panic: malformed IPv4 option passed to ip_optcopy Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *282165 85219 65534 0x10 0x4000000 1K syz-executor1 320835 88499 65534 0x10 0 0 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(69902b26a031a31a,ffffff007f143db0,ffff800000173290) at ip_fragment+0x625 ip_output(8d8865e4618b7516,ffffff006f3068c0,ffffff007f143e00,0,ffffff007f143e00,ffffff006f307a80) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(29e9ded8d6c5bbc2,11af,ffffff006f307a80,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(c45a9f2fefe64f98,ffffff0064d63620,ffff800021144e58,ffff800021144f90,1251,0) at sosend+0x477 sys/kern/uipc_socket.c:513 dofilewritev(600a130969a780f6,0,5,ffff800021044260,ffff800021144f90) at dofilewritev+0x148 sys/kern/sys_generic.c:364 sys_writev(b0480616118d79fb,790,ffff800021044260) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(86616c4b61a50c75) at syscall+0x473 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(86616c4b61a50c75) at syscall+0x473 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,d,0,3,357c5395010) at Xsyscall+0x128 end of kernel end trace frame: 0x35a9f2a44d0, 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{1}> ddb{1}> set $lines = 0 ddb{1}> show panic malformed IPv4 option passed to ip_optcopy ddb{1}> 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(69902b26a031a31a,ffffff007f143db0,ffff800000173290) at ip_fragment+0x625 ip_output(8d8865e4618b7516,ffffff006f3068c0,ffffff007f143e00,0,ffffff007f143e00,ffffff006f307a80) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(29e9ded8d6c5bbc2,11af,ffffff006f307a80,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(c45a9f2fefe64f98,ffffff0064d63620,ffff800021144e58,ffff800021144f90,1251,0) at sosend+0x477 sys/kern/uipc_socket.c:513 dofilewritev(600a130969a780f6,0,5,ffff800021044260,ffff800021144f90) at dofilewritev+0x148 sys/kern/sys_generic.c:364 sys_writev(b0480616118d79fb,790,ffff800021044260) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(86616c4b61a50c75) at syscall+0x473 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(86616c4b61a50c75) at syscall+0x473 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,d,0,3,357c5395010) at Xsyscall+0x128 end of kernel end trace frame: 0x35a9f2a44d0, count: -10 ddb{1}> show registers rdi 0xffffffff81f14858 kprintf_mutex rsi 0xffffffff81a305f7 db_enter+0x17 rbp 0xffff800021144a80 rbx 0xffff800021144b20 rdx 0xffff8000012d9000 rcx 0x1468 __ALIGN_SIZE+0x468 rax 0xffff8000012d9000 r8 0xffff800021144a50 r9 0 r10 0xcf71d536298b9b7a r11 0xbe065223f20e2e8f r12 0x3000000008 r13 0xffff800021144a90 r14 0x100 r15 0xffffffff81c5fd6d apollo_udma100_tim+0x13afa rip 0xffffffff81a305f8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800021144a70 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor1) pid=282165 stat=onproc flags process=10 proc=4000000 pri=55, usrpri=55, nice=20 forw=0xffffffffffffffff, list=0xffff800021045070,0xffffffff81faa5b8 process=0xffff800021064010 user=0xffff800021140000, vmspace=0xffffff007bf0c630 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 85219 110949 83977 65534 2 0x10 syz-executor1 *85219 282165 83977 65534 7 0x4000010 syz-executor1 88499 320835 48498 65534 7 0x10 syz-executor0 88499 226639 48498 65534 3 0x4000090 kqread syz-executor0 88499 477406 48498 65534 3 0x4000090 kqread syz-executor0 83977 473351 78829 65534 3 0x90 nanosleep syz-executor1 78829 327938 94563 0 3 0x82 wait syz-executor1 48498 7170 62166 65534 3 0x90 nanosleep syz-executor0 62166 388924 94563 0 3 0x82 wait syz-executor0 56394 116326 0 0 3 0x14200 bored sosplice 94563 286826 54361 0 3 0x82 kqread syz-fuzzer 94563 304628 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 434341 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 39354 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 268617 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 365001 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 54657 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 159958 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 177884 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 137387 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 376125 54361 0 3 0x4000082 thrsleep syz-fuzzer 94563 354065 54361 0 3 0x4000082 thrsleep syz-fuzzer 54361 289550 85918 0 3 0x10008a pause ksh 85918 61970 90545 0 3 0x92 select sshd 27134 236098 1 0 3 0x100083 ttyin getty 90545 259105 1 0 3 0x80 select sshd 55491 188914 75337 73 3 0x100090 kqread syslogd 75337 83131 1 0 3 0x100082 netio syslogd 53545 137345 1 77 3 0x100090 poll dhclient 10891 388786 1 0 3 0x80 poll dhclient 80251 54946 0 0 2 0x14200 zerothread 40075 122980 0 0 3 0x14200 aiodoned aiodoned 25419 264133 0 0 3 0x14200 syncer update 82503 141366 0 0 3 0x14200 cleaner cleaner 12168 40387 0 0 3 0x14200 reaper reaper 20558 456869 0 0 3 0x14200 pgdaemon pagedaemon 80989 334721 0 0 3 0x14200 bored crynlk 43944 93231 0 0 3 0x14200 bored crypto 30416 231112 0 0 3 0x40014200 acpi0 acpi0 68735 352099 0 0 3 0x40014200 idle1 83223 498400 0 0 3 0x14200 bored softnet 18215 336397 0 0 3 0x14200 bored systqmp 16098 513550 0 0 3 0x14200 bored systq 70244 313427 0 0 3 0x40014200 bored softclock 27980 464713 0 0 3 0x40014200 idle0 1 375324 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper