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BUG: KMSAN: uninit-value in ethnl_set_linkmodes+0x1739/0x2490
 ethnl_set_linkmodes+0x1739/0x2490
 genl_rcv_msg+0x1526/0x1620
 netlink_rcv_skb+0x41a/0x7a0
 genl_rcv+0x67/0x90
 netlink_unicast+0x10a0/0x1370
 netlink_sendmsg+0x14e1/0x1720
 ____sys_sendmsg+0xe14/0x12c0
 ___sys_sendmsg+0x471/0x510
 __x64_sys_sendmsg+0x3f0/0x570
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 tun_get_link_ksettings+0x82/0xb0
 __ethtool_get_link_ksettings+0x1fe/0x310
 ethnl_set_linkmodes+0x569/0x2490
 genl_rcv_msg+0x1526/0x1620
 netlink_rcv_skb+0x41a/0x7a0
 genl_rcv+0x67/0x90
 netlink_unicast+0x10a0/0x1370
 netlink_sendmsg+0x14e1/0x1720
 ____sys_sendmsg+0xe14/0x12c0
 ___sys_sendmsg+0x471/0x510
 __x64_sys_sendmsg+0x3f0/0x570
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 tun_set_link_ksettings+0x82/0xb0
 ethtool_set_link_ksettings+0x74f/0x850
 dev_ethtool+0x1ed1/0x28a0
 dev_ioctl+0x573/0x16f0
 sock_do_ioctl+0x3e7/0x6d0
 sock_ioctl+0xa0e/0xf80
 __se_sys_ioctl+0x2e1/0x4a0
 __x64_sys_ioctl+0xdc/0x120
 do_syscall_64+0x3d/0xb0
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Local variable link_ksettings created at:
 ethtool_set_link_ksettings+0x85/0x850
 dev_ethtool+0x1ed1/0x28a0

CPU: 1 PID: 30385 Comm: syz-executor.3 Not tainted 5.18.0-syzkaller-16253-g2f3064574275 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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