==================================================================
BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2705 [inline]
BUG: KMSAN: uninit-value in __kmalloc_node_track_caller+0x667/0x11d0 mm/slub.c:4353
CPU: 1 PID: 8162 Comm: syz-executor7 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
 slab_alloc_node mm/slub.c:2705 [inline]
 __kmalloc_node_track_caller+0x667/0x11d0 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
 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2112
 __ip6_append_data+0x3a80/0x50e0 net/ipv6/ip6_output.c:1422
 ip6_make_skb+0x6de/0xcd0 net/ipv6/ip6_output.c:1778
 udpv6_sendmsg+0x3e04/0x43c0 net/ipv6/udp.c:1376
 inet_sendmsg+0x49a/0x740 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126
 __sys_sendmmsg+0x4ac/0x930 net/socket.c:2221
 __do_sys_sendmmsg net/socket.c:2250 [inline]
 __se_sys_sendmmsg net/socket.c:2247 [inline]
 __x64_sys_sendmmsg+0x11c/0x170 net/socket.c:2247
 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:00007f11f45ebc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f11f45ec6d4 RCX: 0000000000457089
RDX: 00000000000004ff RSI: 00000000200092c0 RDI: 0000000000000003
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d3d98 R14: 00000000004c87ed R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:271 [inline]
 kmsan_internal_chain_origin+0x128/0x210 mm/kmsan/kmsan.c:573
 kmsan_memcpy_origins+0x13d/0x1b0 mm/kmsan/kmsan.c:397
 __msan_memcpy+0xda/0x130 mm/kmsan/kmsan_instr.c:432
 pskb_expand_head+0x3b3/0x19b0 net/core/skbuff.c:1472
 skb_unclone include/linux/skbuff.h:1443 [inline]
 __tcp_retransmit_skb+0xb13/0x3bd0 net/ipv4/tcp_output.c:2865
 tcp_send_loss_probe+0x823/0xad0 net/ipv4/tcp_output.c:2519
 tcp_write_timer_handler+0x730/0xee0 net/ipv4/tcp_timer.c:569
 tcp_write_timer+0x11e/0x270 net/ipv4/tcp_timer.c:593
 call_timer_fn+0x270/0x5c0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd74/0x1170 kernel/time/timer.c:1666
 run_timer_softirq+0x43/0x70 kernel/time/timer.c:1692
 __do_softirq+0x582/0x969 kernel/softirq.c:292

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_fclone include/linux/skbuff.h:1030 [inline]
 sk_stream_alloc_skb+0x172/0xc90 net/ipv4/tcp.c:875
 tcp_sendmsg_locked+0x2a4d/0x6250 net/ipv4/tcp.c:1290
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1447
 inet_sendmsg+0x49a/0x740 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 sock_write_iter+0x3b8/0x470 net/socket.c:921
 call_write_iter include/linux/fs.h:1793 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x7ac/0xa50 fs/read_write.c:487
 vfs_write+0x467/0x8c0 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 fs/read_write.c:607 [inline]
 __x64_sys_write+0x1b7/0x3c0 fs/read_write.c:607
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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