================================================================== BUG: KASAN: slab-out-of-bounds in __ipv6_addr_type+0x26c/0x290 net/ipv6/addrconf_core.c:68 Read of size 4 at addr ffff8800b48f9db8 by task syz-executor.1/18097 CPU: 1 PID: 18097 Comm: syz-executor.1 Not tainted 4.4.174+ #4 0000000000000000 7637920860d7b1f2 ffff8801cfd76da0 ffffffff81aad1a1 0000000000000000 ffffea0002d23e00 ffff8800b48f9db8 0000000000000004 ffff8800b48f9b00 ffff8801cfd76dd8 ffffffff81490120 0000000000000000 Call Trace: [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<ffffffff81490120>] print_address_description+0x6f/0x21b mm/kasan/report.c:252 [<ffffffff81490358>] kasan_report_error mm/kasan/report.c:351 [inline] [<ffffffff81490358>] kasan_report mm/kasan/report.c:408 [inline] [<ffffffff81490358>] kasan_report.cold+0x8c/0x2be mm/kasan/report.c:393 [<ffffffff81484eb4>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428 [<ffffffff826bbd4c>] __ipv6_addr_type+0x26c/0x290 net/ipv6/addrconf_core.c:68 [<ffffffff826b141c>] ipv6_addr_type include/net/ipv6.h:330 [inline] [<ffffffff826b141c>] ip6_tnl_xmit2+0x2ac/0x2320 net/ipv6/ip6_tunnel.c:988 [<ffffffff826b4e59>] ip4ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1134 [inline] [<ffffffff826b4e59>] ip6_tnl_xmit+0xa09/0xe00 net/ipv6/ip6_tunnel.c:1212 [<ffffffff82245071>] __netdev_start_xmit include/linux/netdevice.h:3750 [inline] [<ffffffff82245071>] netdev_start_xmit include/linux/netdevice.h:3759 [inline] [<ffffffff82245071>] xmit_one net/core/dev.c:2781 [inline] [<ffffffff82245071>] dev_hard_start_xmit+0x7c1/0x11e0 net/core/dev.c:2797 [<ffffffff822473cb>] __dev_queue_xmit+0x164b/0x1bb0 net/core/dev.c:3229 [<ffffffff82247948>] dev_queue_xmit+0x18/0x20 net/core/dev.c:3263 [<ffffffff8225c136>] neigh_direct_output+0x16/0x20 net/core/neighbour.c:1369 [<ffffffff823c5412>] dst_neigh_output include/net/dst.h:461 [inline] [<ffffffff823c5412>] ip_finish_output2+0x6a2/0x1280 net/ipv4/ip_output.c:213 [<ffffffff823cc6e2>] ip_finish_output+0x8b2/0xc60 net/ipv4/ip_output.c:288 [<ffffffff823d04a7>] NF_HOOK_COND include/linux/netfilter.h:240 [inline] [<ffffffff823d04a7>] ip_output+0x227/0x4c0 net/ipv4/ip_output.c:362 [<ffffffff823cd21c>] dst_output include/net/dst.h:498 [inline] [<ffffffff823cd21c>] ip_local_out+0x9c/0x180 net/ipv4/ip_output.c:119 [<ffffffff823d300e>] ip_send_skb+0x3e/0xc0 net/ipv4/ip_output.c:1453 [<ffffffff82478ded>] udp_send_skb+0x4fd/0xc70 net/ipv4/udp.c:842 [<ffffffff8247fb9f>] udp_sendmsg+0x16cf/0x1c60 net/ipv4/udp.c:1072 [<ffffffff826137a2>] udpv6_sendmsg+0x12f2/0x24f0 net/ipv6/udp.c:1173 [<ffffffff824a8b42>] inet_sendmsg+0x202/0x4d0 net/ipv4/af_inet.c:755 [<ffffffff821d838e>] sock_sendmsg_nosec net/socket.c:638 [inline] [<ffffffff821d838e>] sock_sendmsg+0xbe/0x110 net/socket.c:648 [<ffffffff821da269>] ___sys_sendmsg+0x769/0x890 net/socket.c:1975 [<ffffffff821dd0c5>] __sys_sendmsg+0xc5/0x160 net/socket.c:2009 [<ffffffff821dd18d>] SYSC_sendmsg net/socket.c:2020 [inline] [<ffffffff821dd18d>] SyS_sendmsg+0x2d/0x50 net/socket.c:2016 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a Allocated by task 18097: [<ffffffff8102e3c6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [<ffffffff81483f22>] save_stack mm/kasan/kasan.c:512 [inline] [<ffffffff81483f22>] set_track mm/kasan/kasan.c:524 [inline] [<ffffffff81483f22>] kasan_kmalloc.part.0+0x62/0xf0 mm/kasan/kasan.c:616 [<ffffffff81484197>] kasan_kmalloc+0xb7/0xd0 mm/kasan/kasan.c:601 [<ffffffff81480521>] __kmalloc+0x141/0x330 mm/slub.c:3613 [<ffffffff82264216>] kmalloc include/linux/slab.h:481 [inline] [<ffffffff82264216>] kzalloc include/linux/slab.h:620 [inline] [<ffffffff82264216>] neigh_alloc net/core/neighbour.c:285 [inline] [<ffffffff82264216>] __neigh_create+0x1d6/0x1b30 net/core/neighbour.c:457 [<ffffffff823a024e>] neigh_create include/net/neighbour.h:313 [inline] [<ffffffff823a024e>] ipv4_neigh_lookup+0x52e/0x6e0 net/ipv4/route.c:464 [<ffffffff826b13eb>] dst_neigh_lookup include/net/dst.h:466 [inline] [<ffffffff826b13eb>] ip6_tnl_xmit2+0x27b/0x2320 net/ipv6/ip6_tunnel.c:982 [<ffffffff826b4e59>] ip4ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1134 [inline] [<ffffffff826b4e59>] ip6_tnl_xmit+0xa09/0xe00 net/ipv6/ip6_tunnel.c:1212 [<ffffffff82245071>] __netdev_start_xmit include/linux/netdevice.h:3750 [inline] [<ffffffff82245071>] netdev_start_xmit include/linux/netdevice.h:3759 [inline] [<ffffffff82245071>] xmit_one net/core/dev.c:2781 [inline] [<ffffffff82245071>] dev_hard_start_xmit+0x7c1/0x11e0 net/core/dev.c:2797 [<ffffffff822473cb>] __dev_queue_xmit+0x164b/0x1bb0 net/core/dev.c:3229 [<ffffffff82247948>] dev_queue_xmit+0x18/0x20 net/core/dev.c:3263 [<ffffffff8225c136>] neigh_direct_output+0x16/0x20 net/core/neighbour.c:1369 [<ffffffff823c5412>] dst_neigh_output include/net/dst.h:461 [inline] [<ffffffff823c5412>] ip_finish_output2+0x6a2/0x1280 net/ipv4/ip_output.c:213 [<ffffffff823cc6e2>] ip_finish_output+0x8b2/0xc60 net/ipv4/ip_output.c:288 [<ffffffff823d04a7>] NF_HOOK_COND include/linux/netfilter.h:240 [inline] [<ffffffff823d04a7>] ip_output+0x227/0x4c0 net/ipv4/ip_output.c:362 [<ffffffff823cd21c>] dst_output include/net/dst.h:498 [inline] [<ffffffff823cd21c>] ip_local_out+0x9c/0x180 net/ipv4/ip_output.c:119 [<ffffffff823d300e>] ip_send_skb+0x3e/0xc0 net/ipv4/ip_output.c:1453 [<ffffffff82478ded>] udp_send_skb+0x4fd/0xc70 net/ipv4/udp.c:842 [<ffffffff8247fb9f>] udp_sendmsg+0x16cf/0x1c60 net/ipv4/udp.c:1072 [<ffffffff826137a2>] udpv6_sendmsg+0x12f2/0x24f0 net/ipv6/udp.c:1173 [<ffffffff824a8b42>] inet_sendmsg+0x202/0x4d0 net/ipv4/af_inet.c:755 [<ffffffff821d838e>] sock_sendmsg_nosec net/socket.c:638 [inline] [<ffffffff821d838e>] sock_sendmsg+0xbe/0x110 net/socket.c:648 [<ffffffff821da269>] ___sys_sendmsg+0x769/0x890 net/socket.c:1975 [<ffffffff821dd0c5>] __sys_sendmsg+0xc5/0x160 net/socket.c:2009 [<ffffffff821dd18d>] SYSC_sendmsg net/socket.c:2020 [inline] [<ffffffff821dd18d>] SyS_sendmsg+0x2d/0x50 net/socket.c:2016 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a Freed by task 15659: [<ffffffff8102e3c6>] save_stack_trace+0x26/0x50 arch/x86/kernel/stacktrace.c:63 [<ffffffff81484820>] save_stack mm/kasan/kasan.c:512 [inline] [<ffffffff81484820>] set_track mm/kasan/kasan.c:524 [inline] [<ffffffff81484820>] kasan_slab_free+0xb0/0x190 mm/kasan/kasan.c:589 [<ffffffff81481c44>] slab_free_hook mm/slub.c:1383 [inline] [<ffffffff81481c44>] slab_free_freelist_hook mm/slub.c:1405 [inline] [<ffffffff81481c44>] slab_free mm/slub.c:2859 [inline] [<ffffffff81481c44>] kfree+0xf4/0x310 mm/slub.c:3749 [<ffffffff821fd036>] skb_free_head net/core/skbuff.c:571 [inline] [<ffffffff821fd036>] skb_release_data+0x2e6/0x380 net/core/skbuff.c:602 [<ffffffff821fd11d>] skb_release_all+0x4d/0x60 net/core/skbuff.c:661 [<ffffffff821fd146>] __kfree_skb+0x16/0x30 net/core/skbuff.c:675 [<ffffffff82422d19>] tcp_rcv_established+0x819/0x2070 net/ipv4/tcp_input.c:5434 [<ffffffff8264b3f4>] tcp_v6_do_rcv+0xdb4/0x11d0 net/ipv6/tcp_ipv6.c:1267 [<ffffffff8264dcfe>] tcp_v6_rcv+0x24ee/0x30b0 net/ipv6/tcp_ipv6.c:1477 [<ffffffff825b3c1d>] ip6_input_finish+0x57d/0x14f0 net/ipv6/ip6_input.c:248 [<ffffffff825b66a8>] NF_HOOK_THRESH include/linux/netfilter.h:226 [inline] [<ffffffff825b66a8>] NF_HOOK include/linux/netfilter.h:249 [inline] [<ffffffff825b66a8>] ip6_input+0xf8/0x1f0 net/ipv6/ip6_input.c:280 [<ffffffff825b317d>] dst_input include/net/dst.h:504 [inline] [<ffffffff825b317d>] ip6_rcv_finish+0x14d/0x670 net/ipv6/ip6_input.c:62 [<ffffffff825b5b51>] NF_HOOK_THRESH include/linux/netfilter.h:226 [inline] [<ffffffff825b5b51>] NF_HOOK include/linux/netfilter.h:249 [inline] [<ffffffff825b5b51>] ipv6_rcv+0xfc1/0x1a20 net/ipv6/ip6_input.c:186 [<ffffffff82230640>] __netif_receive_skb_core+0x1300/0x2950 net/core/dev.c:4041 [<ffffffff82238bd8>] __netif_receive_skb+0x58/0x1c0 net/core/dev.c:4076 [<ffffffff8223fec0>] process_backlog+0x200/0x630 net/core/dev.c:4673 [<ffffffff8223f2f7>] napi_poll net/core/dev.c:4911 [inline] [<ffffffff8223f2f7>] net_rx_action+0x367/0xd30 net/core/dev.c:4976 [<ffffffff8271bb16>] __do_softirq+0x226/0xa3f kernel/softirq.c:273 The buggy address belongs to the object at ffff8800b48f9b00 which belongs to the cache kmalloc-1024 of size 1024 The buggy address is located 696 bytes inside of 1024-byte region [ffff8800b48f9b00, ffff8800b48f9f00) The buggy address belongs to the page: kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access[ 1425.702331] ------------[ cut here ]------------ WARNING: CPU: 0 PID: 2126 at kernel/sched/core.c:7941 __might_sleep+0x138/0x1a0 kernel/sched/core.c:7941() do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff810de6f5>] do_wait+0x265/0xa00 kernel/exit.c:1511