[....] Starting enhanced syslogd: rsyslogd[ 15.942332] audit: type=1400 audit(1520850813.723:5): avc: denied { syslog } for pid=4043 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 file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.599904] audit: type=1400 audit(1520850816.380:6): avc: denied { map } for pid=4182 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 '10.128.0.44' (ECDSA) to the list of known hosts. executing program [ 24.951550] audit: type=1400 audit(1520850822.732:7): avc: denied { map } for pid=4196 comm="syzkaller432386" path="/root/syzkaller432386908" 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 [ 24.957041] ================================================================== [ 24.985490] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 24.991609] Read of size 8 at addr ffff8801b5bb8f18 by task syzkaller432386/4196 [ 24.999111] [ 25.000715] CPU: 1 PID: 4196 Comm: syzkaller432386 Not tainted 4.16.0-rc5+ #351 [ 25.008132] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.017457] Call Trace: [ 25.020021] dump_stack+0x194/0x24d [ 25.023625] ? arch_local_irq_restore+0x53/0x53 [ 25.028267] ? show_regs_print_info+0x18/0x18 [ 25.032745] ? ip6_xmit+0x1f76/0x2260 [ 25.036523] print_address_description+0x73/0x250 [ 25.041340] ? ip6_xmit+0x1f76/0x2260 [ 25.045113] kasan_report+0x23c/0x360 [ 25.048889] __asan_report_load8_noabort+0x14/0x20 [ 25.053795] ip6_xmit+0x1f76/0x2260 [ 25.057406] ? ip6_finish_output2+0x23a0/0x23a0 [ 25.062052] ? fl6_update_dst+0x127/0x2b0 [ 25.066175] ? inet6_csk_route_socket+0x691/0xe80 [ 25.070997] ? trace_hardirqs_off+0x10/0x10 [ 25.075296] ? lock_acquire+0x1d5/0x580 [ 25.079242] ? lock_acquire+0x1d5/0x580 [ 25.083201] ? inet6_csk_xmit+0x114/0x580 [ 25.087332] ? trace_hardirqs_off+0x10/0x10 [ 25.091630] ? lock_release+0xa40/0xa40 [ 25.095591] inet6_csk_xmit+0x2fc/0x580 [ 25.099541] ? inet6_csk_update_pmtu+0x160/0x160 [ 25.104275] ? __sk_dst_check+0x1a5/0x380 [ 25.108399] ? sock_kfree_s+0x60/0x60 [ 25.112188] l2tp_xmit_skb+0x105f/0x1410 [ 25.116232] ? l2tp_session_create+0xb80/0xb80 [ 25.120785] ? sock_wmalloc+0x15d/0x1d0 [ 25.124734] ? iov_iter_advance+0x13f0/0x13f0 [ 25.129203] ? pppol2tp_sendmsg+0x41b/0x670 [ 25.133500] pppol2tp_sendmsg+0x470/0x670 [ 25.137624] ? selinux_socket_sendmsg+0x36/0x40 [ 25.142271] ? pppol2tp_getsockopt+0x900/0x900 [ 25.146829] sock_sendmsg+0xca/0x110 [ 25.150518] SYSC_sendto+0x361/0x5c0 [ 25.154209] ? SYSC_connect+0x4a0/0x4a0 [ 25.158169] ? inet_dgram_connect+0x172/0x1f0 [ 25.162638] ? SYSC_connect+0x2e0/0x4a0 [ 25.166618] ? mm_fault_error+0x2c0/0x2c0 [ 25.170740] ? move_addr_to_kernel+0x60/0x60 [ 25.175124] SyS_sendto+0x40/0x50 [ 25.178547] ? SyS_getpeername+0x30/0x30 [ 25.182583] do_syscall_64+0x281/0x940 [ 25.186447] ? __do_page_fault+0xc90/0xc90 [ 25.190654] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.195383] ? syscall_return_slowpath+0x550/0x550 [ 25.200288] ? syscall_return_slowpath+0x2ac/0x550 [ 25.205189] ? prepare_exit_to_usermode+0x350/0x350 [ 25.210184] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 25.215525] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.220347] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 25.225507] RIP: 0033:0x440139 [ 25.228669] RSP: 002b:00007ffdce95c848 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 25.236357] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440139 [ 25.243597] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 25.250838] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 25.258080] R10: 0000000000040001 R11: 0000000000000212 R12: 0000000000401a60 [ 25.265324] R13: 0000000000401af0 R14: 0000000000000000 R15: 0000000000000000 [ 25.272579] [ 25.274182] Allocated by task 2068: [ 25.277784] save_stack+0x43/0xd0 [ 25.281208] kasan_kmalloc+0xad/0xe0 [ 25.284893] kasan_slab_alloc+0x12/0x20 [ 25.288840] kmem_cache_alloc+0x12e/0x760 [ 25.292958] dst_alloc+0x11f/0x1a0 [ 25.296471] rt_dst_alloc+0xe9/0x520 [ 25.300157] ip_route_input_rcu+0x1076/0x3200 [ 25.304621] ip_route_input_noref+0xf5/0x1e0 [ 25.309000] ip_rcv_finish+0x3a6/0x2040 [ 25.312945] ip_rcv+0xb76/0x1820 [ 25.316295] __netif_receive_skb_core+0x1a41/0x3460 [ 25.321282] __netif_receive_skb+0x2c/0x1b0 [ 25.325573] netif_receive_skb_internal+0x10b/0x670 [ 25.330584] napi_gro_receive+0x3d0/0x500 [ 25.334704] receive_buf+0xb6f/0x2530 [ 25.338476] virtnet_poll+0x320/0xb70 [ 25.342256] net_rx_action+0x792/0x1910 [ 25.346205] __do_softirq+0x2d7/0xb85 [ 25.349975] [ 25.351574] Freed by task 3746: [ 25.354826] save_stack+0x43/0xd0 [ 25.358250] __kasan_slab_free+0x11a/0x170 [ 25.362456] kasan_slab_free+0xe/0x10 [ 25.366228] kmem_cache_free+0x83/0x2a0 [ 25.370176] dst_destroy+0x257/0x370 [ 25.373858] dst_destroy_rcu+0x16/0x20 [ 25.377722] rcu_process_callbacks+0xd6c/0x17f0 [ 25.382362] __do_softirq+0x2d7/0xb85 [ 25.386133] [ 25.387733] The buggy address belongs to the object at ffff8801b5bb8f00 [ 25.387733] which belongs to the cache ip_dst_cache of size 168 [ 25.400446] The buggy address is located 24 bytes inside of [ 25.400446] 168-byte region [ffff8801b5bb8f00, ffff8801b5bb8fa8) [ 25.412204] The buggy address belongs to the page: [ 25.417108] page:ffffea0006d6ee00 count:1 mapcount:0 mapping:ffff8801b5bb8000 index:0xffff8801b5bb8000 [ 25.426523] flags: 0x2fffc0000000100(slab) [ 25.430734] raw: 02fffc0000000100 ffff8801b5bb8000 ffff8801b5bb8000 000000010000000b [ 25.438585] raw: ffffea0006c6e360 ffff8801d6bd0438 ffff8801d5be6680 0000000000000000 [ 25.446433] page dumped because: kasan: bad access detected [ 25.452111] [ 25.453710] Memory state around the buggy address: [ 25.458609] ffff8801b5bb8e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 25.465937] ffff8801b5bb8e80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 25.473280] >ffff8801b5bb8f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.480608] ^ [ 25.484727] ffff8801b5bb8f80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc [ 25.492056] ffff8801b5bb9000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.499383] ================================================================== [ 25.506711] Disabling lock debugging due to kernel taint [ 25.512170] Kernel panic - not syncing: panic_on_warn set ... [ 25.512170] [ 25.519516] CPU: 1 PID: 4196 Comm: syzkaller432386 Tainted: G B 4.16.0-rc5+ #351 [ 25.528236] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.537561] Call Trace: [ 25.540125] dump_stack+0x194/0x24d [ 25.543723] ? arch_local_irq_restore+0x53/0x53 [ 25.548362] ? kasan_end_report+0x32/0x50 [ 25.552483] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.557210] ? vsnprintf+0x1ed/0x1900 [ 25.560998] ? ip6_xmit+0x1f30/0x2260 [ 25.564774] panic+0x1e4/0x41c [ 25.567937] ? refcount_error_report+0x214/0x214 [ 25.572664] ? add_taint+0x1c/0x50 [ 25.576174] ? add_taint+0x1c/0x50 [ 25.579686] ? ip6_xmit+0x1f76/0x2260 [ 25.583454] kasan_end_report+0x50/0x50 [ 25.587395] kasan_report+0x149/0x360 [ 25.591169] __asan_report_load8_noabort+0x14/0x20 [ 25.596078] ip6_xmit+0x1f76/0x2260 [ 25.599681] ? ip6_finish_output2+0x23a0/0x23a0 [ 25.604322] ? fl6_update_dst+0x127/0x2b0 [ 25.608442] ? inet6_csk_route_socket+0x691/0xe80 [ 25.613258] ? trace_hardirqs_off+0x10/0x10 [ 25.617551] ? lock_acquire+0x1d5/0x580 [ 25.621492] ? lock_acquire+0x1d5/0x580 [ 25.625436] ? inet6_csk_xmit+0x114/0x580 [ 25.629552] ? trace_hardirqs_off+0x10/0x10 [ 25.633843] ? lock_release+0xa40/0xa40 [ 25.637795] inet6_csk_xmit+0x2fc/0x580 [ 25.641740] ? inet6_csk_update_pmtu+0x160/0x160 [ 25.646466] ? __sk_dst_check+0x1a5/0x380 [ 25.650582] ? sock_kfree_s+0x60/0x60 [ 25.654361] l2tp_xmit_skb+0x105f/0x1410 [ 25.658399] ? l2tp_session_create+0xb80/0xb80 [ 25.662953] ? sock_wmalloc+0x15d/0x1d0 [ 25.666898] ? iov_iter_advance+0x13f0/0x13f0 [ 25.671366] ? pppol2tp_sendmsg+0x41b/0x670 [ 25.675658] pppol2tp_sendmsg+0x470/0x670 [ 25.679777] ? selinux_socket_sendmsg+0x36/0x40 [ 25.684416] ? pppol2tp_getsockopt+0x900/0x900 [ 25.688969] sock_sendmsg+0xca/0x110 [ 25.692653] SYSC_sendto+0x361/0x5c0 [ 25.696337] ? SYSC_connect+0x4a0/0x4a0 [ 25.700288] ? inet_dgram_connect+0x172/0x1f0 [ 25.704753] ? SYSC_connect+0x2e0/0x4a0 [ 25.708713] ? mm_fault_error+0x2c0/0x2c0 [ 25.712841] ? move_addr_to_kernel+0x60/0x60 [ 25.717225] SyS_sendto+0x40/0x50 [ 25.720649] ? SyS_getpeername+0x30/0x30 [ 25.724681] do_syscall_64+0x281/0x940 [ 25.728536] ? __do_page_fault+0xc90/0xc90 [ 25.732742] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.737468] ? syscall_return_slowpath+0x550/0x550 [ 25.742366] ? syscall_return_slowpath+0x2ac/0x550 [ 25.747264] ? prepare_exit_to_usermode+0x350/0x350 [ 25.752250] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 25.757585] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.762400] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 25.767557] RIP: 0033:0x440139 [ 25.770716] RSP: 002b:00007ffdce95c848 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 25.778391] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440139 [ 25.785631] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 25.792869] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 25.800383] R10: 0000000000040001 R11: 0000000000000212 R12: 0000000000401a60 [ 25.807621] R13: 0000000000401af0 R14: 0000000000000000 R15: 0000000000000000 [ 25.815335] Dumping ftrace buffer: [ 25.818844] (ftrace buffer empty) [ 25.822526] Kernel Offset: disabled [ 25.826123] Rebooting in 86400 seconds..