panic: m_copydata: null mbuf
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 432009   1556      0           0  0x4000080    0  syz-executor.1
*246902  72346      0     0x14000      0x200    1  softnet
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff8226a204) at panic+0x15c sys/kern/subr_prf.c:207
m_copydata(fffffd806384de00,30,2,ffff800020a4f248) at m_copydata+0x17e m_getptr sys/kern/uipc_mbuf.c:1031 [inline]
m_copydata(fffffd806384de00,30,2,ffff800020a4f248) at m_copydata+0x17e sys/kern/uipc_mbuf.c:722
ip6_pullexthdr(fffffd806384de00,30,0) at ip6_pullexthdr+0xa2 sys/netinet6/ip6_input.c:1146
ip6_savecontrol(fffffd806f6f1000,fffffd806384de00,ffff800020a4f3b0) at ip6_savecontrol+0x373 sys/netinet6/ip6_input.c:1056
rip6_input(ffff800020a4f5f8,ffff800020a4f604,0,18) at rip6_input+0x50b sys/netinet6/raw_ip6.c:206
ip_deliver(ffff800020a4f5f8,ffff800020a4f604,0,18) at ip_deliver+0x353 sys/netinet/ip_input.c:668
ip6_input_if(ffff800020a4f5f8,ffff800020a4f604,29,0,ffff800000679800) at ip6_input_if+0x17e1 ip6_ours sys/netinet6/ip6_input.c:538 [inline]
ip6_input_if(ffff800020a4f5f8,ffff800020a4f604,29,0,ffff800000679800) at ip6_input_if+0x17e1 sys/netinet6/ip6_input.c:471
ipv6_input(ffff800000679800,fffffd8063755100) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171
if_input_local(ffff800000679800,fffffd8063755100,18) at if_input_local+0x121 sys/net/if.c:780
loinput(ffff800000679800,fffffd8063755100,0) at loinput+0x4f sys/net/if_loop.c:239
if_input_process(ffff800000679800,ffff800020a4f768) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline]
if_input_process(ffff800000679800,ffff800020a4f768) at if_input_process+0xfb sys/net/if.c:943
ifiq_process(ffff800000679bf8) at ifiq_process+0x80 sys/net/ifq.c:646
taskq_thread(ffff80000002b080) at taskq_thread+0x9c sys/kern/kern_task.c:369
end trace frame: 0x0, count: 1
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