syzbot

IPv6: RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE
IPv6: NLM_F_CREATE should be set when creating new route
IPv6: NLM_F_CREATE should be set when creating new route
------------[ cut here ]------------
i != fen6_info->nsiblings
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib6_event_init drivers/net/netdevsim/fib.c:831 [inline], CPU#0: syz.0.17/5984
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib6_prepare_event drivers/net/netdevsim/fib.c:947 [inline], CPU#0: syz.0.17/5984
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:1003 [inline], CPU#0: syz.0.17/5984
WARNING: drivers/net/netdevsim/fib.c:831 at nsim_fib_event_nb+0x1060/0x1210 drivers/net/netdevsim/fib.c:1043, CPU#0: syz.0.17/5984
Modules linked in:
CPU: 0 UID: 0 PID: 5984 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0x1060/0x1210 drivers/net/netdevsim/fib.c:1043
Code: 00 00 00 48 89 df e8 df 1d 8e fd 49 bf 00 00 00 00 00 fc ff df 4c 8b 74 24 38 4c 8b 64 24 20 e9 1d f3 ff ff e8 11 70 a5 fa 90 <0f> 0b 90 e9 d3 f9 ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c b7 f0
RSP: 0018:ffffc900039c6fc8 EFLAGS: 00010293
RAX: ffffffff87201bbf RBX: 0000000000000002 RCX: ffff888025ae3c80
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffffc900039c7160 R08: ffff88807c59742f R09: 1ffff1100f8b2e85
R10: dffffc0000000000 R11: ffffed100f8b2e86 R12: ffff88807c597818
R13: 0000000000000001 R14: ffffc900039c7178 R15: dffffc0000000000
FS:  000055555d59e500(0000) GS:ffff888125464000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000076c12000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 notifier_call_chain+0x1be/0x400 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+0xf5/0x160 net/ipv6/ip6_fib.c:425
 ip6_route_multipath_add net/ipv6/route.c:5535 [inline]
 inet6_rtm_newroute+0x14a2/0x19e0 net/ipv6/route.c:5657
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1236b9c799
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:00007ffc6e1f5d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1236e15fa0 RCX: 00007f1236b9c799
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f1236c32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1236e15fac R14: 00007f1236e15fa0 R15: 00007f1236e15fa0
 </TASK>