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BUG: KMSAN: uninit-value in receive_mergeable drivers/net/virtio_net.c:1839 [inline]
BUG: KMSAN: uninit-value in receive_buf+0x25e3/0x5fd0 drivers/net/virtio_net.c:1955
 receive_mergeable drivers/net/virtio_net.c:1839 [inline]
 receive_buf+0x25e3/0x5fd0 drivers/net/virtio_net.c:1955
 virtnet_receive drivers/net/virtio_net.c:2259 [inline]
 virtnet_poll+0xd1c/0x23c0 drivers/net/virtio_net.c:2362
 __napi_poll+0xe7/0x980 net/core/dev.c:6721
 napi_poll net/core/dev.c:6790 [inline]
 net_rx_action+0x82a/0x1850 net/core/dev.c:6906
 handle_softirqs+0x1d8/0x810 kernel/softirq.c:554
 run_ksoftirqd+0x29/0x50 kernel/softirq.c:928
 smpboot_thread_fn+0x555/0xa60 kernel/smpboot.c:164
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
 skb_page_frag_refill+0x2bf/0x7c0 net/core/sock.c:2920
 virtnet_rq_alloc+0x43/0xbb0 drivers/net/virtio_net.c:882
 add_recvbuf_mergeable drivers/net/virtio_net.c:2110 [inline]
 try_fill_recv+0x3f0/0x2f50 drivers/net/virtio_net.c:2155
 virtnet_open+0x1cc/0xb00 drivers/net/virtio_net.c:2434
 __dev_open+0x546/0x6f0 net/core/dev.c:1472
 __dev_change_flags+0x309/0x9a0 net/core/dev.c:8780
 dev_change_flags+0x8e/0x1d0 net/core/dev.c:8852
 devinet_ioctl+0x13ec/0x22c0 net/ipv4/devinet.c:1177
 inet_ioctl+0x4bd/0x6d0 net/ipv4/af_inet.c:1001
 sock_do_ioctl+0xb7/0x540 net/socket.c:1222
 sock_ioctl+0x727/0xd70 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x261/0x450 fs/ioctl.c:890
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:890
 x64_sys_call+0x1883/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.9.0-syzkaller-08414-g7ee332c9f12b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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