[....] Starting enhanced syslogd: rsyslogd[ 15.432352] audit: type=1400 audit(1520963125.097:5): avc: denied { syslog } for pid=3933 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: [ 18.792639] audit: type=1400 audit(1520963128.457:6): avc: denied { map } for pid=4072 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 '10.128.10.21' (ECDSA) to the list of known hosts. executing program [ 36.632455] audit: type=1400 audit(1520963146.297:7): avc: denied { map } for pid=4090 comm="syzkaller748893" path="/root/syzkaller748893515" 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 [ 36.636684] ================================================================== [ 36.666393] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 36.672511] Read of size 8 at addr ffff8801b7d76e18 by task syzkaller748893/4090 [ 36.680012] [ 36.681614] CPU: 0 PID: 4090 Comm: syzkaller748893 Not tainted 4.16.0-rc5+ #352 [ 36.689034] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.698359] Call Trace: [ 36.700926] dump_stack+0x194/0x24d [ 36.704526] ? arch_local_irq_restore+0x53/0x53 [ 36.709166] ? show_regs_print_info+0x18/0x18 [ 36.713644] ? ip6_xmit+0x1f76/0x2260 [ 36.717421] print_address_description+0x73/0x250 [ 36.722236] ? ip6_xmit+0x1f76/0x2260 [ 36.726010] kasan_report+0x23c/0x360 [ 36.729798] __asan_report_load8_noabort+0x14/0x20 [ 36.734699] ip6_xmit+0x1f76/0x2260 [ 36.738308] ? ip6_finish_output2+0x23a0/0x23a0 [ 36.742950] ? fl6_update_dst+0x127/0x2b0 [ 36.747072] ? inet6_csk_route_socket+0x691/0xe80 [ 36.751891] ? trace_hardirqs_off+0x10/0x10 [ 36.756185] ? lock_acquire+0x1d5/0x580 [ 36.760129] ? lock_acquire+0x1d5/0x580 [ 36.764072] ? inet6_csk_xmit+0x114/0x580 [ 36.768191] ? trace_hardirqs_off+0x10/0x10 [ 36.772484] ? lock_release+0xa40/0xa40 [ 36.776443] inet6_csk_xmit+0x2fc/0x580 [ 36.780388] ? inet6_csk_update_pmtu+0x160/0x160 [ 36.785113] ? __sk_dst_check+0x1a5/0x380 [ 36.789243] ? sock_kfree_s+0x60/0x60 [ 36.793029] l2tp_xmit_skb+0x105f/0x1410 [ 36.797071] ? l2tp_session_create+0xb80/0xb80 [ 36.801626] ? sock_wmalloc+0x15d/0x1d0 [ 36.805574] ? iov_iter_advance+0x13f0/0x13f0 [ 36.810046] ? pppol2tp_sendmsg+0x41b/0x670 [ 36.814340] pppol2tp_sendmsg+0x470/0x670 [ 36.818468] ? selinux_socket_sendmsg+0x36/0x40 [ 36.823110] ? pppol2tp_getsockopt+0x900/0x900 [ 36.827663] sock_sendmsg+0xca/0x110 [ 36.831350] SYSC_sendto+0x361/0x5c0 [ 36.835038] ? SYSC_connect+0x4a0/0x4a0 [ 36.838995] ? inet_dgram_connect+0x172/0x1f0 [ 36.843462] ? SYSC_connect+0x2e0/0x4a0 [ 36.847437] ? mm_fault_error+0x2c0/0x2c0 [ 36.851557] ? move_addr_to_kernel+0x60/0x60 [ 36.855939] SyS_sendto+0x40/0x50 [ 36.859362] ? SyS_getpeername+0x30/0x30 [ 36.863395] do_syscall_64+0x281/0x940 [ 36.867252] ? __do_page_fault+0xc90/0xc90 [ 36.871457] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 36.876190] ? syscall_return_slowpath+0x550/0x550 [ 36.881098] ? syscall_return_slowpath+0x2ac/0x550 [ 36.886001] ? prepare_exit_to_usermode+0x350/0x350 [ 36.890995] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 36.896334] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.901153] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 