================================================================== BUG: KMSAN: uninit-value in __ipv6_prefix_equal64_half include/net/ipv6.h:515 [inline] BUG: KMSAN: uninit-value in ipv6_prefix_equal include/net/ipv6.h:532 [inline] BUG: KMSAN: uninit-value in check_6rd net/ipv6/sit.c:771 [inline] BUG: KMSAN: uninit-value in try_6rd net/ipv6/sit.c:805 [inline] BUG: KMSAN: uninit-value in ipip6_tunnel_xmit net/ipv6/sit.c:865 [inline] BUG: KMSAN: uninit-value in sit_tunnel_xmit+0x18c0/0x3640 net/ipv6/sit.c:1029 CPU: 1 PID: 11035 Comm: syz-executor2 Not tainted 4.18.0-rc8+ #34 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+0x17c/0x1c0 lib/dump_stack.c:113 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:982 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645 __ipv6_prefix_equal64_half include/net/ipv6.h:515 [inline] ipv6_prefix_equal include/net/ipv6.h:532 [inline] check_6rd net/ipv6/sit.c:771 [inline] try_6rd net/ipv6/sit.c:805 [inline] ipip6_tunnel_xmit net/ipv6/sit.c:865 [inline] sit_tunnel_xmit+0x18c0/0x3640 net/ipv6/sit.c:1029 __netdev_start_xmit include/linux/netdevice.h:4148 [inline] netdev_start_xmit include/linux/netdevice.h:4157 [inline] xmit_one net/core/dev.c:3034 [inline] dev_hard_start_xmit+0x5df/0xc20 net/core/dev.c:3050 __dev_queue_xmit+0x2eea/0x3a70 net/core/dev.c:3569 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3602 packet_snd net/packet/af_packet.c:2921 [inline] packet_sendmsg+0x7fb5/0x8ae0 net/packet/af_packet.c:2946 sock_sendmsg_nosec net/socket.c:642 [inline] sock_sendmsg net/socket.c:652 [inline] ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126 __sys_sendmsg net/socket.c:2164 [inline] __do_sys_sendmsg net/socket.c:2173 [inline] __se_sys_sendmsg net/socket.c:2171 [inline] __x64_sys_sendmsg+0x32d/0x460 net/socket.c:2171 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457089 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7313e2ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7313e2b6d4 RCX: 0000000000457089 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d3ff8 R14: 00000000004c8a56 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2720 [inline] __kmalloc_node_track_caller+0xb4c/0x11d0 mm/slub.c:4353 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2ce/0x9b0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:988 [inline] alloc_skb_with_frags+0x1d0/0xac0 net/core/skbuff.c:5272 sock_alloc_send_pskb+0xb47/0x1120 net/core/sock.c:2095 packet_alloc_skb net/packet/af_packet.c:2776 [inline] packet_snd net/packet/af_packet.c:2867 [inline] packet_sendmsg+0x6480/0x8ae0 net/packet/af_packet.c:2946 sock_sendmsg_nosec net/socket.c:642 [inline] sock_sendmsg net/socket.c:652 [inline] ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126 __sys_sendmsg net/socket.c:2164 [inline] __do_sys_sendmsg net/socket.c:2173 [inline] __se_sys_sendmsg net/socket.c:2171 [inline] __x64_sys_sendmsg+0x32d/0x460 net/socket.c:2171 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================