panic: malformed IPv4 option passed to ip_optcopy Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 302426 10376 0 0 0 1 syz-executor0 *101854 10376 0 0 0x4000000 0K syz-executor0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x147 sys/kern/subr_prf.c:208 ip_fragment(4d39f1f5ec35d986,ffffff006117f9d9,ffff800000173290) at ip_fragment+0x625 ip_output(4d39f1f5ec340f51,ffffff006f4a6690,ffffff006117f900,0,ffffff006f1da600,ffffff006f4a7a80) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(92f33cb3ae3c1531,1400,ffffff006f4a7a80,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(1d744b5e1165cc80,ffffff0076dd1350,ffff8000211a12e0,1000,ffff8000211a1390,0) at sosend+0x47a sys/kern/uipc_socket.c:513 dofilewritev(bcc36dbadadbea9a,ffff800021062270,ffff8000211a1390,1000,ffff8000211a13a8) at dofilewritev+0x14b sys/kern/sys_generic.c:364 sys_write(6b657212e3a12f6f,40,ffff800021062270) at sys_write+0x7b sys/kern/sys_generic.c:283 syscall(e30531bd6dcf802c) at syscall+0x496 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(e30531bd6dcf802c) at syscall+0x496 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,c,0,3,547ed52b010) at Xsyscall+0x128 end of kernel end trace frame: 0x54a08712b10, count: 5 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{0}> ddb{0}> set $lines = 0 ddb{0}> show panic malformed IPv4 option passed to ip_optcopy ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x147 sys/kern/subr_prf.c:208 ip_fragment(4d39f1f5ec35d986,ffffff006117f9d9,ffff800000173290) at ip_fragment+0x625 ip_output(4d39f1f5ec340f51,ffffff006f4a6690,ffffff006117f900,0,ffffff006f1da600,ffffff006f4a7a80) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(92f33cb3ae3c1531,1400,ffffff006f4a7a80,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(1d744b5e1165cc80,ffffff0076dd1350,ffff8000211a12e0,1000,ffff8000211a1390,0) at sosend+0x47a sys/kern/uipc_socket.c:513 dofilewritev(bcc36dbadadbea9a,ffff800021062270,ffff8000211a1390,1000,ffff8000211a13a8) at dofilewritev+0x14b sys/kern/sys_generic.c:364 sys_write(6b657212e3a12f6f,40,ffff800021062270) at sys_write+0x7b sys/kern/sys_generic.c:283 syscall(e30531bd6dcf802c) at syscall+0x496 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(e30531bd6dcf802c) at syscall+0x496 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,c,0,3,547ed52b010) at Xsyscall+0x128 end of kernel end trace frame: 0x54a08712b10, count: -10 ddb{0}> show registers rdi 0xffffffff81eeef78 kprintf_mutex rsi 0xffffffff81b0b167 db_enter+0x17 rbp 0xffff8000211a0f10 rbx 0xffff8000211a0fb0 rdx 0xffff80000093b000 rcx 0x1191 __ALIGN_SIZE+0x191 rax 0xffff80000093b000 r8 0xffff8000211a0ee0 r9 0 r10 0x92f33cb3aec98545 r11 0x3851254a13d4c6be r12 0x3000000008 r13 0xffff8000211a0f20 r14 0x100 r15 0xffffffff81cd516a apollo_udma100_tim+0xed43 rip 0xffffffff81b0b168 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000211a0f00 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor0) pid=101854 stat=onproc flags process=0 proc=4000000 pri=71, usrpri=71, nice=20 forw=0xffffffffffffffff, list=0xffff800021063c38,0xffffffff81fdbec8 process=0xffff800021064358 user=0xffff80002119c000, vmspace=0xffffff007f124210 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 10376 302426 53466 0 7 0 syz-executor0 *10376 101854 53466 0 7 0x4000000 syz-executor0 92797 180635 1 0 3 0x100083 ttyin getty 15163 148661 0 0 3 0x14200 bored sosplice 84948 39155 35152 0 3 0x82 nanosleep syz-executor1 53466 466735 35152 0 3 0x82 nanosleep syz-executor0 35152 51749 94717 0 3 0x82 thrsleep syz-fuzzer 35152 67799 94717 0 3 0x4000082 nanosleep syz-fuzzer 35152 278325 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 492175 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 158833 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 492281 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 347041 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 198423 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 73520 94717 0 3 0x4000082 kqread syz-fuzzer 35152 469232 94717 0 3 0x4000082 thrsleep syz-fuzzer 35152 481065 94717 0 3 0x4000082 thrsleep syz-fuzzer 94717 405280 35208 0 3 0x10008a pause ksh 35208 490058 69385 0 3 0x92 select sshd 69385 89154 1 0 3 0x80 select sshd 61016 198473 74183 73 3 0x100090 kqread syslogd 74183 288991 1 0 3 0x100082 netio syslogd 5096 81831 1 77 3 0x100090 poll dhclient 6782 170483 1 0 3 0x80 poll dhclient 94224 13977 0 0 3 0x14200 pgzero zerothread 12630 162820 0 0 3 0x14200 aiodoned aiodoned 9530 253864 0 0 3 0x14200 syncer update 33315 25760 0 0 3 0x14200 cleaner cleaner 30721 67702 0 0 3 0x14200 reaper reaper 52760 260135 0 0 3 0x14200 pgdaemon pagedaemon 42132 74213 0 0 3 0x14200 bored crynlk 9657 319760 0 0 3 0x14200 bored crypto 11599 413744 0 0 3 0x40014200 acpi0 acpi0 58902 489138 0 0 3 0x40014200 idle1 63212 339148 0 0 3 0x14200 bored softnet 82752 122760 0 0 3 0x14200 bored systqmp 27061 308950 0 0 3 0x14200 bored systq 68880 390227 0 0 3 0x40014200 bored softclock 41547 248419 0 0 3 0x40014200 idle0 1 7575 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper