syzbot

IPVS: ftp: loaded support on port[0] = 21
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BUG: KASAN: slab-out-of-bounds in __xfrm6_tunnel_spi_lookup+0x3a9/0x3b0 net/ipv6/xfrm6_tunnel.c:79
Read of size 8 at addr ffff888094e43628 by task syz-executor155/6833
CPU: 1 PID: 6833 Comm: syz-executor155 Not tainted 5.8.0-rc5-next-20200714-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 __xfrm6_tunnel_spi_lookup+0x3a9/0x3b0 net/ipv6/xfrm6_tunnel.c:79
 xfrm6_tunnel_spi_lookup+0x8a/0x1d0 net/ipv6/xfrm6_tunnel.c:95
 xfrmi6_rcv_tunnel+0xb9/0x100 net/xfrm/xfrm_interface.c:810
 tunnel46_rcv+0xef/0x2b0 net/ipv6/tunnel6.c:193
 ip6_protocol_deliver_rcu+0x2e8/0x1670 net/ipv6/ip6_input.c:433
 ip6_input_finish+0x7f/0x160 net/ipv6/ip6_input.c:474
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:483
 dst_input include/net/dst.h:449 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x28e/0x3c0 net/ipv6/ip6_input.c:307
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5287
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5401
 netif_receive_skb_internal net/core/dev.c:5503 [inline]
 netif_receive_skb+0x159/0x990 net/core/dev.c:5562
 tun_rx_batched.isra.0+0x460/0x720 drivers/net/tun.c:1518
 tun_get_user+0x23b2/0x35b0 drivers/net/tun.c:1972
 tun_chr_write_iter+0xba/0x151 drivers/net/tun.c:2001
 call_write_iter include/linux/fs.h:1879 [inline]
 new_sync_write+0x422/0x650 fs/read_write.c:515
 vfs_write+0x59d/0x6b0 fs/read_write.c:595
 ksys_write+0x12d/0x250 fs/read_write.c:648
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x401650
Code: Bad RIP value.
RSP: 002b:00007fffa8ce24f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fffa8ce2500 RCX: 0000000000401650
RDX: 000000000000004a RSI: 0000000020000340 RDI: 00000000000000f0
RBP: 00007fffa8ce2510 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fffa8ce2508 R14: 0000000000000000 R15: 0000000000000000
Allocated by task 6833:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 kmalloc_node include/linux/slab.h:577 [inline]
 kvmalloc_node+0x61/0xf0 mm/util.c:574
 kvmalloc include/linux/mm.h:760 [inline]
 kvzalloc include/linux/mm.h:768 [inline]
 netif_alloc_netdev_queues net/core/dev.c:9378 [inline]
 alloc_netdev_mqs+0x6eb/0xdc0 net/core/dev.c:9993
 ip6gre_init_net+0x1e3/0x610 net/ipv6/ip6_gre.c:1569
 ops_init+0xaf/0x470 net/core/net_namespace.c:151
 setup_net+0x2d8/0x850 net/core/net_namespace.c:341
 copy_net_ns+0x2cf/0x5e0 net/core/net_namespace.c:482
 create_new_namespaces+0x3f6/0xb10 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:231
 ksys_unshare+0x445/0x8e0 kernel/fork.c:2927
 __do_sys_unshare kernel/fork.c:2995 [inline]
 __se_sys_unshare kernel/fork.c:2993 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2993
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
The buggy address belongs to the object at ffff888094e43400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 40 bytes to the right of
 512-byte region [ffff888094e43400, ffff888094e43600)
The buggy address belongs to the page:
page:000000001d3e0bbb refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x94e43
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea000289b448 ffffea00028d4b48 ffff8880aa000600
raw: 0000000000000000 ffff888094e43000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
 ffff888094e43500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888094e43580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888094e43600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff888094e43680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888094e43700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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