[....] Starting enhanced syslogd: rsyslogd[ 15.037848] audit: type=1400 audit(1521003052.108:5): avc: denied { syslog } for pid=4071 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.463685] audit: type=1400 audit(1521003055.534:6): avc: denied { map } for pid=4211 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 Warning: Permanently added '10.128.0.34' (ECDSA) to the list of known hosts. executing program [ 43.825769] audit: type=1400 audit(1521003080.896:7): avc: denied { map } for pid=4229 comm="syzkaller027315" path="/root/syzkaller027315833" 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 [ 43.829570] ================================================================== [ 43.859318] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 43.865436] Read of size 8 at addr ffff8801b9f95e18 by task syzkaller027315/4229 [ 43.872950] [ 43.874573] CPU: 0 PID: 4229 Comm: syzkaller027315 Not tainted 4.16.0-rc5+ #352 [ 43.881997] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.891334] Call Trace: [ 43.893900] dump_stack+0x194/0x24d [ 43.897505] ? arch_local_irq_restore+0x53/0x53 [ 43.902157] ? show_regs_print_info+0x18/0x18 [ 43.906632] ? ip6_xmit+0x1f76/0x2260 [ 43.910409] print_address_description+0x73/0x250 [ 43.915224] ? ip6_xmit+0x1f76/0x2260 [ 43.918998] kasan_report+0x23c/0x360 [ 43.922776] __asan_report_load8_noabort+0x14/0x20 [ 43.927676] ip6_xmit+0x1f76/0x2260 [ 43.931286] ? ip6_finish_output2+0x23a0/0x23a0 [ 43.935929] ? fl6_update_dst+0x127/0x2b0 [ 43.940053] ? inet6_csk_route_socket+0x691/0xe80 [ 43.944871] ? trace_hardirqs_off+0x10/0x10 [ 43.949167] ? lock_acquire+0x1d5/0x580 [ 43.953115] ? lock_acquire+0x1d5/0x580 [ 43.957058] ? inet6_csk_xmit+0x114/0x580 [ 43.961191] ? trace_hardirqs_off+0x10/0x10 [ 43.965496] ? lock_release+0xa40/0xa40 [ 43.969459] inet6_csk_xmit+0x2fc/0x580 [ 43.973411] ? inet6_csk_update_pmtu+0x160/0x160 [ 43.978138] ? __sk_dst_check+0x1a5/0x380 [ 43.982344] ? sock_kfree_s+0x60/0x60 [ 43.986139] l2tp_xmit_skb+0x105f/0x1410 [ 43.990186] ? l2tp_session_create+0xb80/0xb80 [ 43.994747] ? sock_wmalloc+0x15d/0x1d0 [ 43.998702] ? iov_iter_advance+0x13f0/0x13f0 [ 44.003173] ? pppol2tp_sendmsg+0x41b/0x670 [ 44.007470] pppol2tp_sendmsg+0x470/0x670 [ 44.011590] ? selinux_socket_sendmsg+0x36/0x40 [ 44.016234] ? pppol2tp_getsockopt+0x900/0x900 [ 44.020788] sock_sendmsg+0xca/0x110 [ 44.024475] SYSC_sendto+0x361/0x5c0 [ 44.028170] ? SYSC_connect+0x4a0/0x4a0 [ 44.032132] ? inet_dgram_connect+0x172/0x1f0 [ 44.036615] ? SYSC_connect+0x2e0/0x4a0 [ 44.040586] ? mm_fault_error+0x2c0/0x2c0 [ 44.044704] ? move_addr_to_kernel+0x60/0x60 [ 44.049088] SyS_sendto+0x40/0x50 [ 44.052521] ? SyS_getpeername+0x30/0x30 [ 44.056569] do_syscall_64+0x281/0x940 [ 44.060427] ? __do_page_fault+0xc90/0xc90 [ 44.064636] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 44.069367] ? syscall_return_slowpath+0x550/0x550 [ 44.074271] ? syscall_return_slowpath+0x2ac/0x550 [ 44.079171] ? prepare_exit_to_usermode+0x350/0x350 [ 44.084163] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 44.089506] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.094325] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.099487] RIP: 0033:0x43ff49 [ 44.102646] RSP: 002b:00007ffde3acb6a8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c [ 44.110324] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 44.117566] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 44.124806] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 44.132047] R10: 0000000000040001 R11: 0000000000000216 R12: 0000000000401870 [ 44.139292] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 44.146557] [ 44.148163] Allocated by task 3895: [ 44.151771] save_stack+0x43/0xd0 [ 44.155196] kasan_kmalloc+0xad/0xe0 [ 44.158880] kasan_slab_alloc+0x12/0x20 [ 44.162835] kmem_cache_alloc+0x12e/0x760 [ 44.166956] dst_alloc+0x11f/0x1a0 [ 44.170468] rt_dst_alloc+0xe9/0x520 [ 44.174154] ip_route_input_rcu+0x1076/0x3200 [ 44.178618] ip_route_input_noref+0xf5/0x1e0 [ 44.182998] ip_rcv_finish+0x3a6/0x2040 [ 44.186942] ip_rcv+0xb76/0x1820 [ 44.190280] __netif_receive_skb_core+0x1a41/0x3460 [ 44.195271] __netif_receive_skb+0x2c/0x1b0 [ 44.199564] netif_receive_skb_internal+0x10b/0x670 [ 44.204559] napi_gro_receive+0x3d0/0x500 [ 44.208677] receive_buf+0xb6f/0x2530 [ 44.212446] virtnet_poll+0x320/0xb70 [ 44.216215] net_rx_action+0x792/0x1910 [ 44.220158] __do_softirq+0x2d7/0xb85 [ 44.223937] [ 44.225533] Freed by task 0: [ 44.228522] save_stack+0x43/0xd0 [ 44.231943] __kasan_slab_free+0x11a/0x170 [ 44.236159] kasan_slab_free+0xe/0x10 [ 44.239949] kmem_cache_free+0x83/0x2a0 [ 44.243898] dst_destroy+0x257/0x370 [ 44.247581] dst_destroy_rcu+0x16/0x20 [ 44.251442] rcu_process_callbacks+0xd6c/0x17f0 [ 44.256081] __do_softirq+0x2d7/0xb85 [ 44.259848] [ 44.261446] The buggy address belongs to the object at ffff8801b9f95e00 [ 44.261446] which belongs to the cache ip_dst_cache of size 168 [ 44.274158] The buggy address is located 24 bytes inside of [ 44.274158] 168-byte region [ffff8801b9f95e00, ffff8801b9f95ea8) [ 44.285917] The buggy address belongs to the page: [ 44.290819] page:ffffea0006e7e540 count:1 mapcount:0 mapping:ffff8801b9f95000 index:0x0 [ 44.298950] flags: 0x2fffc0000000100(slab) [ 44.303159] raw: 02fffc0000000100 ffff8801b9f95000 0000000000000000 0000000100000010 [ 44.311017] raw: ffff8801d6bda348 ffff8801d6bda348 ffff8801d5bb9c80 0000000000000000 [ 44.318878] page dumped because: kasan: bad access detected [ 44.324564] [ 44.326164] Memory state around the buggy address: [ 44.331083] ffff8801b9f95d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 44.338411] ffff8801b9f95d80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 44.345835] >ffff8801b9f95e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.353162] ^ [ 44.357283] ffff8801b9f95e80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc [ 44.364618] ffff8801b9f95f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.371943] ================================================================== [ 44.379271] Disabling lock debugging due to kernel taint [ 44.384723] Kernel panic - not syncing: panic_on_warn set ... [ 44.384723] [ 44.392060] CPU: 0 PID: 4229 Comm: syzkaller027315 Tainted: G B 4.16.0-rc5+ #352 [ 44.400777] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.410102] Call Trace: [ 44.412666] dump_stack+0x194/0x24d [ 44.416264] ? arch_local_irq_restore+0x53/0x53 [ 44.420901] ? kasan_end_report+0x32/0x50 [ 44.425021] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 44.429744] ? vsnprintf+0x1ed/0x1900 [ 44.433524] ? ip6_xmit+0x1f30/0x2260 [ 44.437294] panic+0x1e4/0x41c [ 44.440454] ? refcount_error_report+0x214/0x214 [ 44.445184] ? add_taint+0x1c/0x50 [ 44.448692] ? add_taint+0x1c/0x50 [ 44.452200] ? ip6_xmit+0x1f76/0x2260 [ 44.455968] kasan_end_report+0x50/0x50 [ 44.459910] kasan_report+0x149/0x360 [ 44.463695] __asan_report_load8_noabort+0x14/0x20 [ 44.468593] ip6_xmit+0x1f76/0x2260 [ 44.472195] ? ip6_finish_output2+0x23a0/0x23a0 [ 44.476831] ? fl6_update_dst+0x127/0x2b0 [ 44.480951] ? inet6_csk_route_socket+0x691/0xe80 [ 44.485764] ? trace_hardirqs_off+0x10/0x10 [ 44.490054] ? lock_acquire+0x1d5/0x580 [ 44.494013] ? lock_acquire+0x1d5/0x580 [ 44.497956] ? inet6_csk_xmit+0x114/0x580 [ 44.502071] ? trace_hardirqs_off+0x10/0x10 [ 44.506360] ? lock_release+0xa40/0xa40 [ 44.510309] inet6_csk_xmit+0x2fc/0x580 [ 44.514259] ? inet6_csk_update_pmtu+0x160/0x160 [ 44.518986] ? __sk_dst_check+0x1a5/0x380 [ 44.523106] ? sock_kfree_s+0x60/0x60 [ 44.526884] l2tp_xmit_skb+0x105f/0x1410 [ 44.530917] ? l2tp_session_create+0xb80/0xb80 [ 44.535469] ? sock_wmalloc+0x15d/0x1d0 [ 44.539413] ? iov_iter_advance+0x13f0/0x13f0 [ 44.543876] ? pppol2tp_sendmsg+0x41b/0x670 [ 44.548171] pppol2tp_sendmsg+0x470/0x670 [ 44.552290] ? selinux_socket_sendmsg+0x36/0x40 [ 44.556930] ? pppol2tp_getsockopt+0x900/0x900 [ 44.561479] sock_sendmsg+0xca/0x110 [ 44.565166] SYSC_sendto+0x361/0x5c0 [ 44.568847] ? SYSC_connect+0x4a0/0x4a0 [ 44.572795] ? inet_dgram_connect+0x172/0x1f0 [ 44.577259] ? SYSC_connect+0x2e0/0x4a0 [ 44.581217] ? mm_fault_error+0x2c0/0x2c0 [ 44.585335] ? move_addr_to_kernel+0x60/0x60 [ 44.589714] SyS_sendto+0x40/0x50 [ 44.593134] ? SyS_getpeername+0x30/0x30 [ 44.597169] do_syscall_64+0x281/0x940 [ 44.601025] ? __do_page_fault+0xc90/0xc90 [ 44.605227] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 44.609953] ? syscall_return_slowpath+0x550/0x550 [ 44.614849] ? syscall_return_slowpath+0x2ac/0x550 [ 44.619746] ? prepare_exit_to_usermode+0x350/0x350 [ 44.624732] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 44.630069] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.634882] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.640042] RIP: 0033:0x43ff49 [ 44.643199] RSP: 002b:00007ffde3acb6a8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c [ 44.650878] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 44.658119] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 44.665357] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 44.672596] R10: 0000000000040001 R11: 0000000000000216 R12: 0000000000401870 [ 44.679834] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 44.687491] Dumping ftrace buffer: [ 44.691001] (ftrace buffer empty) [ 44.694690] Kernel Offset: disabled [ 44.698288] Rebooting in 86400 seconds..