=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak in iterate_ubuf include/linux/iov_iter.h:29 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x366/0x2520 lib/iov_iter.c:185
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x366/0x2520 lib/iov_iter.c:185
 copy_to_iter include/linux/uio.h:196 [inline]
 simple_copy_to_iter net/core/datagram.c:532 [inline]
 __skb_datagram_iter+0x185/0x1000 net/core/datagram.c:420
 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546
 skb_copy_datagram_msg include/linux/skbuff.h:3970 [inline]
 netlink_recvmsg+0x432/0x1610 net/netlink/af_netlink.c:1965
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg+0x2c4/0x340 net/socket.c:1068
 __sys_recvfrom+0x35a/0x5f0 net/socket.c:2242
 __do_sys_recvfrom net/socket.c:2260 [inline]
 __se_sys_recvfrom net/socket.c:2256 [inline]
 __x64_sys_recvfrom+0x126/0x1d0 net/socket.c:2256
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3819 [inline]
 slab_alloc_node mm/slub.c:3860 [inline]
 __do_kmalloc_node mm/slub.c:3980 [inline]
 __kmalloc_node_track_caller+0x747/0x1060 mm/slub.c:4001
 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582
 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1296 [inline]
 netlink_dump+0x2ab/0x1330 net/netlink/af_netlink.c:2237
 __netlink_dump_start+0xb24/0xcf0 net/netlink/af_netlink.c:2370
 netlink_dump_start include/linux/netlink.h:338 [inline]
 rtnetlink_rcv_msg+0x13a4/0x1850 net/core/rtnetlink.c:6573
 netlink_rcv_skb+0x375/0x650 net/netlink/af_netlink.c:2543
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6635
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0xf4c/0x1260 net/netlink/af_netlink.c:1367
 netlink_sendmsg+0x123d/0x13e0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x4a0 net/socket.c:2674
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Bytes 32-35 of 44 are uninitialized
Memory access of size 44 starts at ffff888117c09000
Data copied to user address 0000000020000940

CPU: 1 PID: 5433 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller-01185-g855684c7d938 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
=====================================================