================================================================== 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 ffff888097ce1fc8 by task syz-executor.2/9071 CPU: 1 PID: 9071 Comm: syz-executor.2 Not tainted 5.8.0-rc5-next-20200716-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:824 tunnel6_rcv+0xef/0x2b0 net/ipv6/tunnel6.c:148 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 ip6_mc_input+0x411/0xea0 net/ipv6/ip6_input.c:577 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+0x5c6/0x6f0 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: 0033:0x45cba9 Code: Bad RIP value. RSP: 002b:00007f8be0cafc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000510cc0 RCX: 000000000045cba9 RDX: 0000000000000fca RSI: 0000000020000c40 RDI: 0000000000000007 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000dae R14: 00000000004cffcf R15: 00007f8be0cb06d4 Allocated by task 7062: 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 __do_kmalloc mm/slab.c:3655 [inline] __kmalloc+0x1a8/0x320 mm/slab.c:3664 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:666 [inline] ops_init+0xfb/0x470 net/core/net_namespace.c:141 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 ffff888097ce1c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 456 bytes to the right of 512-byte region [ffff888097ce1c00, ffff888097ce1e00) The buggy address belongs to the page: page:00000000fde57821 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x97ce1 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000266bd08 ffffea0002412988 ffff8880aa000600 raw: 0000000000000000 ffff888097ce1000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888097ce1e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888097ce1f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888097ce1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888097ce2000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888097ce2080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================