[....] Starting enhanced syslogd: rsyslogd[ 15.151294] audit: type=1400 audit(1520779978.743:5): avc: denied { syslog } for pid=4070 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: [ 19.314352] audit: type=1400 audit(1520779982.906:6): 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 '10.128.10.8' (ECDSA) to the list of known hosts. executing program [ 31.035467] audit: type=1400 audit(1520779994.627:7): avc: denied { map } for pid=4226 comm="syzkaller697693" path="/root/syzkaller697693567" 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 [ 31.040587] ================================================================== [ 31.068748] BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 [ 31.074861] Read of size 8 at addr ffff8801cae88c18 by task syzkaller697693/4226 [ 31.082361] [ 31.083963] CPU: 0 PID: 4226 Comm: syzkaller697693 Not tainted 4.16.0-rc4+ #260 [ 31.091376] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.100698] Call Trace: [ 31.103260] dump_stack+0x194/0x24d [ 31.106861] ? arch_local_irq_restore+0x53/0x53 [ 31.111838] ? show_regs_print_info+0x18/0x18 [ 31.116314] ? ip6_xmit+0x1f76/0x2260 [ 31.120090] print_address_description+0x73/0x250 [ 31.124905] ? ip6_xmit+0x1f76/0x2260 [ 31.128677] kasan_report+0x23c/0x360 [ 31.132454] __asan_report_load8_noabort+0x14/0x20 [ 31.137355] ip6_xmit+0x1f76/0x2260 [ 31.140963] ? ip6_finish_output2+0x23d0/0x23d0 [ 31.145607] ? fl6_update_dst+0x127/0x2b0 [ 31.149738] ? inet6_csk_route_socket+0x691/0xe80 [ 31.154558] ? trace_hardirqs_off+0x10/0x10 [ 31.158853] ? lock_acquire+0x1d5/0x580 [ 31.162796] ? lock_acquire+0x1d5/0x580 [ 31.166739] ? inet6_csk_xmit+0x114/0x580 [ 31.170858] ? trace_hardirqs_off+0x10/0x10 [ 31.175152] ? lock_release+0xa40/0xa40 [ 31.179113] inet6_csk_xmit+0x2fc/0x580 [ 31.183060] ? inet6_csk_update_pmtu+0x160/0x160 [ 31.187788] ? __sk_dst_check+0x1a5/0x380 [ 31.191914] ? sock_kzfree_s+0x60/0x60 [ 31.195790] l2tp_xmit_skb+0x105f/0x1410 [ 31.199831] ? l2tp_session_create+0xb80/0xb80 [ 31.204386] ? sock_wmalloc+0x15d/0x1d0 [ 31.208332] ? iov_iter_advance+0x13f0/0x13f0 [ 31.212801] ? pppol2tp_sendmsg+0x41b/0x670 [ 31.217095] pppol2tp_sendmsg+0x470/0x670 [ 31.221216] ? selinux_socket_sendmsg+0x36/0x40 [ 31.225859] ? pppol2tp_getsockopt+0x900/0x900 [ 31.230413] sock_sendmsg+0xca/0x110 [ 31.234099] SYSC_sendto+0x361/0x5c0 [ 31.237789] ? SYSC_connect+0x4a0/0x4a0 [ 31.241743] ? inet_dgram_connect+0x172/0x1f0 [ 31.246212] ? SYSC_connect+0x2e0/0x4a0 [ 31.250188] ? mm_fault_error+0x2c0/0x2c0 [ 31.254308] ? move_addr_to_kernel+0x60/0x60 [ 31.258693] SyS_sendto+0x40/0x50 [ 31.262120] ? SyS_getpeername+0x30/0x30 [ 31.266155] do_syscall_64+0x281/0x940 [ 31.270020] ? __do_page_fault+0xc90/0xc90 [ 31.274235] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 31.279745] ? syscall_return_slowpath+0x550/0x550 [ 31.284647] ? syscall_return_slowpath+0x2ac/0x550 [ 31.289550] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 31.294888] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.299708] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.304868] RIP: 0033:0x43ff49 [ 31.308035] RSP: 002b:00007ffe73168158 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 31.315716] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 31.322957] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 31.330196] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 31.337436] R10: 0000000000040001 R11: 0000000000000212 R12: 0000000000401870 [ 31.344689] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 31.351942] [ 31.353544] Allocated by task 4209: [ 31.357149] save_stack+0x43/0xd0 [ 31.360570] kasan_kmalloc+0xad/0xe0 [ 31.364251] kasan_slab_alloc+0x12/0x20 [ 31.368199] kmem_cache_alloc+0x12e/0x760 [ 31.372319] dst_alloc+0x11f/0x1a0 [ 31.375828] rt_dst_alloc+0xe9/0x4e0 [ 31.379515] ip_route_output_key_hash_rcu+0xa59/0x2fe0 [ 31.384782] ip_route_output_key_hash+0x20b/0x370 [ 31.389608] __ip4_datagram_connect+0xa67/0x1240 [ 31.394337] __ip6_datagram_connect+0x749/0x12d0 [ 31.399064] ip6_datagram_connect+0x2f/0x50 [ 31.403355] inet_dgram_connect+0x16b/0x1f0 [ 31.407646] SYSC_connect+0x213/0x4a0 [ 31.411417] SyS_connect+0x24/0x30 [ 31.414931] do_syscall_64+0x281/0x940 [ 31.418789] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.423946] [ 31.425544] Freed by task 0: [ 31.428535] save_stack+0x43/0xd0 [ 31.431957] __kasan_slab_free+0x11a/0x170 [ 31.436162] kasan_slab_free+0xe/0x10 [ 31.439936] kmem_cache_free+0x83/0x2a0 [ 31.443882] dst_destroy+0x257/0x370 [ 31.447574] dst_destroy_rcu+0x16/0x20 [ 31.451442] rcu_process_callbacks+0xd6c/0x17f0 [ 31.456082] __do_softirq+0x2d7/0xb85 [ 31.459848] [ 31.461451] The buggy address belongs to the object at ffff8801cae88c00 [ 31.461451] which belongs to the cache ip_dst_cache of size 160 [ 31.474161] The buggy address is located 24 bytes inside of [ 31.474161] 160-byte region [ffff8801cae88c00, ffff8801cae88ca0) [ 31.485914] The buggy address belongs to the page: [ 31.490812] page:ffffea00072ba200 count:1 mapcount:0 mapping:ffff8801cae88000 index:0x0 [ 31.498925] flags: 0x2fffc0000000100(slab) [ 31.503132] raw: 02fffc0000000100 ffff8801cae88000 0000000000000000 0000000100000010 [ 31.510980] raw: ffff8801d6bc2548 ffff8801d6bc2548 ffff8801d540ec80 0000000000000000 [ 31.518826] page dumped because: kasan: bad access detected [ 31.524512] [ 31.526121] Memory state around the buggy address: [ 31.531019] ffff8801cae88b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.538348] ffff8801cae88b80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 31.545677] >ffff8801cae88c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.553002] ^ [ 31.557118] ffff8801cae88c80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc [ 31.564446] ffff8801cae88d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.571771] ================================================================== [ 31.579096] Disabling lock debugging due to kernel taint [ 31.584546] Kernel panic - not syncing: panic_on_warn set ... [ 31.584546] [ 31.591876] CPU: 0 PID: 4226 Comm: syzkaller697693 Tainted: G B 4.16.0-rc4+ #260 [ 