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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:167 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x376/0x1c60 lib/iov_iter.c:316
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copyout lib/iov_iter.c:167 [inline]
 _copy_to_iter+0x376/0x1c60 lib/iov_iter.c:316
 copy_to_iter include/linux/uio.h:194 [inline]
 simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:513
 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419
 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:527
 skb_copy_datagram_msg include/linux/skbuff.h:3942 [inline]
 netlink_recvmsg+0x4ae/0x1620 net/netlink/af_netlink.c:1971
 sock_recvmsg_nosec net/socket.c:1020 [inline]
 sock_recvmsg net/socket.c:1041 [inline]
 sock_read_iter+0x467/0x580 net/socket.c:1107
 call_read_iter include/linux/fs.h:1865 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x8fc/0xf50 fs/read_write.c:470
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3470 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3509
 __do_kmalloc_node mm/slab_common.c:984 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1005
 kmalloc_reserve+0x248/0x470 net/core/skbuff.c:575
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1289 [inline]
 netlink_dump+0x2ab/0x1310 net/netlink/af_netlink.c:2242
 __netlink_dump_start+0xb1c/0xcf0 net/netlink/af_netlink.c:2376
 netlink_dump_start include/linux/netlink.h:330 [inline]
 rtnetlink_rcv_msg+0x139d/0x1840 net/core/rtnetlink.c:6380
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2549
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6442
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0xf28/0x1230 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x122f/0x13d0 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmsg net/socket.c:2577 [inline]
 __do_sys_sendmsg net/socket.c:2586 [inline]
 __se_sys_sendmsg net/socket.c:2584 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2584
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Bytes 32-35 of 44 are uninitialized
Memory access of size 44 starts at ffff8880a8418000
Data copied to user address 0000000020000380

CPU: 1 PID: 6403 Comm: syz-executor.4 Not tainted 6.5.0-rc2-syzkaller-00307-gd192f5382581 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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