605827][ T8401] RDX: 0000000000000030 RSI: 0000000000000029 RDI: 0000000000000003 [ 73.613814][ T8401] RBP: 0000000000402fb0 R08: 0000000020001000 R09: 0000000000400488 [ 73.621782][ T8401] R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000403040 [ 73.629763][ T8401] R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488 [ 73.638243][ T8401] [ 73.640598][ T8401] ============================= [ 73.645462][ T8401] WARNING: suspicious RCU usage [ 73.650698][ T8401] 5.12.0-rc4-syzkaller #0 Not tainted [ 73.656100][ T8401] ----------------------------- [ 73.661219][ T8401] net/ipv6/mcast.c:610 suspicious rcu_dereference_protected() usage! [ 73.669402][ T8401] [ 73.669402][ T8401] other info that might help us debug this: [ 73.669402][ T8401] [ 73.679743][ T8401] [ 73.679743][ T8401] rcu_scheduler_active = 2, debug_locks = 1 [ 73.687856][ T8401] 1 lock held by syz-executor176/8401: [ 73.693445][ T8401] #0: ffff888021f79860 (sk_lock-AF_INET6){+.+.}-{0:0}, at: ipv6_get_msfilter+0xf8/0x220 [ 73.703696][ T8401] [ 73.703696][ T8401] stack backtrace: [ 73.709708][ T8401] CPU: 1 PID: 8401 Comm: syz-executor176 Not tainted 5.12.0-rc4-syzkaller #0 [ 73.718491][ T8401] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.728555][ T8401] Call Trace: [ 73.731848][ T8401] dump_stack+0x141/0x1d7 [ 73.736369][ T8401] ip6_mc_msfget+0x6da/0x830 [ 73.740964][ T8401] ? ipv6_sock_mc_join_ssm+0x30/0x30 [ 73.746353][ T8401] ? lock_release+0x720/0x720 [ 73.751048][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.755893][ T8401] ? do_raw_spin_lock+0x120/0x2b0 [ 73.760917][ T8401] ? mark_held_locks+0x9f/0xe0 [ 73.766305][ T8401] ? __local_bh_enable_ip+0xa0/0x120 [ 73.771584][ T8401] ipv6_get_msfilter+0x10c/0x220 [ 73.776516][ T8401] ? compat_ipv6_get_msfilter+0x3b0/0x3b0 [ 73.782566][ T8401] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 73.788559][ T8401] ? __might_fault+0xd3/0x180 [ 73.793253][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.798111][ T8401] do_ipv6_getsockopt.constprop.0+0x1675/0x2660 [ 73.804464][ T8401] ? do_ipv6_mcast_group_source+0x240/0x240 [ 73.810634][ T8401] ? lock_downgrade+0x6e0/0x6e0 [ 73.815689][ T8401] ? ipv6_getsockopt+0x120/0x270 [ 73.820853][ T8401] ipv6_getsockopt+0x13c/0x270 [ 73.826842][ T8401] ? do_ipv6_getsockopt.constprop.0+0x2660/0x2660 [ 73.833292][ T8401] ? sock_def_destruct+0x10/0x10 [ 73.838324][ T8401] udpv6_getsockopt+0x5d/0x90 [ 73.843018][ T8401] __sys_getsockopt+0x21f/0x5f0 [ 73.848160][ T8401] ? __ia32_sys_setsockopt+0x150/0x150 [ 73.853638][ T8401] __x64_sys_getsockopt+0xba/0x150 [ 73.858835][ T8401] ? syscall_enter_from_user_mode+0x27/0x70 [ 73.864832][ T8401] do_syscall_64+0x2d/0x70 [ 73.869254][ T8401] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 73.875154][ T8401] RIP: 0033:0x43efc9 [ 73.879057][ T8401] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 73.898673][ T8401] RSP: 002b:00007fff4d87b358 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 [ 73.907127][ T8401] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043efc9 [ 73.915728][ T8401]