31.600589] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.609910] Call Trace: [ 31.612470] dump_stack+0x194/0x24d [ 31.616068] ? arch_local_irq_restore+0x53/0x53 [ 31.620705] ? kasan_end_report+0x32/0x50 [ 31.624822] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.629549] ? vsnprintf+0x1ed/0x1900 [ 31.633320] ? ip6_xmit+0x1eb0/0x2260 [ 31.637091] panic+0x1e4/0x41c [ 31.640254] ? refcount_error_report+0x214/0x214 [ 31.644980] ? add_taint+0x1c/0x50 [ 31.648486] ? add_taint+0x1c/0x50 [ 31.651997] ? ip6_xmit+0x1f76/0x2260 [ 31.655764] kasan_end_report+0x50/0x50 [ 31.659709] kasan_report+0x149/0x360 [ 31.663480] __asan_report_load8_noabort+0x14/0x20 [ 31.668378] ip6_xmit+0x1f76/0x2260 [ 31.671981] ? ip6_finish_output2+0x23d0/0x23d0 [ 31.676619] ? fl6_update_dst+0x127/0x2b0 [ 31.680735] ? inet6_csk_route_socket+0x691/0xe80 [ 31.685548] ? trace_hardirqs_off+0x10/0x10 [ 31.689835] ? lock_acquire+0x1d5/0x580 [ 31.693775] ? lock_acquire+0x1d5/0x580 [ 31.697717] ? inet6_csk_xmit+0x114/0x580 [ 31.701831] ? trace_hardirqs_off+0x10/0x10 [ 31.706122] ? lock_release+0xa40/0xa40 [ 31.710070] inet6_csk_xmit+0x2fc/0x580 [ 31.714012] ? inet6_csk_update_pmtu+0x160/0x160 [ 31.718738] ? __sk_dst_check+0x1a5/0x380 [ 31.722853] ? sock_kzfree_s+0x60/0x60 [ 31.726715] l2tp_xmit_skb+0x105f/0x1410 [ 31.730750] ? l2tp_session_create+0xb80/0xb80 [ 31.735298] ? sock_wmalloc+0x15d/0x1d0 [ 31.739243] ? iov_iter_advance+0x13f0/0x13f0 [ 31.743710] ? pppol2tp_sendmsg+0x41b/0x670 [ 31.748002] pppol2tp_sendmsg+0x470/0x670 [ 31.752120] ? selinux_socket_sendmsg+0x36/0x40 [ 31.756756] ? pppol2tp_getsockopt+0x900/0x900 [ 31.761309] sock_sendmsg+0xca/0x110 [ 31.764994] SYSC_sendto+0x361/0x5c0 [ 31.768676] ? SYSC_connect+0x4a0/0x4a0 [ 31.772624] ? inet_dgram_connect+0x172/0x1f0 [ 31.777087] ? SYSC_connect+0x2e0/0x4a0 [ 31.781046] ? mm_fault_error+0x2c0/0x2c0 [ 31.785160] ? move_addr_to_kernel+0x60/0x60 [ 31.789536] SyS_sendto+0x40/0x50 [ 31.792957] ? SyS_getpeername+0x30/0x30 [ 31.796987] do_syscall_64+0x281/0x940 [ 31.800839] ? __do_page_fault+0xc90/0xc90 [ 31.805042] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 31.810548] ? syscall_return_slowpath+0x550/0x550 [ 31.815464] ? syscall_return_slowpath+0x2ac/0x550 [ 31.820366] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 31.825696] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.830511] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.835665] RIP: 0033:0x43ff49 [ 31.838821] RSP: 002b:00007ffe73168158 EFLAGS: 00000212 ORIG_RAX: 000000000000002c [ 31.846495] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff49 [ 31.853730] RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004 [ 31.860967] RBP: 00000000006ca018 R08: 00000000200021c0 R09: 0000000000000080 [ 31.868205] R10: 0000000000040001 R11: 0000000000000212 R12: 0000000000401870 [ 31.875445] R13: 0000000000401900 R14: 0000000000000000 R15: 0000000000000000 [ 31.883116] Dumping ftrace buffer: [ 31.886640] (ftrace buffer empty) [ 31.890321] Kernel Offset: disabled [ 31.893916] Rebooting in 86400 seconds..