------------[ cut here ]------------
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib6_event_init drivers/net/netdevsim/fib.c:831 [inline], CPU#1: syz.3.135/6536
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib6_prepare_event drivers/net/netdevsim/fib.c:947 [inline], CPU#1: syz.3.135/6536
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:1003 [inline], CPU#1: syz.3.135/6536
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib_event_nb+0xed8/0x1080 drivers/net/netdevsim/fib.c:1043, CPU#1: syz.3.135/6536
Modules linked in:
CPU: 1 UID: 0 PID: 6536 Comm: syz.3.135 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:nsim_fib6_event_init drivers/net/netdevsim/fib.c:831 [inline]
RIP: 0010:nsim_fib6_prepare_event drivers/net/netdevsim/fib.c:947 [inline]
RIP: 0010:nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:1003 [inline]
RIP: 0010:nsim_fib_event_nb+0xed8/0x1080 drivers/net/netdevsim/fib.c:1043
Code: fa be 02 00 00 00 eb 0a e8 55 fa e0 fa be 01 00 00 00 4c 89 f7 e8 d8 26 aa fd 4c 8b 64 24 08 e9 91 f4 ff ff e8 39 fa e0 fa 90 <0f> 0b 90 e9 70 fb ff ff 44 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 35
RSP: 0018:ffffc9001b627008 EFLAGS: 00010287
RAX: ffffffff86e05027 RBX: 0000000000000001 RCX: 0000000000080000
RDX: ffffc9000e45d000 RSI: 00000000000004b7 RDI: 00000000000004b8
RBP: dffffc0000000000 R08: ffff88805992002f R09: 1ffff1100b324005
R10: dffffc0000000000 R11: ffffed100b324006 R12: ffff88807f343000
R13: ffffc9001b627180 R14: 0000000000000000 R15: ffffc9001b627198
FS:  00007fa66d7b46c0(0000) GS:ffff8881261b1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000002453e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
 atomic_notifier_call_chain+0xda/0x180 kernel/notifier.c:223
 call_fib_notifiers+0x31/0x60 net/core/fib_notifier.c:35
 call_fib6_multipath_entry_notifiers+0xe6/0x150 net/ipv6/ip6_fib.c:425
 ip6_route_multipath_add net/ipv6/route.c:5525 [inline]
 inet6_rtm_newroute+0x12f5/0x18c0 net/ipv6/route.c:5647
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:733
 ____sys_sendmsg+0x505/0x820 net/socket.c:2608
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2662
 __sys_sendmsg net/socket.c:2694 [inline]
 __do_sys_sendmsg net/socket.c:2699 [inline]
 __se_sys_sendmsg net/socket.c:2697 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2697
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa66f58f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa66d7b4038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa66f7e6180 RCX: 00007fa66f58f749
RDX: 0000000000040000 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007fa66f613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa66f7e6218 R14: 00007fa66f7e6180 R15: 00007ffda98ff8a8
 </TASK>