raw_sendmsg: syz-executor5 forgot to set AF_INET. Fix it! ================================================================== BUG: KMSAN: uninit-value in __ipv6_prefix_equal64_half include/net/ipv6.h:535 [inline] BUG: KMSAN: uninit-value in ipv6_prefix_equal include/net/ipv6.h:552 [inline] BUG: KMSAN: uninit-value in check_6rd+0x65a/0x710 net/ipv6/sit.c:771 CPU: 1 PID: 22558 Comm: syz-executor4 Not tainted 4.20.0-rc5+ #2 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+0x1c9/0x220 lib/dump_stack.c:113 kmsan_report+0x12d/0x290 mm/kmsan/kmsan.c:682 __msan_warning+0x76/0xc0 mm/kmsan/kmsan_instr.c:316 __ipv6_prefix_equal64_half include/net/ipv6.h:535 [inline] ipv6_prefix_equal include/net/ipv6.h:552 [inline] check_6rd+0x65a/0x710 net/ipv6/sit.c:771 try_6rd net/ipv6/sit.c:805 [inline] ipip6_tunnel_xmit net/ipv6/sit.c:865 [inline] sit_tunnel_xmit+0xb58/0x34d0 net/ipv6/sit.c:1029 __netdev_start_xmit include/linux/netdevice.h:4356 [inline] netdev_start_xmit include/linux/netdevice.h:4365 [inline] xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0x627/0xc80 net/core/dev.c:3268 __dev_queue_xmit+0x3173/0x3cf0 net/core/dev.c:3838 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3871 packet_snd net/packet/af_packet.c:2928 [inline] packet_sendmsg+0x7cbd/0x9200 net/packet/af_packet.c:2953 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] sock_write_iter+0x3f4/0x4f0 net/socket.c:900 call_write_iter include/linux/fs.h:1857 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x888/0xb80 fs/read_write.c:487 vfs_write+0x4b4/0x900 fs/read_write.c:549 ksys_write fs/read_write.c:598 [inline] __do_sys_write fs/read_write.c:610 [inline] __se_sys_write+0x17a/0x370 fs/read_write.c:607 __x64_sys_write+0x4a/0x70 fs/read_write.c:607 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x457679 Code: fd b3 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 b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f320a3ffc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457679 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f320a4006d4 R13: 00000000004c607f R14: 00000000004dac00 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:247 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:170 kmsan_kmalloc+0xa1/0x100 mm/kmsan/kmsan_hooks.c:179 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:188 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2759 [inline] __kmalloc_node_track_caller+0xf06/0x1120 mm/slub.c:4383 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x318/0xa40 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:998 [inline] alloc_skb_with_frags+0x1c9/0xa80 net/core/skbuff.c:5220 sock_alloc_send_pskb+0xb5d/0x1140 net/core/sock.c:2083 packet_alloc_skb net/packet/af_packet.c:2781 [inline] packet_snd net/packet/af_packet.c:2872 [inline] packet_sendmsg+0x66a2/0x9200 net/packet/af_packet.c:2953 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] sock_write_iter+0x3f4/0x4f0 net/socket.c:900 call_write_iter include/linux/fs.h:1857 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x888/0xb80 fs/read_write.c:487 vfs_write+0x4b4/0x900 fs/read_write.c:549 ksys_write fs/read_write.c:598 [inline] __do_sys_write fs/read_write.c:610 [inline] __se_sys_write+0x17a/0x370 fs/read_write.c:607 __x64_sys_write+0x4a/0x70 fs/read_write.c:607 do_syscall_64+0xcd/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================