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BUG: KMSAN: uninit-value in virtio_net_hdr_to_skb+0x1414/0x14f0 include/linux/virtio_net.h:86
CPU: 0 PID: 16638 Comm: syz-executor.0 Not tainted 5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 virtio_net_hdr_to_skb+0x1414/0x14f0 include/linux/virtio_net.h:86
 packet_snd net/packet/af_packet.c:2994 [inline]
 packet_sendmsg+0x85b8/0x99d0 net/packet/af_packet.c:3031
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 sock_write_iter+0x585/0x680 net/socket.c:1001
 call_write_iter include/linux/fs.h:1977 [inline]
 aio_write+0x833/0xad0 fs/aio.c:1581
 __io_submit_one fs/aio.c:1840 [inline]
 io_submit_one+0x1d1a/0x4230 fs/aio.c:1883
 __do_sys_io_submit fs/aio.c:1942 [inline]
 __se_sys_io_submit+0x35b/0x7a0 fs/aio.c:1912
 __x64_sys_io_submit+0x4a/0x70 fs/aio.c:1912
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1f3c234188 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9
RDX: 0000000020000080 RSI: 0000000000000001 RDI: 00007f1f3c235000
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 0000000000a9fb1f R14: 00007f1f3c234300 R15: 0000000000022000

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:120
 kmsan_alloc_page+0xd0/0x1e0 mm/kmsan/kmsan_shadow.c:273
 __alloc_pages_nodemask+0x827/0xf90 mm/page_alloc.c:5044
 alloc_pages_current+0x7b6/0xb60 mm/mempolicy.c:2277
 alloc_pages include/linux/gfp.h:561 [inline]
 alloc_slab_page mm/slub.c:1653 [inline]
 allocate_slab+0x364/0x1260 mm/slub.c:1793
 new_slab mm/slub.c:1856 [inline]
 new_slab_objects mm/slub.c:2602 [inline]
 ___slab_alloc+0xd42/0x1930 mm/slub.c:2765
 __slab_alloc mm/slub.c:2805 [inline]
 slab_alloc_node mm/slub.c:2886 [inline]
 slab_alloc mm/slub.c:2931 [inline]
 kmem_cache_alloc+0xc68/0x1030 mm/slub.c:2936
 sk_prot_alloc+0xef/0x5a0 net/core/sock.c:1697
 sk_alloc+0xe7/0xe90 net/core/sock.c:1756
 inet6_create+0x8ed/0x1880 net/ipv6/af_inet6.c:183
 __sock_create+0xa00/0x1040 net/socket.c:1408
 sock_create_kern+0xf0/0x100 net/socket.c:1477
 udp_sock_create6+0x113/0xc00 net/ipv6/ip6_udp_tunnel.c:23
 udp_sock_create include/net/udp_tunnel.h:62 [inline]
 geneve_create_sock drivers/net/geneve.c:460 [inline]
 geneve_socket_create drivers/net/geneve.c:575 [inline]
 geneve_sock_add+0x86a/0x1500 drivers/net/geneve.c:662
 geneve_open+0x156/0x340 drivers/net/geneve.c:698
 __dev_open+0x900/0xb90 net/core/dev.c:1563
 __dev_change_flags+0x3fd/0xcd0 net/core/dev.c:8686
 dev_change_flags+0xf5/0x280 net/core/dev.c:8757
 do_setlink+0x17f6/0x7890 net/core/rtnetlink.c:2708
 __rtnl_newlink net/core/rtnetlink.c:3376 [inline]
 rtnl_newlink+0x2fc4/0x3d80 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x143b/0x18e0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x6fa/0x810 net/netlink/af_netlink.c:2502
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x11d6/0x14a0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x1740/0x1840 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 __sys_sendto+0x9ea/0xc60 net/socket.c:1977
 __do_sys_sendto net/socket.c:1989 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1985
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1985
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xae
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