=============================
WARNING: suspicious RCU usage
6.15.0-syzkaller-12426-ge271ed52b344 #0 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1394 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz.0.3503/18508:
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: __fib6_clean_all+0x9b/0x380 net/ipv6/ip6_fib.c:2316
#2: ffff88803454ac30 (&tb->tb6_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#2: ffff88803454ac30 (&tb->tb6_lock){+...}-{3:3}, at: __fib6_clean_all+0x1ce/0x380 net/ipv6/ip6_fib.c:2320
stack backtrace:
CPU: 1 UID: 0 PID: 18508 Comm: syz.0.3503 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
__fib6_update_sernum_upto_root+0x223/0x230 net/ipv6/ip6_fib.c:1393
fib6_update_sernum_upto_root+0x125/0x190 net/ipv6/ip6_fib.c:1407
fib6_ifup+0x142/0x180 net/ipv6/route.c:4871
fib6_clean_node+0x24a/0x590 net/ipv6/ip6_fib.c:2252
fib6_walk_continue+0x678/0x910 net/ipv6/ip6_fib.c:2177
fib6_walk+0x149/0x290 net/ipv6/ip6_fib.c:2225
fib6_clean_tree net/ipv6/ip6_fib.c:2305 [inline]
__fib6_clean_all+0x234/0x380 net/ipv6/ip6_fib.c:2321
rt6_sync_up+0x128/0x160 net/ipv6/route.c:4890
addrconf_notify+0xd55/0x1010 net/ipv6/addrconf.c:3732
notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
netif_state_change+0x284/0x3a0 net/core/dev.c:1584
do_setlink+0x35de/0x41c0 net/core/rtnetlink.c:3388
rtnl_group_changelink net/core/rtnetlink.c:3773 [inline]
__rtnl_newlink net/core/rtnetlink.c:3927 [inline]
rtnl_newlink+0x149f/0x1c70 net/core/rtnetlink.c:4055
rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944
netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x219/0x270 net/socket.c:727
____sys_sendmsg+0x505/0x830 net/socket.c:2566
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
__sys_sendmsg net/socket.c:2652 [inline]
__do_sys_sendmsg net/socket.c:2657 [inline]
__se_sys_sendmsg net/socket.c:2655 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f854178e929
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:00007f854254f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f85419b6240 RCX: 00007f854178e929
RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000005
RBP: 00007f8541810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f85419b6240 R15: 00007f8541adfa28
=============================
WARNING: suspicious RCU usage
6.15.0-syzkaller-12426-ge271ed52b344 #0 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1401 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz.0.3503/18508:
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f50f648 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#1: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: __fib6_clean_all+0x9b/0x380 net/ipv6/ip6_fib.c:2316
#2: ffff88803454ac30 (&tb->tb6_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#2: ffff88803454ac30 (&tb->tb6_lock){+...}-{3:3}, at: __fib6_clean_all+0x1ce/0x380 net/ipv6/ip6_fib.c:2320
stack backtrace:
CPU: 1 UID: 0 PID: 18508 Comm: syz.0.3503 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
__fib6_update_sernum_upto_root+0x18e/0x230 net/ipv6/ip6_fib.c:1400
fib6_update_sernum_upto_root+0x125/0x190 net/ipv6/ip6_fib.c:1407
fib6_ifup+0x142/0x180 net/ipv6/route.c:4871
fib6_clean_node+0x24a/0x590 net/ipv6/ip6_fib.c:2252
fib6_walk_continue+0x678/0x910 net/ipv6/ip6_fib.c:2177
fib6_walk+0x149/0x290 net/ipv6/ip6_fib.c:2225
fib6_clean_tree net/ipv6/ip6_fib.c:2305 [inline]
__fib6_clean_all+0x234/0x380 net/ipv6/ip6_fib.c:2321
rt6_sync_up+0x128/0x160 net/ipv6/route.c:4890
addrconf_notify+0xd55/0x1010 net/ipv6/addrconf.c:3732
notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
netif_state_change+0x284/0x3a0 net/core/dev.c:1584
do_setlink+0x35de/0x41c0 net/core/rtnetlink.c:3388
rtnl_group_changelink net/core/rtnetlink.c:3773 [inline]
__rtnl_newlink net/core/rtnetlink.c:3927 [inline]
rtnl_newlink+0x149f/0x1c70 net/core/rtnetlink.c:4055
rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944
netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x219/0x270 net/socket.c:727
____sys_sendmsg+0x505/0x830 net/socket.c:2566
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
__sys_sendmsg net/socket.c:2652 [inline]
__do_sys_sendmsg net/socket.c:2657 [inline]
__se_sys_sendmsg net/socket.c:2655 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f854178e929
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:00007f854254f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f85419b6240 RCX: 00007f854178e929
RDX: 0000000000000000 RSI: 0000200000000280 RDI: 0000000000000005
RBP: 00007f8541810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f85419b6240 R15: 00007f8541adfa28
bond0: (slave bond_slave_0): Releasing backup interface
bond0: (slave bond_slave_1): Releasing backup interface
team0: Port device team_slave_0 removed
team0: Port device team_slave_1 removed
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1