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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
 kmsan_get_metadata+0x1a2/0x1d0 mm/kmsan/shadow.c:151
 kmsan_internal_set_shadow_origin+0x69/0x100 mm/kmsan/core.c:225
 __msan_poison_alloca+0x15e/0x1b0 mm/kmsan/instrumentation.c:288
 zap_pte_range mm/memory.c:1592 [inline]
 zap_pmd_range mm/memory.c:1724 [inline]
 zap_pud_range mm/memory.c:1753 [inline]
 zap_p4d_range mm/memory.c:1774 [inline]
 unmap_page_range+0x1073/0x8160 mm/memory.c:1795
 unmap_single_vma+0x380/0x490 mm/memory.c:1841
 unmap_vmas+0x34a/0x610 mm/memory.c:1885
 unmap_region+0x1d7/0x390 mm/mmap.c:2365
 do_vmi_align_munmap+0x128f/0x1c40 mm/mmap.c:2683
 do_vmi_munmap+0x45d/0x4f0 mm/mmap.c:2759
 mmap_region+0xe59/0x4420 mm/mmap.c:2810
 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
 __x64_sys_ioctl+0x96/0xe0 fs/ioctl.c:893
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 PID: 4797 Comm: cmp Not tainted 6.10.0-rc4-syzkaller-00052-ge5b3efbe1ab1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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