panic: malformed IPv4 option passed to ip_optcopy Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *277584 25119 32767 0x10 0x4000000 0K syz-executor1 122689 28213 32767 0x10 0 1 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(57da4b5b0ad87fac,ffffff006522e1b0,ffff800000173290) at ip_fragment+0x625 ip_output(3882eee60832e82b,ffffff006f4a9af0,ffffff007f143500,0,ffffff007f143500,ffffff006e8cfa88) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(469b8f562e275a8,134e,ffffff006e8cfa88,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(2ca99141276883de,ffffff0079c0f540,ffff80002118f938,10b2,ffff80002118fa70,0) at sosend+0x47a sys/kern/uipc_socket.c:513 dofilewritev(e1ceaeb664be36d8,0,2,ffff80002108b080,ffff80002118fa70) at dofilewritev+0x14b sys/kern/sys_generic.c:364 sys_writev(5406f6c50ff0d856,790,ffff80002108b080) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(c96445a416163a5) at syscall+0x496 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(c96445a416163a5) at syscall+0x496 sys/arch/amd64/amd64/trap.c:583 Xsyscall(0,0,d,0,3,c0842103010) at Xsyscall+0x128 end of kernel end trace frame: 0xc0a74f3cc30, 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(57da4b5b0ad87fac,ffffff006522e1b0,ffff800000173290) at ip_fragment+0x625 ip_output(3882eee60832e82b,ffffff006f4a9af0,ffffff007f143500,0,ffffff007f143500,ffffff006e8cfa88) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(469b8f562e275a8,134e,ffffff006e8cfa88,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(2ca99141276883de,ffffff0079c0f540,ffff80002118f938,10b2,ffff80002118fa70,0) at sosend+0x47a sys/kern/uipc_socket.c:513 dofilewritev(e1ceaeb664be36d8,0,2,ffff80002108b080,ffff80002118fa70) at dofilewritev+0x14b sys/kern/sys_generic.c:364 sys_writev(5406f6c50ff0d856,790,ffff80002108b080) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(c96445a416163a5) at syscall+0x496 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(c96445a416163a5) at syscall+0x496 sys/arch/amd64/amd64/trap.c:583 Xsyscall(0,0,d,0,3,c0842103010) at Xsyscall+0x128 end of kernel end trace frame: 0xc0a74f3cc30, count: -10 ddb{0}> show registers rdi 0xffffffff81f00128 kprintf_mutex rsi 0xffffffff81150e07 db_enter+0x17 rbp 0xffff80002118f560 rbx 0xffff80002118f600 rdx 0xffff80000233d000 rcx 0x1336 __ALIGN_SIZE+0x336 rax 0xffff80000233d000 r8 0xffff80002118f530 r9 0 r10 0xfb9a3e2d9dcc7d85 r11 0xfb96470ae35f10c2 r12 0x3000000008 r13 0xffff80002118f570 r14 0x100 r15 0xffffffff81cd528d apollo_udma100_tim+0xde73 rip 0xffffffff81150e08 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002118f550 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor1) pid=277584 stat=onproc flags process=10 proc=4000000 pri=69, usrpri=69, nice=20 forw=0xffffffffffffffff, list=0xffff80002108a4c8,0xffffffff81f8d720 process=0xffff800021064d30 user=0xffff80002118a000, vmspace=0xffffff006728a538 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 25119 380744 43485 32767 2 0x10 syz-executor1 *25119 277584 43485 32767 7 0x4000010 syz-executor1 28213 122689 37253 32767 7 0x10 syz-executor0 28213 132500 37253 32767 3 0x4000090 netio syz-executor0 37253 507627 40065 32767 3 0x90 nanosleep syz-executor0 40065 201262 14593 0 3 0x82 wait syz-executor0 43485 133675 86606 32767 3 0x90 nanosleep syz-executor1 86606 58913 14593 0 3 0x82 wait syz-executor1 8400 464274 0 0 3 0x14200 bored sosplice 14593 122381 57230 0 3 0x82 thrsleep syz-fuzzer 14593 260595 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 80026 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 202744 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 502726 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 133959 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 361384 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 523519 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 59267 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 473368 57230 0 3 0x4000082 thrsleep syz-fuzzer 14593 255842 57230 0 3 0x4000082 kqread syz-fuzzer 14593 349320 57230 0 3 0x4000082 thrsleep syz-fuzzer 57230 373806 48179 0 3 0x10008a pause ksh 48179 152481 29087 0 3 0x92 select sshd 40212 35873 1 0 3 0x100083 ttyin getty 29087 3860 1 0 3 0x80 select sshd 42494 228527 73031 73 3 0x100090 kqread syslogd 73031 107309 1 0 3 0x100082 netio syslogd 29166 362110 1 77 3 0x100090 poll dhclient 3692 103782 1 0 3 0x80 poll dhclient 82736 65985 0 0 2 0x14200 zerothread 11414 283102 0 0 3 0x14200 aiodoned aiodoned 59650 364999 0 0 3 0x14200 syncer update 65169 373356 0 0 3 0x14200 cleaner cleaner 95757 96667 0 0 3 0x14200 reaper reaper 49518 103402 0 0 3 0x14200 pgdaemon pagedaemon 92764 149 0 0 3 0x14200 bored crynlk 15676 331444 0 0 3 0x14200 bored crypto 6927 346566 0 0 3 0x40014200 acpi0 acpi0 56619 35331 0 0 3 0x40014200 idle1 33524 267667 0 0 3 0x14200 bored softnet 23372 165619 0 0 3 0x14200 bored systqmp 56584 157005 0 0 3 0x14200 bored systq 86368 77986 0 0 3 0x40014200 bored softclock 47585 392029 0 0 3 0x40014200 idle0 1 425431 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper