=============================
WARNING: suspicious RCU usage
4.14.106+ #30 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1590 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-executor.4/6810:
 #0:  (rtnl_mutex){+.+.}, at: [<ffffffff8437c390>] dev_ioctl+0x260/0xca0 net/core/dev_ioctl.c:565
 #1:  (rcu_read_lock){....}, at: [<ffffffff846e6690>] __fib6_clean_all+0x0/0x230 net/ipv6/ip6_fib.c:1823
 #2:  (&tb->tb6_lock){++--}, at: [<ffffffff846e676e>] __fib6_clean_all+0xde/0x230 net/ipv6/ip6_fib.c:1837

stack backtrace:
CPU: 0 PID: 6810 Comm: syz-executor.4 Not tainted 4.14.106+ #30
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x10e lib/dump_stack.c:53
 fib6_del+0x8c2/0xbe0 net/ipv6/ip6_fib.c:1590
 fib6_clean_node+0x270/0x440 net/ipv6/ip6_fib.c:1777
 fib6_walk_continue+0x3a5/0x5f0 net/ipv6/ip6_fib.c:1703
 fib6_walk+0x8d/0xe0 net/ipv6/ip6_fib.c:1748
 fib6_clean_tree+0xd4/0x110 net/ipv6/ip6_fib.c:1822
 __fib6_clean_all+0xf5/0x230 net/ipv6/ip6_fib.c:1838
 rt6_ifdown+0x90/0x5b0 net/ipv6/route.c:2868
 addrconf_ifdown+0xc5/0x13b0 net/ipv6/addrconf.c:3602
selinux_nlmsg_perm: 390 callbacks suppressed
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=7006 comm=syz-executor.0
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl3 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl3 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl3 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
audit: type=1326 audit(2000000009.090:1125): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=228 compat=0 ip=0x45aeda code=0x50000
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl3 xmit: Local address not yet configured!
audit: type=1326 audit(2000000009.140:1126): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x458079 code=0x50000
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!
audit: type=1326 audit(2000000009.140:1127): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x458079 code=0x50000
audit: type=1326 audit(2000000009.150:1128): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x458079 code=0x50000
tmpfs: Bad mount option �I�w����`C��C`3-� fS�N<s��p�:�s꣢�d��k�|<zt��!�;;|�L6��Dd�/�Ĩl�8
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
audit: type=1326 audit(2000000009.160:1129): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=228 compat=0 ip=0x45aeda code=0x50000
tmpfs: Bad mount option �I�w����`C��C`3-� fS�N<s��p�:�s꣢�d��k�|<zt��!�;;|�L6��Dd�/�Ĩl�8
audit: type=1326 audit(2000000009.170:1130): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=319 compat=0 ip=0x458079 code=0x50000
ip6_tunnel: ip6tnl2 xmit: Local address not yet configured!
audit: type=1326 audit(2000000009.170:1131): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=77 compat=0 ip=0x458047 code=0x50000
audit: type=1326 audit(2000000009.180:1132): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=2 compat=0 ip=0x412011 code=0x50000
audit: type=1326 audit(2000000009.190:1133): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=16 compat=0 ip=0x457ee7 code=0x50000
audit: type=1326 audit(2000000009.200:1134): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=7281 comm="syz-executor.1" exe="/root/syz-executor.1" sig=0 arch=c000003e syscall=16 compat=0 ip=0x457ee7 code=0x50000
ip6_tunnel: ip6tnl3 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl4 xmit: Local address not yet configured!