=====================================================
BUG: KMSAN: uninit-value in virtio_net_hdr_to_skb+0x1414/0x14f0 include/linux/virtio_net.h:86
CPU: 0 PID: 22540 Comm: syz-executor.2 Tainted: G        W         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]
 kernel_sendmsg+0x22c/0x2f0 net/socket.c:694
 sock_no_sendpage+0x205/0x2b0 net/core/sock.c:2860
 kernel_sendpage+0x47a/0x590 net/socket.c:3631
 sock_sendpage+0x161/0x1a0 net/socket.c:947
 pipe_to_sendpage+0x3e4/0x520 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x5e3/0xff0 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0x1d5/0x2c0 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 do_splice+0x23c3/0x2c10 fs/splice.c:1079
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x8fa/0xb50 fs/splice.c:1332
 __ia32_sys_splice+0x6e/0x90 fs/splice.c:1332
 do_syscall_32_irqs_on arch/x86/entry/common.c:79 [inline]
 __do_fast_syscall_32+0x127/0x180 arch/x86/entry/common.c:142
 do_fast_syscall_32+0x77/0xd0 arch/x86/entry/common.c:168
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:211
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f01549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f54da5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 000000000004ffe0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:120 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:103
 kmsan_slab_alloc+0x8e/0xe0 mm/kmsan/kmsan_hooks.c:76
 slab_alloc_node mm/slub.c:2922 [inline]
 kmem_cache_alloc_node+0x98b/0x1180 mm/slub.c:2959
 scsi_alloc_sense_buffer drivers/scsi/scsi_lib.c:77 [inline]
 scsi_mq_init_request+0x1f1/0x7a0 drivers/scsi/scsi_lib.c:1758
 blk_mq_init_request block/blk-mq.c:2377 [inline]
 blk_mq_alloc_rqs+0xbb4/0x1070 block/blk-mq.c:2447
 __blk_mq_alloc_map_and_request block/blk-mq.c:2776 [inline]
 __blk_mq_alloc_rq_maps block/blk-mq.c:3283 [inline]
 blk_mq_alloc_map_and_requests block/blk-mq.c:3309 [inline]
 blk_mq_alloc_tag_set+0x140e/0x2570 block/blk-mq.c:3468
 scsi_mq_setup_tags+0x7cb/0x800 drivers/scsi/scsi_lib.c:1929
 scsi_add_host_with_dma+0x365/0x14b0 drivers/scsi/hosts.c:227
 scsi_add_host include/scsi/scsi_host.h:762 [inline]
 virtscsi_probe+0xd8e/0x2d90 drivers/scsi/virtio_scsi.c:908
 virtio_dev_probe+0xfe5/0x16f0 drivers/virtio/virtio.c:261
 really_probe+0xd16/0x24d0 drivers/base/dd.c:557
 driver_probe_device+0x29d/0x3a0 drivers/base/dd.c:743
 device_driver_attach+0x25a/0x490 drivers/base/dd.c:1018
 __driver_attach+0x78c/0x840 drivers/base/dd.c:1095
 bus_for_each_dev+0x210/0x340 drivers/base/bus.c:305
 driver_attach+0x89/0xb0 drivers/base/dd.c:1111
 bus_add_driver+0x684/0xc50 drivers/base/bus.c:622
 driver_register+0x485/0x8e0 drivers/base/driver.c:171
 register_virtio_driver+0x11a/0x170 drivers/virtio/virtio.c:312
 INIT_LIST_HEAD include/linux/list.h:35 [inline]
 init+0x166/0x315 drivers/char/virtio_console.c:2250
 do_one_initcall+0x362/0x8d0 init/main.c:1229
 do_initcall_level+0x1e7/0x35a init/main.c:1302
 do_initcalls+0x127/0x1cb init/main.c:1318
 do_basic_setup+0x33/0x36 init/main.c:1338
 kernel_init_freeable+0x287/0x3cc init/main.c:1540
 kernel_init+0x1f/0x840 init/main.c:1427
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
=====================================================