[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [ 17.561647] mcstransd (4139) used greatest stack depth: 16488 bytes left Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 18.863224] audit: type=1400 audit(1520643704.704:6): avc: denied { map } for pid=4231 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.8' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 net.ipv6.conf.syz_tun.router_solicitations = 0 syzkaller login: [ 25.224821] audit: type=1400 audit(1520643711.065:7): avc: denied { map } for pid=4245 comm="syzkaller532165" path="/root/syzkaller532165848" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 25.234654] IPVS: ftp: loaded support on port[0] = 21 RTNETLINK answers: File exists RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 25.507565] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready 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 [ 25.864853] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 25.870950] 8021q: adding VLAN 0 to HW filter on device bond0 executing program [ 25.909711] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 25.948612] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 25.959046] ================================================================== [ 25.966516] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 25.972635] Read of size 8 at addr ffff8801b3442c18 by task syzkaller532165/4246 [ 25.980132] [ 25.981735] CPU: 1 PID: 4246 Comm: syzkaller532165 Not tainted 4.16.0-rc4+ #259 [ 25.989150] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.998474] Call Trace: [ 26.001039] dump_stack+0x194/0x24d [ 26.004642] ? arch_local_irq_restore+0x53/0x53 [ 26.009287] ? show_regs_print_info+0x18/0x18 [ 26.013760] ? ip6_xmit+0x1f76/0x2260 [ 26.017538] print_address_description+0x73/0x250 [ 26.022352] ? ip6_xmit+0x1f76/0x2260 [ 26.026125] kasan_report+0x23c/0x360 [ 26.029902] __asan_report_load8_noabort+0x14/0x20 [ 26.034803] ip6_xmit+0x1f76/0x2260 [ 26.038413] ? ip6_finish_output2+0x23d0/0x23d0 [ 26.043064] ? fl6_update_dst+0x127/0x2b0 [ 26.047190] ? inet6_csk_route_socket+0x691/0xe80 [ 26.052023] ? trace_hardirqs_off+0x10/0x10 [ 26.056323] ? lock_acquire+0x1d5/0x580 [ 26.060267] ? lock_acquire+0x1d5/0x580 [ 26.064212] ? inet6_csk_xmit+0x114/0x580 [ 26.068331] ? trace_hardirqs_off+0x10/0x10 [ 26.072629] ? lock_release+0xa40/0xa40 [ 26.076590] inet6_csk_xmit+0x2fc/0x580 [ 26.080536] ? inet6_csk_update_pmtu+0x160/0x160 [ 26.085266] ? __sk_dst_check+0x1a5/0x380 [ 26.089389] ? sock_kzfree_s+0x60/0x60 [ 26.093262] l2tp_xmit_skb+0x105f/0x1410 [ 26.097305] ? l2tp_session_create+0xb80/0xb80 [ 26.101859] ? sock_wmalloc+0x15d/0x1d0 [ 26.105809] ? iov_iter_advance+0x13f0/0x13f0 [ 26.110281] ? pppol2tp_sendmsg+0x41b/0x670 [ 26.114578] pppol2tp_sendmsg+0x470/0x670 [ 26.118702] ? selinux_socket_sendmsg+0x36/0x40 [ 26.123344] ? pppol2tp_getsockopt+0x900/0x900 [ 26.127901] sock_sendmsg+0xca/0x110 [ 26.131589] SYSC_sendto+0x361/0x5c0 [ 26.135276] ? SYSC_connect+0x4a0/0x4a0 [ 26.139237] ? __do_page_fault+0x5f7/0xc90 [ 26.143450] ? lock_downgrade+0x980/0x980 [ 26.147576] ? handle_mm_fault+0x465/0xb10 [ 26.151784] ? check_same_owner+0x320/0x320 [ 26.156104] ? mm_fault_error+0x2c0/0x2c0 [ 26.160227] ? move_addr_to_kernel+0x60/0x60 [ 26.164611] SyS_sendto+0x40/0x50 [ 26.168045] ? SyS_getpeername+0x30/0x30 [ 26.172088] do_syscall_64+0x281/0x940 [ 26.175946] ? __do_page_fault+0xc90/0xc90 [ 26.180156] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.184884] ? syscall_return_slowpath+0x550/0x550 [ 26.189785] ? syscall_return_slowpath+0x2ac/0x550 [ 26.194689] ? prepare_exit_to_usermode+0x350/0x350 [ 26.199683] ? retint_user+0x18/0x18 [ 26.203374] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.208196] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 26.213355] RIP: 0033:0x441ab9 [ 26.216518] RSP: 002b:00007ffe98b28188 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 26.224204] RAX: ffffffffffffffda RBX: 000000000000001a RCX: 0000000000441ab9 [ 26.231447] RDX: 0000000000000000 RSI: 0000000020de7000 RDI: 0000000000000004 [ 26.238695] RBP: 00000000004a3d0e R08: 000000002064eff0 R09: 0000000000000080 [ 26.245942] R10: c3fe68eda9554f8b R11: 0000000000000212 R12: 00007ffe98b28280 [ 26.253197] R13: 00000000004027e0 R14: 0000000000000000 R15: 0000000000000000 [ 26.260464] [ 26.262071] Allocated by task 4238: [ 26.265678] save_stack+0x43/0xd0 [ 26.269107] kasan_kmalloc+0xad/0xe0 [ 26.272797] kasan_slab_alloc+0x12/0x20 [ 26.276741] kmem_cache_alloc+0x12e/0x760 [ 26.280858] dst_alloc+0x11f/0x1a0 [ 26.284368] rt_dst_alloc+0xe9/0x4e0 [ 26.288069] ip_route_output_key_hash_rcu+0xa59/0x2fe0 [ 26.293322] ip_route_output_key_hash+0x20b/0x370 [ 26.298136] __ip4_datagram_connect+0xa67/0x1240 [ 26.302862] __ip6_datagram_connect+0x749/0x12d0 [ 26.307586] ip6_datagram_connect+0x2f/0x50 [ 26.311879] inet_dgram_connect+0x16b/0x1f0 [ 26.316175] SYSC_connect+0x213/0x4a0 [ 26.319953] SyS_connect+0x24/0x30 [ 26.323462] do_syscall_64+0x281/0x940 [ 26.327321] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 26.332477] [ 26.334075] Freed by task 4238: [ 26.337325] save_stack+0x43/0xd0 [ 26.340747] __kasan_slab_free+0x11a/0x170 [ 26.344950] kasan_slab_free+0xe/0x10 [ 26.348728] kmem_cache_free+0x83/0x2a0 [ 26.352678] dst_destroy+0x257/0x370 [ 26.356361] dst_destroy_rcu+0x16/0x20 [ 26.360223] rcu_process_callbacks+0xd6c/0x17f0 [ 26.364861] __do_softirq+0x2d7/0xb85 [ 26.368627] [ 26.370227] The buggy address belongs to the object at ffff8801b3442c00 [ 26.370227] which belongs to the cache ip_dst_cache of size 160 [ 26.382938] The buggy address is located 24 bytes inside of [ 26.382938] 160-byte region [ffff8801b3442c00, ffff8801b3442ca0) [ 26.394709] The buggy address belongs to the page: [ 26.399614] page:ffffea0006cd1080 count:1 mapcount:0 mapping:ffff8801b3442000 index:0xffff8801b3442000 [ 26.409032] flags: 0x2fffc0000000100(slab) [ 26.413242] raw: 02fffc0000000100 ffff8801b3442000 ffff8801b3442000 000000010000000a [ 26.421094] raw: ffffea0006c973a0 ffff8801d5421d38 ffff8801d5420680 0000000000000000 [ 26.428941] page dumped because: kasan: bad access detected [ 26.434630] [ 26.436230] Memory state around the buggy address: [ 26.441131] ffff8801b3442b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.448464] ffff8801b3442b80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 26.455796] >ffff8801b3442c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.463125] ^ [ 26.467244] ffff8801b3442c80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc [ 26.474574] ffff8801b3442d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.481900] ================================================================== [ 26.489244] Disabling lock debugging due to kernel