panic: in_cksum: out of data, len 63
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 147866   8639      0           0          0    1  syz-executor.1
*292363  36016      0           0  0x4000000    0K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:212
in_cksum(fffffd8065f8a500,3c) at in_cksum+0x6f8
ip_input_if(ffff800020c0b158,ffff800020c0b164,4,0,ffff800000a0b000) at ip_input_if+0x32c sys/netinet/ip_input.c:310
ipv4_input(ffff800000a0b000,fffffd8065f8a500) at ipv4_input+0x48 sys/netinet/ip_input.c:255
tun_dev_write(ffff800000a0b000,ffff800020c0b500,3c9) at tun_dev_write+0x418 sys/net/if_tun.c:932
spec_write(ffff800020c0b2e8) at spec_write+0xd7 sys/kern/spec_vnops.c:310
VOP_WRITE(fffffd806471ab98,ffff800020c0b500,1,fffffd807f7c66c0) at VOP_WRITE+0x6a sys/kern/vfs_vops.c:268
vn_write(fffffd80675f8dc0,ffff800020c0b500,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:397
dofilewritev(ffff800020b39128,3,ffff800020c0b500,0,ffff800020c0b610) at dofilewritev+0x1ac sys/kern/sys_generic.c:364
sys_writev(ffff800020b39128,ffff800020c0b5a8,ffff800020c0b610) at sys_writev+0xa7 sys/kern/sys_generic.c:311
syscall(ffff800020c0b680) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800020c0b680) at syscall+0x552 sys/arch/amd64/amd64/trap.c:554
Xsyscall(6,0,d,0,3,78fa9fa4010) at Xsyscall+0x128
end of kernel
end trace frame: 0x7922cd19c70, count: 2
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