36.906313] RIP: 0033:0x43ff99 [ 36.909474] RSP: 002b:00007ffe28139328 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 36.917150] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff99 [ 36.924398] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 36.931638] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 36.938879] R10: 0000000000040001 R11: 0000000000000212 R12: 00000000004018c0 [ 36.946118] R13: 0000000000401950 R14: 0000000000000000 R15: 0000000000000000 [ 36.953373] [ 36.954971] Allocated by task 2068: [ 36.958580] save_stack+0x43/0xd0 [ 36.962013] kasan_kmalloc+0xad/0xe0 [ 36.965695] kasan_slab_alloc+0x12/0x20 [ 36.969638] kmem_cache_alloc+0x12e/0x760 [ 36.973755] dst_alloc+0x11f/0x1a0 [ 36.977274] rt_dst_alloc+0xe9/0x520 [ 36.980956] ip_route_input_rcu+0x1076/0x3200 [ 36.985420] ip_route_input_noref+0xf5/0x1e0 [ 36.989796] ip_rcv_finish+0x3a6/0x2040 [ 36.993739] ip_rcv+0xb76/0x1820 [ 36.997075] __netif_receive_skb_core+0x1a41/0x3460 [ 37.002068] __netif_receive_skb+0x2c/0x1b0 [ 37.006359] netif_receive_skb_internal+0x10b/0x670 [ 37.011345] napi_gro_receive+0x3d0/0x500 [ 37.015460] receive_buf+0xb6f/0x2530 [ 37.019229] virtnet_poll+0x320/0xb70 [ 37.022996] net_rx_action+0x792/0x1910 [ 37.026944] __do_softirq+0x2d7/0xb85 [ 37.030711] [ 37.032310] Freed by task 0: [ 37.035297] save_stack+0x43/0xd0 [ 37.038724] __kasan_slab_free+0x11a/0x170 [ 37.042926] kasan_slab_free+0xe/0x10 [ 37.046694] kmem_cache_free+0x83/0x2a0 [ 37.050636] dst_destroy+0x257/0x370 [ 37.054321] dst_destroy_rcu+0x16/0x20 [ 37.058181] rcu_process_callbacks+0xd6c/0x17f0 [ 37.062828] __do_softirq+0x2d7/0xb85 [ 37.066598] [ 37.068197] The buggy address belongs to the object at ffff8801b7d76e00 [ 37.068197] which belongs to the cache ip_dst_cache of size 168 [ 37.080913] The buggy address is located 24 bytes inside of [ 37.080913] 168-byte region [ffff8801b7d76e00, ffff8801b7d76ea8) [ 37.092667] The buggy address belongs to the page: [ 37.097565] page:ffffea0006df5d80 count:1 mapcount:0 mapping:ffff8801b7d76000 index:0xffff8801b7d76900 [ 37.106988] flags: 0x2fffc0000000100(slab) [ 37.111196] raw: 02fffc0000000100 ffff8801b7d76000 ffff8801b7d76900 000000010000000f [ 37.119047] raw: ffff8801d5bafe38 ffffea00074d9160 ffff8801d6bc4040 0000000000000000 [ 37.126897] page dumped because: kasan: bad access detected [ 37.132576] [ 37.134171] Memory state around the buggy address: [ 37.139078] ffff8801b7d76d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.146407] ffff8801b7d76d80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 37.153734] >ffff8801b7d76e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.161061] ^ [ 37.165180] ffff8801b7d76e80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc [ 37.172507] ffff8801b7d76f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.179841] ================================================================== [ 37.187173] Disabling lock debugging due to kernel taint [ 37.192638] Kernel panic - not syncing: panic_on_warn set ... [ 37.192638] [ 37.199976] CPU: 0 PID: 4090 Comm: syzkaller748893 Tainted: G B 4.16.0-rc5+ #352 [ 37.208696] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.218019] Call Trace: [ 37.220584] dump_stack+0x194/0x24d [ 37.224185] ? arch_local_irq_restore+0x53/0x53 [ 37.228821] ? kasan_end_report+0x32/0x50 [ 37.232942] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.237666] ? vsnprintf+0x1ed/0x1900 [ 37.241444] ? ip6_xmit+0x1f30/0x2260 [ 37.245213] panic+0x1e4/0x41c [ 37.248375] ? refcount_error_report+0x214/0x214 [ 37.253101] ? add_taint+0x1c/0x50 [ 37.256611] ? add_taint+0x1c/0x50 [ 37.260120] ? ip6_xmit+0x1f76/0x2260 [ 37.263890] kasan_end_report+0x50/0x50 [ 37.267833] kasan_report+0x149/0x360 [ 37.271606] __asan_report_load8_noabort+0x14/0x20 [ 37.276502] ip6_xmit+0x1f76/0x2260 [ 37.280103] ? ip6_finish_output2+0x23a0/0x23a0 [ 37.284741] ? fl6_update_dst+0x127/0x2b0 [ 37.288860] ? inet6_csk_route_socket+0x691/0xe80 [ 37.293683] ? trace_hardirqs_off+0x10/0x10 [ 37.297972] ? lock_acquire+0x1d5/0x580 [ 37.301914] ? lock_acquire+0x1d5/0x580 [ 37.305863] ? inet6_csk_xmit+0x114/0x580 [ 37.309978] ? trace_hardirqs_off+0x10/0x10 [ 37.314271] ? lock_release+0xa40/0xa40 [ 37.318223] inet6_csk_xmit+0x2fc/0x580 [ 37.322167] ? inet6_csk_update_pmtu+0x160/0x160 [ 37.326890] ? __sk_dst_check+0x1a5/0x380 [ 37.331006] ? sock_kfree_s+0x60/0x60 [ 37.334783] l2tp_xmit_skb+0x105f/0x1410 [ 37.338824] ? l2tp_session_create+0xb80/0xb80 [ 37.343378] ? sock_wmalloc+0x15d/0x1d0 [ 37.347320] ? iov_iter_advance+0x13f0/0x13f0 [ 37.351786] ? pppol2tp_sendmsg+0x41b/0x670 [ 37.356081] pppol2tp_sendmsg+0x470/0x670 [ 37.360200] ? selinux_socket_sendmsg+0x36/0x40 [ 37.364847] ? pppol2tp_getsockopt+0x900/0x900 [ 37.369397] sock_sendmsg+0xca/0x110 [ 37.373078] SYSC_sendto+0x361/0x5c0 [ 37.376759] ? SYSC_connect+0x4a0/0x4a0 [ 37.380710] ? inet_dgram_connect+0x172/0x1f0 [ 37.385182] ? SYSC_connect+0x2e0/0x4a0 [ 37.389142] ? mm_fault_error+0x2c0/0x2c0 [ 37.393261] ? move_addr_to_kernel+0x60/0x60 [ 37.397639] SyS_sendto+0x40/0x50 [ 37.401060] ? SyS_getpeername+0x30/0x30 [ 37.405095] do_syscall_64+0x281/0x940 [ 37.408948] ? __do_page_fault+0xc90/0xc90 [ 37.413152] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.417876] ? syscall_return_slowpath+0x550/0x550 [ 37.422774] ? syscall_return_slowpath+0x2ac/0x550 [ 37.427680] ? prepare_exit_to_usermode+0x350/0x350 [ 37.432669] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 37.438001] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.442815] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 37.447979] RIP: 0033:0x43ff99 [ 37.451136] RSP: 002b:00007ffe28139328 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 37.458810] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff99 [ 37.466048] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 37.473287] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 37.480526] R10: 0000000000040001 R11: 0000000000000212 R12: 00000000004018c0 [ 37.487764] R13: 0000000000401950 R14: 0000000000000000 R15: 0000000000000000 [ 37.495453] Dumping ftrace buffer: [ 37.498961] (ftrace buffer empty) [ 37.502643] Kernel Offset: disabled [ 37.506247] Rebooting in 86400 seconds..