[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.314659] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 22.698261] random: sshd: uninitialized urandom read (32 bytes read) [ 23.010103] random: sshd: uninitialized urandom read (32 bytes read) [ 23.851173] random: sshd: uninitialized urandom read (32 bytes read) [ 40.547875] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.38' (ECDSA) to the list of known hosts. [ 46.001631] random: sshd: uninitialized urandom read (32 bytes read) [ 46.100727] IPVS: ftp: loaded support on port[0] = 21 [ 46.227368] bridge0: port 1(bridge_slave_0) entered blocking state [ 46.233877] bridge0: port 1(bridge_slave_0) entered disabled state [ 46.241149] device bridge_slave_0 entered promiscuous mode [ 46.257797] bridge0: port 2(bridge_slave_1) entered blocking state [ 46.264254] bridge0: port 2(bridge_slave_1) entered disabled state [ 46.271304] device bridge_slave_1 entered promiscuous mode [ 46.287073] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 46.302951] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 46.347420] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 46.365126] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 46.426637] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 46.433901] team0: Port device team_slave_0 added [ 46.448134] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 46.455550] team0: Port device team_slave_1 added [ 46.470820] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 46.487392] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 46.503627] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 46.519539] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 46.634555] bridge0: port 2(bridge_slave_1) entered blocking state [ 46.641061] bridge0: port 2(bridge_slave_1) entered forwarding state [ 46.647909] bridge0: port 1(bridge_slave_0) entered blocking state [ 46.654277] bridge0: port 1(bridge_slave_0) entered forwarding state RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 47.064862] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 47.071818] 8021q: adding VLAN 0 to HW filter on device bond0 [ 47.115808] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 47.159398] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 47.167163] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 47.204448] 8021q: adding VLAN 0 to HW filter on device team0 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 50.160892] ------------[ cut here ]------------ [ 50.165939] refcount_t: underflow; use-after-free. [ 50.171110] WARNING: CPU: 1 PID: 4765 at lib/refcount.c:187 refcount_sub_and_test+0x2e7/0x350 [ 50.179769] Kernel panic - not syncing: panic_on_warn set ... [ 50.179769] [ 50.187126] CPU: 1 PID: 4765 Comm: syz-executor745 Not tainted 4.18.0-rc3+ #134 [ 50.194581] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.203926] Call Trace: [ 50.206516] dump_stack+0x1c9/0x2b4 [ 50.210141] ? dump_stack_print_info.cold.2+0x52/0x52 [ 50.215361] panic+0x238/0x4e7 [ 50.218546] ? add_taint.cold.5+0x16/0x16 [ 50.222686] ? __warn.cold.8+0x148/0x1ba [ 50.226738] ? __warn.cold.8+0x117/0x1ba [ 50.230906] ? refcount_sub_and_test+0x2e7/0x350 [ 50.235752] __warn.cold.8+0x163/0x1ba [ 50.239644] ? refcount_sub_and_test+0x2e7/0x350 [ 50.244388] report_bug+0x252/0x2d0 [ 50.248003] do_error_trap+0x1fc/0x4d0 [ 50.251895] ? math_error+0x3e0/0x3e0 [ 50.255683] ? vprintk_default+0x28/0x30 [ 50.259739] ? vprintk_func+0x81/0xe7 [ 50.263527] ? printk+0xa7/0xcf [ 50.266796] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 50.271630] do_invalid_op+0x1b/0x20 [ 50.275339] invalid_op+0x14/0x20 [ 50.278780] RIP: 0010:refcount_sub_and_test+0x2e7/0x350 [ 50.284132] Code: 89 de e8 6c b5 1c fe 84 db 74 07 31 db e9 46 ff ff ff e8 8c b4 1c fe 48 c7 c7 c0 41 1a 88 c6 05 96 65 3a 06 01 e8 59 d7 e7 fd <0f> 0b 31 db e9 25 ff ff ff 48 8b bd 28 ff ff ff 89 85 34 ff ff ff [ 50.303318] RSP: 0018:ffff8801d606f780 EFLAGS: 00010286 [ 50.308685] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 50.315949] RDX: 0000000000000000 RSI: ffffffff81631851 RDI: ffff8801d606f458 [ 50.323220] RBP: ffff8801d606f868 R08: ffff8801d7d3e4c0 R09: 0000000000000006 [ 50.330478] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffff [ 50.337738] R13: ffff8801d606f840 R14: 0000000000000001 R15: ffff8801cd4d4980 [ 50.345039] ? vprintk_func+0x81/0xe7 [ 50.348844] ? refcount_inc_not_zero+0x2f0/0x2f0 [ 50.353595] ? graph_lock+0x170/0x170 [ 50.357408] ? __lock_is_held+0xb5/0x140 [ 50.361469] refcount_dec_and_test+0x1a/0x20 [ 50.365866] smap_release_sock+0x76/0x320 [ 50.370000] ? sock_map_alloc+0x410/0x410 [ 50.374158] sock_hash_ctx_update_elem.isra.27+0x8cb/0x1690 [ 50.379892] ? sock_map_free+0x530/0x530 [ 50.383955] ? rcu_is_watching+0x8c/0x150 [ 50.388117] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 50.392537] ? __fget+0x414/0x670 [ 50.395997] ? expand_files.part.8+0x9c0/0x9c0 [ 50.400586] ? find_held_lock+0x36/0x1c0 [ 50.404653] sock_hash_update_elem+0x157/0x2f0 [ 50.409244] ? bpf_sock_hash_update+0x90/0x90 [ 50.413735] ? kasan_check_read+0x11/0x20 [ 50.417879] ? rcu_is_watching+0x8c/0x150 [ 50.422030] ? rcu_report_qs_rnp+0x7a0/0x7a0 [ 50.426448] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 50.431985] ? bpf_sock_hash_update+0x90/0x90 [ 50.436477] map_update_elem+0x5c4/0xc90 [ 50.440525] __x64_sys_bpf+0x32d/0x510 [ 50.444398] ? bpf_prog_get+0x20/0x20 [ 50.448183] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 50.453732] ? do_syscall_64+0x9a/0x820 [ 50.457709] do_syscall_64+0x1b9/0x820 [ 50.461592] ? finish_task_switch+0x1d3/0x890 [ 50.466075] ? syscall_return_slowpath+0x5e0/0x5e0 [ 50.470989] ? syscall_return_slowpath+0x31d/0x5e0 [ 50.475931] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 50.481282] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 50.486122] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 50.491296] RIP: 0033:0x4468f9 [ 50.494479] Code: e8 cc c0 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 1b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 50.513668] RSP: 002b:00007ff287729db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 [ 50.521379] RAX: ffffffffffffffda RBX: 00000000006dcc3c RCX: 00000000004468f9 [ 50.528638] RDX: 0000000000000020 RSI: 0000000020000180 RDI: 0000000000000002 [ 50.535904] RBP: 00000000006dcc38 R08: 0000000000000000 R09: 0000000000000000 [ 50.543183] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 50.550442] R13: 00007ffc14e9798f R14: 00007ff28772a9c0 R15: 0000000000000005 [ 50.558483] Dumping ftrace buffer: [ 50.562133] (ftrace buffer empty) [ 50.565909] Kernel Offset: disabled [ 50.569519] Rebooting in 86400 seconds..