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BUG: KMSAN: uninit-value in prefetch_freepointer mm/slub.c:276 [inline]
BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2713 [inline]
BUG: KMSAN: uninit-value in __kmalloc_node_track_caller+0xe81/0x11d0 mm/slub.c:4353
CPU: 1 PID: 13779 Comm: syz-executor6 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
 prefetch_freepointer mm/slub.c:276 [inline]
 slab_alloc_node mm/slub.c:2713 [inline]
 __kmalloc_node_track_caller+0xe81/0x11d0 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]
 __tcp_send_ack+0x10a/0x830 net/ipv4/tcp_output.c:3597
 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3624
 tcp_send_challenge_ack+0x3df/0x4a0 net/ipv4/tcp_input.c:3462
 tcp_validate_incoming+0x1618/0x2710 net/ipv4/tcp_input.c:5416
 tcp_rcv_state_process+0xf6d/0x6200 net/ipv4/tcp_input.c:6022
 tcp_v6_do_rcv+0xfc6/0x1c90 net/ipv6/tcp_ipv6.c:1351
 sk_backlog_rcv include/net/sock.h:914 [inline]
 __release_sock+0x2ae/0x660 net/core/sock.c:2342
 release_sock+0x99/0x2a0 net/core/sock.c:2851
 inet_wait_for_connect net/ipv4/af_inet.c:588 [inline]
 __inet_stream_connect+0xccf/0x1300 net/ipv4/af_inet.c:680
 tcp_sendmsg_fastopen net/ipv4/tcp.c:1162 [inline]
 tcp_sendmsg_locked+0x5cde/0x6250 net/ipv4/tcp.c:1209
 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]
 __sys_sendto+0x6a3/0x7c0 net/socket.c:1798
 __do_sys_sendto net/socket.c:1810 [inline]
 __se_sys_sendto net/socket.c:1806 [inline]
 __x64_sys_sendto+0x1a1/0x210 net/socket.c:1806
 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:00007f643a2cbc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f643a2cc6d4 RCX: 0000000000457089
RDX: 00000000000002bd RSI: 0000000020e77fff RDI: 0000000000000003
RBP: 00000000009300a0 R08: 00000000208d4fe4 R09: 000000000000001c
R10: 0000000020000008 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d4190 R14: 00000000004c8b54 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]
 __tcp_send_ack+0x10a/0x830 net/ipv4/tcp_output.c:3597
 tcp_send_ack+0x68/0x90 net/ipv4/tcp_output.c:3624
 __tcp_ack_snd_check net/ipv4/tcp_input.c:5159 [inline]
 tcp_rcv_established+0x28b8/0x2af0 net/ipv4/tcp_input.c:5575
 tcp_v4_do_rcv+0x61e/0xcb0 net/ipv4/tcp_ipv4.c:1531
 tcp_v4_rcv+0x6b94/0x70e0 net/ipv4/tcp_ipv4.c:1823
 ip_local_deliver_finish+0x7ee/0xea0 net/ipv4/ip_input.c:215
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip_local_deliver+0x438/0x4d0 net/ipv4/ip_input.c:256
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish+0xa6e/0x1cb0 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip_rcv+0x1211/0x1410 net/ipv4/ip_input.c:492
 __netif_receive_skb_core+0x4511/0x49d0 net/core/dev.c:4628
 __netif_receive_skb net/core/dev.c:4693 [inline]
 netif_receive_skb_internal+0x44f/0x620 net/core/dev.c:4767
 napi_skb_finish net/core/dev.c:5129 [inline]
 napi_gro_receive+0x668/0xb10 net/core/dev.c:5160
 receive_buf+0x4f6c/0x7510 drivers/net/virtio_net.c:1002
 virtnet_receive drivers/net/virtio_net.c:1257 [inline]
 virtnet_poll+0xaed/0x13e0 drivers/net/virtio_net.c:1339
 napi_poll net/core/dev.c:5771 [inline]
 net_rx_action+0x723/0x19d0 net/core/dev.c:5837
 __do_softirq+0x582/0x969 kernel/softirq.c:292
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