audit: type=1400 audit(1519569041.215:6): avc: denied { map } for pid=4144 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 audit: type=1400 audit(1519569047.459:7): avc: denied { map } for pid=4158 comm="syzkaller145980" path="/root/syzkaller145980823" 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 ================================================================== BUG: KASAN: use-after-free in sock_net_uid include/net/sock.h:1733 [inline] BUG: KASAN: use-after-free in ip6_route_me_harder+0x9d8/0xc00 net/ipv6/netfilter.c:26 Read of size 4 at addr ffff8801be6b51b0 by task syzkaller145980/4158 CPU: 1 PID: 4158 Comm: syzkaller145980 Not tainted 4.16.0-rc2+ #241 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report+0x23b/0x360 mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 sock_net_uid include/net/sock.h:1733 [inline] ip6_route_me_harder+0x9d8/0xc00 net/ipv6/netfilter.c:26 ip6t_mangle_out net/ipv6/netfilter/ip6table_mangle.c:63 [inline] ip6table_mangle_hook+0x636/0x920 net/ipv6/netfilter/ip6table_mangle.c:77 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] NF_HOOK include/linux/netfilter.h:286 [inline] ip6_xmit+0x10ec/0x2260 net/ipv6/ip6_output.c:277 tcp_v6_send_synack+0x57b/0xaa0 net/ipv6/tcp_ipv6.c:490 tcp_conn_request+0x26fd/0x3660 net/ipv4/tcp_input.c:6335 tcp_v6_conn_request+0x212/0x270 net/ipv6/tcp_ipv6.c:1021 tcp_rcv_state_process+0x92a/0x4760 net/ipv4/tcp_input.c:5842 tcp_v6_do_rcv+0x739/0x1250 net/ipv6/tcp_ipv6.c:1331 tcp_v6_rcv+0x25a0/0x2d40 net/ipv6/tcp_ipv6.c:1521 ip6_input_finish+0x37e/0x17a0 net/ipv6/ip6_input.c:284 NF_HOOK include/linux/netfilter.h:288 [inline] ip6_input+0xdb/0x560 net/ipv6/ip6_input.c:327 dst_input include/net/dst.h:449 [inline] ip6_rcv_finish+0x297/0x8c0 net/ipv6/ip6_input.c:71 NF_HOOK include/linux/netfilter.h:288 [inline] ipv6_rcv+0xf37/0x1fa0 net/ipv6/ip6_input.c:208 __netif_receive_skb_core+0x1a41/0x3460 net/core/dev.c:4554 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4619 process_backlog+0x203/0x740 net/core/dev.c:5299 napi_poll net/core/dev.c:5697 [inline] net_rx_action+0x792/0x1910 net/core/dev.c:5763 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1011 do_softirq.part.19+0x14d/0x190 kernel/softirq.c:329 do_softirq kernel/softirq.c:177 [inline] __local_bh_enable_ip+0x1ee/0x230 kernel/softirq.c:182 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:726 [inline] ip6_finish_output2+0xba0/0x23a0 net/ipv6/ip6_output.c:121 ip6_finish_output+0x69b/0xaf0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip6_output+0x1eb/0x840 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:288 [inline] ip6_xmit+0xe1f/0x2260 net/ipv6/ip6_output.c:277 inet6_csk_xmit+0x2fc/0x580 net/ipv6/inet6_connection_sock.c:139 tcp_transmit_skb+0x1b12/0x3960 net/ipv4/tcp_output.c:1176 tcp_send_syn_data net/ipv4/tcp_output.c:3459 [inline] tcp_connect+0x1f45/0x40f0 net/ipv4/tcp_output.c:3498 tcp_v6_connect+0x2083/0x26c0 net/ipv6/tcp_ipv6.c:306 __inet_stream_connect+0x2d4/0xf00 net/ipv4/af_inet.c:620 tcp_sendmsg_fastopen net/ipv4/tcp.c:1152 [inline] tcp_sendmsg_locked+0x25ca/0x3960 net/ipv4/tcp.c:1198 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1436 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xca/0x110 net/socket.c:639 SYSC_sendto+0x361/0x5c0 net/socket.c:1748 SyS_sendto+0x40/0x50 net/socket.c:1716 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x44c9b9 RSP: 002b:00007ffd3f7c97a8 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ffd3f7c9890 RCX: 000000000044c9b9 RDX: 0000000000000000 RSI: 00000000204e8000 RDI: 0000000000000004 RBP: 0000000000000000 R08: 000000002007f000 R09: 000000000000001c R10: 0000000020000001 R11: 0000000000000216 R12: 000000000040e280 R13: 000000000040e310 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 4156: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3541 dup_mmap kernel/fork.c:451 [inline] dup_mm kernel/fork.c:1233 [inline] copy_mm+0x8d7/0x131f kernel/fork.c:1287 copy_process.part.38+0x1f56/0x4b60 kernel/fork.c:1793 copy_process kernel/fork.c:1606 [inline] _do_fork+0x1f7/0xf70 kernel/fork.c:2087 SYSC_clone kernel/fork.c:2194 [inline] SyS_clone+0x37/0x50 kernel/fork.c:2188 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 4158: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527 __cache_free mm/slab.c:3485 [inline] kmem_cache_free+0x83/0x2a0 mm/slab.c:3743 remove_vma+0x162/0x1b0 mm/mmap.c:176 exit_mmap+0x311/0x500 mm/mmap.c:3049 __mmput kernel/fork.c:960 [inline] mmput+0x223/0x6d0 kernel/fork.c:981 exec_mmap fs/exec.c:1039 [inline] flush_old_exec+0xc8b/0x2010 fs/exec.c:1271 load_elf_binary+0x87b/0x4c10 fs/binfmt_elf.c:864 search_binary_handler+0x142/0x6b0 fs/exec.c:1638 exec_binprm fs/exec.c:1680 [inline] do_execveat_common.isra.30+0x1754/0x23c0 fs/exec.c:1802 do_execve fs/exec.c:1847 [inline] SYSC_execve fs/exec.c:1928 [inline] SyS_execve+0x39/0x50 fs/exec.c:1923 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff8801be6b5148 which belongs to the cache vm_area_struct of size 200 The buggy address is located 104 bytes inside of 200-byte region [ffff8801be6b5148, ffff8801be6b5210) The buggy address belongs to the page: page:ffffea0006f9ad40 count:1 mapcount:0 mapping:ffff8801be6b5040 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801be6b5040 0000000000000000 000000010000000f raw: ffffea0006c4ed20 ffffea0006f97de0 ffff8801da5c3840 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801be6b5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801be6b5100: fb fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb >ffff8801be6b5180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801be6b5200: fb fb fc fc fc fc fc fc fc fc fb fb fb fb fb fb ffff8801be6b5280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================