[?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. [ 17.655463] audit: type=1400 audit(1520999257.145:6): avc: denied { map } for pid=4184 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 '10.128.10.5' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 24.005268] audit: type=1400 audit(1520999263.495:7): avc: denied { map } for pid=4198 comm="syzkaller419517" path="/root/syzkaller419517738" 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 [ 24.010015] ================================================================== [ 24.038559] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 24.044676] Read of size 8 at addr ffff8801b5574e18 by task syzkaller419517/4198 [ 24.052178] [ 24.053779] CPU: 0 PID: 4198 Comm: syzkaller419517 Not tainted 4.16.0-rc4+ #264 [ 24.061190] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.070511] Call Trace: [ 24.073071] dump_stack+0x194/0x24d [ 24.076671] ? arch_local_irq_restore+0x53/0x53 [ 24.081311] ? show_regs_print_info+0x18/0x18 [ 24.085783] ? ip6_xmit+0x1f76/0x2260 [ 24.089557] print_address_description+0x73/0x250 [ 24.094372] ? ip6_xmit+0x1f76/0x2260 [ 24.098143] kasan_report+0x23c/0x360 [ 24.101917] __asan_report_load8_noabort+0x14/0x20 [ 24.106821] ip6_xmit+0x1f76/0x2260 [ 24.110430] ? ip6_finish_output2+0x23d0/0x23d0 [ 24.115071] ? fl6_update_dst+0x127/0x2b0 [ 24.119194] ? inet6_csk_route_socket+0x691/0xe80 [ 24.124013] ? trace_hardirqs_off+0x10/0x10 [ 24.128314] ? lock_acquire+0x1d5/0x580 [ 24.132257] ? lock_acquire+0x1d5/0x580 [ 24.136199] ? inet6_csk_xmit+0x114/0x580 [ 24.140320] ? trace_hardirqs_off+0x10/0x10 [ 24.144617] ? lock_release+0xa40/0xa40 [ 24.148577] inet6_csk_xmit+0x2fc/0x580 [ 24.152524] ? inet6_csk_update_pmtu+0x160/0x160 [ 24.157250] ? __sk_dst_check+0x1a5/0x380 [ 24.161373] ? sock_kzfree_s+0x60/0x60 [ 24.165245] l2tp_xmit_skb+0x105f/0x1410 [ 24.169287] ? l2tp_session_create+0xb80/0xb80 [ 24.173841] ? sock_wmalloc+0x15d/0x1d0 [ 24.177786] ? iov_iter_advance+0x13f0/0x13f0 [ 24.182259] ? pppol2tp_sendmsg+0x41b/0x670 [ 24.186555] pppol2tp_sendmsg+0x470/0x670 [ 24.190677] ? selinux_socket_sendmsg+0x36/0x40 [ 24.195316] ? pppol2tp_getsockopt+0x900/0x900 [ 24.199871] sock_sendmsg+0xca/0x110 [ 24.203645] SYSC_sendto+0x361/0x5c0 [ 24.207333] ? SYSC_connect+0x4a0/0x4a0 [ 24.211290] ? inet_dgram_connect+0x172/0x1f0 [ 24.215758] ? SYSC_connect+0x2e0/0x4a0 [ 24.219730] ? mm_fault_error+0x2c0/0x2c0 [ 24.223848] ? move_addr_to_kernel+0x60/0x60 [ 24.228229] SyS_sendto+0x40/0x50 [ 24.231653] ? SyS_getpeername+0x30/0x30 [ 24.235685] do_syscall_64+0x281/0x940 [ 24.239543] ? __do_page_fault+0xc90/0xc90 [ 24.243748] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 24.248474] ? syscall_return_slowpath+0x550/0x550 [ 24.253373] ? syscall_return_slowpath+0x2ac/0x550 [ 24.258272] ? prepare_exit_to_usermode+0x350/0x350 [ 24.263259] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 24.268599] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.273420] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.278578] RIP: 0033:0x43ff49 [ 24.281737] RSP: 002b:00007fff081d5c18 EFLAGS: 00000216 ORIG_RAX: 000000000000002c [ 24.289413] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 24.296661] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 24.303902] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 24.311144] R10: 0000000000040001 R11: 0000000000000216 R12: 0000000000401870 [ 24.318384] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 24.325646] [ 24.327250] Allocated by task 3863: [ 24.330846] save_stack+0x43/0xd0 [ 24.334265] kasan_kmalloc+0xad/0xe0 [ 24.337948] kasan_slab_alloc+0x12/0x20 [ 24.341895] kmem_cache_alloc+0x12e/0x760 [ 24.346021] dst_alloc+0x11f/0x1a0 [ 24.349535] rt_dst_alloc+0xe9/0x4e0 [ 24.353218] ip_route_input_slow+0x1284/0x3c80 [ 24.357771] ip_route_input_rcu+0xf1/0xd20 [ 24.361984] ip_route_input_noref+0xf5/0x1e0 [ 24.366360] ip_rcv_finish+0x3a6/0x2040 [ 24.370302] ip_rcv+0xb76/0x1820 [ 24.373638] __netif_receive_skb_core+0x1a41/0x3460 [ 24.378631] __netif_receive_skb+0x2c/0x1b0 [ 24.382921] netif_receive_skb_internal+0x10b/0x670 [ 24.387906] napi_gro_receive+0x3d0/0x500 [ 24.392029] receive_buf+0xb6f/0x2530 [ 24.395799] virtnet_poll+0x320/0xb70 [ 24.399570] net_rx_action+0x792/0x1910 [ 24.403512] __do_softirq+0x2d7/0xb85 [ 24.407278] [ 24.408876] Freed by task 3894: [ 24.412125] save_stack+0x43/0xd0 [ 24.415545] __kasan_slab_free+0x11a/0x170 [ 24.419750] kasan_slab_free+0xe/0x10 [ 24.423519] kmem_cache_free+0x83/0x2a0 [ 24.427471] dst_destroy+0x257/0x370 [ 24.431152] dst_destroy_rcu+0x16/0x20 [ 24.435013] rcu_process_callbacks+0xd6c/0x17f0 [ 24.439655] __do_softirq+0x2d7/0xb85 [ 24.443421] [ 24.445022] The buggy address belongs to the object at ffff8801b5574e00 [ 24.445022] which belongs to the cache ip_dst_cache of size 160 [ 24.457735] The buggy address is located 24 bytes inside of [ 24.457735] 160-byte region [ffff8801b5574e00, ffff8801b5574ea0) [ 24.469487] The buggy address belongs to the page: [ 24.474384] page:ffffea0006d55d00 count:1 mapcount:0 mapping:ffff8801b5574000 index:0xffff8801b5574000 [ 24.483799] flags: 0x2fffc0000000100(slab) [ 24.488002] raw: 02fffc0000000100 ffff8801b5574000 ffff8801b5574000 000000010000000a [ 24.495858] raw: ffffea0006edf320 ffff8801d5b8df38 ffff8801d5b854c0 0000000000000000 [ 24.503713] page dumped because: kasan: bad access detected [ 24.509387] [ 24.510984] Memory state around the buggy address: [ 24.515883] ffff8801b5574d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 24.523212] ffff8801b5574d80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 24.530539] >ffff8801b5574e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 24.537866] ^ [ 24.541985] ffff8801b5574e80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc [ 24.549311] ffff8801b5574f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 24.556635] ================================================================== [ 24.563960] Disabling lock debugging due to kernel taint [ 24.569419] Kernel panic - not syncing: panic_on_warn set ... [ 24.569419] [ 24.576766] CPU: 0 PID: 4198 Comm: syzkaller419517 Tainted: G B 4.16.0-rc4+ #264 [ 24.585480] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.594803] Call Trace: [ 24.597359] dump_stack+0x194/0x24d [ 24.600956] ? arch_local_irq_restore+0x53/0x53 [ 24.605590] ? kasan_end_report+0x32/0x50 [ 24.609707] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 24.614432] ? vsnprintf+0x1ed/0x1900 [ 24.618200] ? ip6_xmit+0x1f40/0x2260 [ 24.621970] panic+0x1e4/0x41c [ 24.625130] ? refcount_error_report+0x214/0x214 [ 24.629858] ? add_taint+0x1c/0x50 [ 24.633366] ? add_taint+0x1c/0x50 [ 24.636874] ? ip6_xmit+0x1f76/0x2260 [ 24.640641] kasan_end_report+0x50/0x50 [ 24.644582] kasan_report+0x149/0x360 [ 24.648356] __asan_report_load8_noabort+0x14/0x20 [ 24.653254] ip6_xmit+0x1f76/0x2260 [ 24.656855] ? ip6_finish_output2+0x23d0/0x23d0 [ 24.661492] ? fl6_update_dst+0x127/0x2b0 [ 24.665609] ? inet6_csk_route_socket+0x691/0xe80 [ 24.670421] ? trace_hardirqs_off+0x10/0x10 [ 24.674710] ? lock_acquire+0x1d5/0x580 [ 24.678654] ? lock_acquire+0x1d5/0x580 [ 24.682593] ? inet6_csk_xmit+0x114/0x580 [ 24.686713] ? trace_hardirqs_off+0x10/0x10 [ 24.691004] ? lock_release+0xa40/0xa40 [ 24.694962] inet6_csk_xmit+0x2fc/0x580 [ 24.698906] ? inet6_csk_update_pmtu+0x160/0x160 [ 24.703629] ? __sk_dst_check+0x1a5/0x380 [ 24.707750] ? sock_kzfree_s+0x60/0x60 [ 24.711616] l2tp_xmit_skb+0x105f/0x1410 [ 24.715650] ? l2tp_session_create+0xb80/0xb80 [ 24.720200] ? sock_wmalloc+0x15d/0x1d0 [ 24.724143] ? iov_iter_advance+0x13f0/0x13f0 [ 24.728607] ? pppol2tp_sendmsg+0x41b/0x670 [ 24.732898] pppol2tp_sendmsg+0x470/0x670 [ 24.737020] ? selinux_socket_sendmsg+0x36/0x40 [ 24.741659] ? pppol2tp_getsockopt+0x900/0x900 [ 24.746213] sock_sendmsg+0xca/0x110 [ 24.749896] SYSC_sendto+0x361/0x5c0 [ 24.753580] ? SYSC_connect+0x4a0/0x4a0 [ 24.757531] ? inet_dgram_connect+0x172/0x1f0 [ 24.761997] ? SYSC_connect+0x2e0/0x4a0 [ 24.765962] ? mm_fault_error+0x2c0/0x2c0 [ 24.770079] ? move_addr_to_kernel+0x60/0x60 [ 24.774460] SyS_sendto+0x40/0x50 [ 24.777888] ? SyS_getpeername+0x30/0x30 [ 24.781920] do_syscall_64+0x281/0x940 [ 24.785776] ? __do_page_fault+0xc90/0xc90 [ 24.789982] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 24.794717] ? syscall_return_slowpath+0x550/0x550 [ 24.799622] ? syscall_return_slowpath+0x2ac/0x550 [ 24.804521] ? prepare_exit_to_usermode+0x350/0x350 [ 24.809506] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 24.814838] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.819650] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.824807] RIP: 0033:0x43ff49 [ 24.827968] RSP: 002b:00007fff081d5c18 EFLAGS: 00000216 ORIG_RAX: 000000000000002c [ 24.835642] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 24.842890] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 24.850131] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 24.857372] R10: 0000000000040001 R11: 0000000000000216 R12: 0000000000401870 [ 24.864609] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 24.872309] Dumping ftrace buffer: [ 24.875826] (ftrace buffer empty) [ 24.879506] Kernel Offset: disabled [ 24.883105] Rebooting in 86400 seconds..