syzbot

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BUG: KMSAN: uninit-value in load_unaligned_zeropad arch/x86/include/asm/word-at-a-time.h:84 [inline]
BUG: KMSAN: uninit-value in __siphash_aligned+0x512/0xae0 lib/siphash.c:67
CPU: 0 PID: 7908 Comm: syz-executor3 Not tainted 4.20.0-rc7+ #8
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x120/0x290 mm/kmsan/kmsan.c:611
 kmsan_internal_check_memory+0x9a7/0xa20 mm/kmsan/kmsan.c:702
 __msan_instrument_asm_load+0x8a/0x90 mm/kmsan/kmsan_instr.c:67
 load_unaligned_zeropad arch/x86/include/asm/word-at-a-time.h:84 [inline]
 __siphash_aligned+0x512/0xae0 lib/siphash.c:67
 ___siphash_aligned include/linux/siphash.h:68 [inline]
 siphash include/linux/siphash.h:84 [inline]
 secure_ipv6_port_ephemeral+0x110/0x220 net/core/secure_seq.c:110
 inet6_sk_port_offset net/ipv6/inet6_hashtables.c:317 [inline]
 inet6_hash_connect+0x11f/0x1a0 net/ipv6/inet6_hashtables.c:328
 tcp_v6_connect+0x20ba/0x2890 net/ipv6/tcp_ipv6.c:299
 __inet_stream_connect+0x2f9/0x1340 net/ipv4/af_inet.c:655
 tcp_sendmsg_fastopen net/ipv4/tcp.c:1161 [inline]
 tcp_sendmsg_locked+0x65d5/0x6be0 net/ipv4/tcp.c:1208
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1443
 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457669
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:00007f1a583d3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457669
RDX: 000000000000feef RSI: 0000000020000440 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000020000040 R09: 000000000000001c
R10: 0000000020000007 R11: 0000000000000246 R12: 00007f1a583d46d4
R13: 00000000004c4539 R14: 00000000004d75a8 R15: 00000000ffffffff

Local variable description: ----combined@secure_ipv6_port_ephemeral
Variable was created at:
 secure_ipv6_port_ephemeral+0x6a/0x220 net/core/secure_seq.c:99
 inet6_sk_port_offset net/ipv6/inet6_hashtables.c:317 [inline]
 inet6_hash_connect+0x11f/0x1a0 net/ipv6/inet6_hashtables.c:328

Bytes 2-7 of 8 are uninitialized
Memory access of size 8 starts at ffff88814e44f5f0
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