------------[ cut here ]------------
err == -EMSGSIZE
WARNING: net/core/rtnetlink.c:4538 at rtmsg_ifinfo_build_skb+0x21c/0x260 net/core/rtnetlink.c:4538, CPU#1: syz.4.15299/6530
Modules linked in:
CPU: 1 UID: 0 PID: 6530 Comm: syz.4.15299 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(lazy)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rtmsg_ifinfo_build_skb+0x21c/0x260 net/core/rtnetlink.c:4538
Code: f6 ba 01 00 00 00 89 e9 e8 41 d5 3a 00 4c 89 f0 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 8b 31 29 02 cc e8 15 a8 a7 f8 90 <0f> 0b 90 eb 8f 44 89 e1 80 e1 07 fe c1 38 c1 0f 8c 8b fe ff ff 4c
RSP: 0018:ffffc90006aee7e8 EFLAGS: 00010283
RAX: ffffffff891e201b RBX: 1ffff11004f1c821 RCX: 0000000000080000
RDX: ffffc90006c11000 RSI: 00000000000068a3 RDI: 00000000000068a4
RBP: 00000000ffffffa6 R08: 0000000000000000 R09: 0000000000000000
R10: fffff52000d5dca4 R11: 0000000000000020 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88803a7a8280 R15: ffff8880278e4000
FS:  00007f8587b466c0(0000) GS:ffff888125d46000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003038 CR3: 00000000379a0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rtmsg_ifinfo_event net/core/rtnetlink.c:4566 [inline]
 rtnetlink_event+0x1b7/0x270 net/core/rtnetlink.c:7136
 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
 call_netdevice_notifiers net/core/dev.c:2302 [inline]
 netdev_features_change net/core/dev.c:1590 [inline]
 netdev_update_features net/core/dev.c:11108 [inline]
 netif_disable_lro+0xdd/0x4b0 net/core/dev.c:1831
 ipv6_add_dev+0x4b7/0x1400 net/ipv6/addrconf.c:409
 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3685
 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
 call_netdevice_notifiers net/core/dev.c:2302 [inline]
 register_netdevice+0x18c0/0x1ed0 net/core/dev.c:11484
 macsec_newlink+0x706/0x1200 drivers/net/macsec.c:4221
 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3913
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x565/0x870 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b7/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85898ee0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8587b46028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8589b75fa0 RCX: 00007f85898ee0d9
RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000004
RBP: 00007f8589985024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8589b76038 R14: 00007f8589b75fa0 R15: 00007ffceb3b2cf8
 </TASK>