taint [ 26.494692] Kernel panic - not syncing: panic_on_warn set ... [ 26.494692] [ 26.502040] CPU: 1 PID: 4246 Comm: syzkaller532165 Tainted: G B 4.16.0-rc4+ #259 [ 26.510761] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.520085] Call Trace: [ 26.522650] dump_stack+0x194/0x24d [ 26.526249] ? arch_local_irq_restore+0x53/0x53 [ 26.530886] ? kasan_end_report+0x32/0x50 [ 26.535004] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.539735] ? vsnprintf+0x1ed/0x1900 [ 26.543506] ? ip6_xmit+0x1e90/0x2260 [ 26.547288] panic+0x1e4/0x41c [ 26.550451] ? refcount_error_report+0x214/0x214 [ 26.555202] ? add_taint+0x1c/0x50 [ 26.558735] ? add_taint+0x1c/0x50 [ 26.562249] ? ip6_xmit+0x1f76/0x2260 [ 26.566195] kasan_end_report+0x50/0x50 [ 26.570138] kasan_report+0x149/0x360 [ 26.573910] __asan_report_load8_noabort+0x14/0x20 [ 26.578807] ip6_xmit+0x1f76/0x2260 [ 26.582411] ? ip6_finish_output2+0x23d0/0x23d0 [ 26.587056] ? fl6_update_dst+0x127/0x2b0 [ 26.591178] ? inet6_csk_route_socket+0x691/0xe80 [ 26.596005] ? trace_hardirqs_off+0x10/0x10 [ 26.600323] ? lock_acquire+0x1d5/0x580 [ 26.604288] ? lock_acquire+0x1d5/0x580 [ 26.608260] ? inet6_csk_xmit+0x114/0x580 [ 26.612400] ? trace_hardirqs_off+0x10/0x10 [ 26.616715] ? lock_release+0xa40/0xa40 [ 26.620699] inet6_csk_xmit+0x2fc/0x580 [ 26.624660] ? inet6_csk_update_pmtu+0x160/0x160 [ 26.629392] ? __sk_dst_check+0x1a5/0x380 [ 26.633515] ? sock_kzfree_s+0x60/0x60 [ 26.637382] l2tp_xmit_skb+0x105f/0x1410 [ 26.641432] ? l2tp_session_create+0xb80/0xb80 [ 26.645985] ? sock_wmalloc+0x15d/0x1d0 [ 26.649932] ? iov_iter_advance+0x13f0/0x13f0 [ 26.654406] ? pppol2tp_sendmsg+0x41b/0x670 [ 26.658700] pppol2tp_sendmsg+0x470/0x670 [ 26.662821] ? selinux_socket_sendmsg+0x36/0x40 [ 26.667464] ? pppol2tp_getsockopt+0x900/0x900 [ 26.672024] sock_sendmsg+0xca/0x110 [ 26.675720] SYSC_sendto+0x361/0x5c0 [ 26.679407] ? SYSC_connect+0x4a0/0x4a0 [ 26.683357] ? __do_page_fault+0x5f7/0xc90 [ 26.687562] ? lock_downgrade+0x980/0x980 [ 26.691682] ? handle_mm_fault+0x465/0xb10 [ 26.695891] ? check_same_owner+0x320/0x320 [ 26.700199] ? mm_fault_error+0x2c0/0x2c0 [ 26.704323] ? move_addr_to_kernel+0x60/0x60 [ 26.708703] SyS_sendto+0x40/0x50 [ 26.712126] ? SyS_getpeername+0x30/0x30 [ 26.716160] do_syscall_64+0x281/0x940 [ 26.720023] ? __do_page_fault+0xc90/0xc90 [ 26.724245] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.728973] ? syscall_return_slowpath+0x550/0x550 [ 26.733886] ? syscall_return_slowpath+0x2ac/0x550 [ 26.738789] ? prepare_exit_to_usermode+0x350/0x350 [ 26.743784] ? retint_user+0x18/0x18 [ 26.747480] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.752299] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 26.757463] RIP: 0033:0x441ab9 [ 26.760635] RSP: 002b:00007ffe98b28188 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 26.768314] RAX: ffffffffffffffda RBX: 000000000000001a RCX: 0000000000441ab9 [ 26.775557] RDX: 0000000000000000 RSI: 0000000020de7000 RDI: 0000000000000004 [ 26.782799] RBP: 00000000004a3d0e R08: 000000002064eff0 R09: 0000000000000080 [ 26.790043] R10: c3fe68eda9554f8b R11: 0000000000000212 R12: 00007ffe98b28280 [ 26.797285] R13: 00000000004027e0 R14: 0000000000000000 R15: 0000000000000000 [ 26.804994] Dumping ftrace buffer: [ 26.808505] (ftrace buffer empty) [ 26.812184] Kernel Offset: disabled [ 26.815780] Rebooting in 86400 seconds..