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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:6722
 napi_poll net/core/dev.c:6791 [inline]
 net_rx_action+0x82a/0x1850 net/core/dev.c:6907
 handle_softirqs+0x1ce/0x800 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0x68/0x120 kernel/softirq.c:637
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:649
 common_interrupt+0x94/0xa0 arch/x86/kernel/irq.c:278
 asm_common_interrupt+0x2b/0x40 arch/x86/include/asm/idtentry.h:693
 smap_restore arch/x86/include/asm/smap.h:56 [inline]
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:37 [inline]
 __msan_metadata_ptr_for_load_8+0x2c/0x40 mm/kmsan/instrumentation.c:92
 vma_set_page_prot+0x321/0x800 mm/mmap.c:101
 mmap_region+0x40d1/0x4420 mm/mmap.c:2998
 do_mmap+0xfc5/0x1a40 mm/mmap.c:1397
 vm_mmap_pgoff+0x23b/0x5a0 mm/util.c:573
 ksys_mmap_pgoff+0x5cb/0x7a0 mm/mmap.c:1443
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:79 [inline]
 __x64_sys_mmap+0x1a8/0x240 arch/x86/kernel/sys_x86_64.c:79
 x64_sys_call+0x1bfc/0x3b90 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_pages_noprof+0x9d6/0xe70 mm/page_alloc.c:4701
 alloc_pages_mpol_noprof+0x299/0x990 mm/mempolicy.c:2265
 alloc_pages_noprof+0x1bf/0x1e0 mm/mempolicy.c:2336
 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:8781
 dev_change_flags+0x8e/0x1d0 net/core/dev.c:8853
 devinet_ioctl+0x13ec/0x22c0 net/ipv4/devinet.c:1177
 inet_ioctl+0x4bd/0x6d0 net/ipv4/af_inet.c:1003
 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:907 [inline]
 __se_sys_ioctl+0x261/0x450 fs/ioctl.c:893
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:893
 x64_sys_call+0x18c0/0x3b90 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 PID: 4775 Comm: cmp Not tainted 6.10.0-rc3-syzkaller-00249-gb5beaa44747b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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