syzbot

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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in copyout+0xbc/0x100 lib/iov_iter.c:169
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout+0xbc/0x100 lib/iov_iter.c:169
 _copy_to_iter+0x5ce/0x1fe0 lib/iov_iter.c:527
 copy_to_iter include/linux/uio.h:176 [inline]
 simple_copy_to_iter+0x64/0xa0 net/core/datagram.c:513
 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419
 skb_copy_datagram_iter+0x53/0x1d0 net/core/datagram.c:527
 skb_copy_datagram_msg include/linux/skbuff.h:3879 [inline]
 netlink_recvmsg+0x4d1/0x1720 net/netlink/af_netlink.c:1977
 sock_recvmsg_nosec net/socket.c:995 [inline]
 sock_recvmsg net/socket.c:1013 [inline]
 __sys_recvfrom+0x5b8/0x850 net/socket.c:2169
 __do_sys_recvfrom net/socket.c:2187 [inline]
 __se_sys_recvfrom net/socket.c:2183 [inline]
 __x64_sys_recvfrom+0x122/0x1c0 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:358 [inline]
 __alloc_skb+0x346/0xcf0 net/core/skbuff.c:430
 alloc_skb include/linux/skbuff.h:1257 [inline]
 netlink_dump+0x2da/0x1400 net/netlink/af_netlink.c:2248
 __netlink_dump_start+0xa91/0xc60 net/netlink/af_netlink.c:2380
 netlink_dump_start include/linux/netlink.h:245 [inline]
 rtnetlink_rcv_msg+0x13c0/0x1860 net/core/rtnetlink.c:6046
 netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501
 rtnetlink_rcv+0x30/0x40 net/core/rtnetlink.c:6108
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg net/socket.c:2565 [inline]
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Byte 17 of 560 is uninitialized
Memory access of size 560 starts at ffff88810e6e6000
Data copied to user address 00007fff2e011610

CPU: 0 PID: 3484 Comm: syz-executor350 Not tainted 6.0.0-rc2-syzkaller-47461-gac3859c02d7f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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