kernel: protection fault trap, code=0
Stopped at m_extfree+0x3d: movq %rax,0x90(%r15)
ddb>
ddb> set $lines = 0
ddb> show panic
the kernel did not panic
ddb> trace
m_extfree(da3dcd11548f7e3f) at m_extfree+0x3d
m_free(ffffff006db88400) at m_free+0xee
m_freem(16) at m_freem+0x2d
soreceive(0,ffffff006e6fea88,0,0,ffff8000210fcc50,ffff8000210fcb60) at soreceive+0x1131
recvit(ffff8000210fcc80,ffff8000210fcd88,ffff8000210fcd70,ffff8000210c3078,0) at recvit+0x28c
sys_recvmsg(ffff8000210fce10,ffff8000210c3078,ffff8000210a5660) at sys_recvmsg+0x120
syscall(0) at syscall+0x3e4
Xsyscall(6,0,0,0,1,7f7fffff21a8) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff2160, count: -8
ddb> show registers
rdi 0x7
rsi 0x42
rbp 0xffff8000210fca50
rbx 0
rdx 0xffffffffffffbeef
rcx 0xffffffff81e8e3b0 mbstat_boot_boot_cpumem
rax 0x371496c40e18ba99
r8 0
r9 0xffff8000210c3078
r10 0xda3dcd11548f7e3f
r11 0xffffffff816a34a0 pool_lock_mtx_leave
r12 0xdead __ALIGN_SIZE+0xcead
r13 0xffffff006e6fea88
r14 0xffffff006db88400
r15 0x307c2f590a204b3c
rip 0xffffffff81adbf1d m_extfree+0x3d
cs 0x8
rflags 0x10246 __ALIGN_SIZE+0xf246
rsp 0xffff8000210fca40
ss 0x10
m_extfree+0x3d: movq %rax,0x90(%r15)
ddb> show proc
PROC (syz-executor8170) pid=96642 stat=onproc
flags process=2<EXEC> proc=0
pri=50, usrpri=50, nice=20
forw=0xffffffffffffffff, list=0xffff8000210c32d0,0xffffffff81eafaa0
process=0xffff8000210a5660 user=0xffff8000210f7000, vmspace=0xffffff007f12b528
estcpu=0, cpticks=1, pctcpu=0.0
user=0, sys=1, intr=0
ddb> ps
PID TID PPID UID S FLAGS WAIT COMMAND
*49901 96642 36687 0 7 0x2 syz-executor8170
36687 1941 64844 0 3 0x10008a pause ksh
64844 149296 32328 0 3 0x92 select sshd
33033 329785 1 0 3 0x100083 ttyin getty
32328 468257 1 0 3 0x80 select sshd
67061 368879 40352 73 3 0x100090 kqread syslogd
40352 238667 1 0 3 0x100082 netio syslogd
41089 275142 1 77 3 0x100090 poll dhclient
58298 351436 1 0 3 0x80 poll dhclient
99277 312932 0 0 2 0x14200 zerothread
92306 334436 0 0 3 0x14200 aiodoned aiodoned
2795 448611 0 0 3 0x14200 syncer update
85307 328015 0 0 3 0x14200 cleaner cleaner
49730 420142 0 0 3 0x14200 reaper reaper
88669 404666 0 0 3 0x14200 pgdaemon pagedaemon
35323 210131 0 0 3 0x14200 bored crynlk
88011 297031 0 0 3 0x14200 bored crypto
36143 35021 0 0 3 0x40014200 acpi0 acpi0
37234 125684 0 0 3 0x14200 bored softnet
30399 2859 0 0 3 0x14200 bored systqmp
6370 291812 0 0 3 0x14200 bored systq
12619 110843 0 0 3 0x40014200 bored softclock
1096 371011 0 0 3 0x40014200 idle0
1 259157 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb>