panic: malformed IPv4 option passed to ip_optcopy Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 326219 89629 65534 0x10 0 0 syz-executor1 *518074 89629 65534 0x10 0x4000000 1K syz-executor1 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(6159f84e38341c92,ffffff007f1443b0,ffff800000173290) at ip_fragment+0x625 ip_output(aaa88730aef01f54,ffffff006f303230,ffffff006d5d7600,0,ffffff006d5d7600,ffffff007ed00938) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(c9102e83a8777c1f,fbe,ffffff007ed00938,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(e2c9f4585fbcd0d6,ffffff007d319c48,ffff80002111b408,ffff80002111b540,1442,0) at sosend+0x477 sys/kern/uipc_socket.c:513 dofilewritev(b40544200a8da28a,0,a,ffff8000210632d8,ffff80002111b540) at dofilewritev+0x148 sys/kern/sys_generic.c:364 sys_writev(60f16f593f33dfca,790,ffff8000210632d8) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(898e51555afa6c3c) at syscall+0x473 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(898e51555afa6c3c) at syscall+0x473 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,d,0,3,64508104010) at Xsyscall+0x128 end of kernel end trace frame: 0x64770d9f5f0, 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(6159f84e38341c92,ffffff007f1443b0,ffff800000173290) at ip_fragment+0x625 ip_output(aaa88730aef01f54,ffffff006f303230,ffffff006d5d7600,0,ffffff006d5d7600,ffffff007ed00938) at ip_output+0xc8d sys/netinet/ip_output.c:501 udp_output(c9102e83a8777c1f,fbe,ffffff007ed00938,0) at udp_output+0x45a sys/netinet/udp_usrreq.c:1004 sosend(e2c9f4585fbcd0d6,ffffff007d319c48,ffff80002111b408,ffff80002111b540,1442,0) at sosend+0x477 sys/kern/uipc_socket.c:513 dofilewritev(b40544200a8da28a,0,a,ffff8000210632d8,ffff80002111b540) at dofilewritev+0x148 sys/kern/sys_generic.c:364 sys_writev(60f16f593f33dfca,790,ffff8000210632d8) at sys_writev+0xdb sys/kern/sys_generic.c:310 syscall(898e51555afa6c3c) at syscall+0x473 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(898e51555afa6c3c) at syscall+0x473 sys/arch/amd64/amd64/trap.c:583 Xsyscall(6,0,d,0,3,64508104010) at Xsyscall+0x128 end of kernel end trace frame: 0x64770d9f5f0, count: -10 ddb{1}> show registers rdi 0xffffffff81ee5310 kprintf_mutex rsi 0xffffffff810e80d7 db_enter+0x17 rbp 0xffff80002111b030 rbx 0xffff80002111b0d0 rdx 0xffff8000020da000 rcx 0x127f __ALIGN_SIZE+0x27f rax 0xffff8000020da000 r8 0xffff80002111b000 r9 0 r10 0x7f14dcb8186bad73 r11 0xf9715846eb16a61d r12 0x3000000008 r13 0xffff80002111b040 r14 0x100 r15 0xffffffff81c5f925 apollo_udma100_tim+0x10a1d rip 0xffffffff810e80d8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002111b020 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor1) pid=518074 stat=onproc flags process=10 proc=4000000 pri=77, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffff8000210639e0,0xffffffff81faceb8 process=0xffff8000210653c0 user=0xffff800021116000, vmspace=0xffffff0065894530 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 89629 326219 57235 65534 7 0x10 syz-executor1 *89629 518074 57235 65534 7 0x4000010 syz-executor1 57235 34021 24075 65534 3 0x90 nanosleep syz-executor1 24075 235008 40181 0 3 0x82 wait syz-executor1 19008 305261 23350 65534 3 0x90 nanosleep syz-executor0 23350 18606 40181 0 3 0x82 wait syz-executor0 97689 301115 0 0 3 0x14200 bored sosplice 40181 194769 84381 0 3 0x82 thrsleep syz-fuzzer 40181 331186 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 319962 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 450870 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 47285 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 108521 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 292675 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 15535 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 390628 84381 0 3 0x4000082 thrsleep syz-fuzzer 40181 329200 84381 0 3 0x4000082 kqread syz-fuzzer 84381 241296 60917 0 3 0x10008a pause ksh 60917 80666 51253 0 3 0x92 select sshd 88435 387833 1 0 3 0x100083 ttyin getty 51253 171068 1 0 3 0x80 select sshd 34426 238951 62237 73 3 0x100090 kqread syslogd 62237 212503 1 0 3 0x100082 netio syslogd 54344 215939 1 77 3 0x100090 poll dhclient 53616 348464 1 0 3 0x80 poll dhclient 58282 67626 0 0 3 0x14200 pgzero zerothread 40406 424150 0 0 3 0x14200 aiodoned aiodoned 24218 322483 0 0 3 0x14200 syncer update 91999 20889 0 0 3 0x14200 cleaner cleaner 18979 88396 0 0 3 0x14200 reaper reaper 39078 487578 0 0 3 0x14200 pgdaemon pagedaemon 58104 455147 0 0 3 0x14200 bored crynlk 3346 247947 0 0 3 0x14200 bored crypto 9488 439871 0 0 3 0x40014200 acpi0 acpi0 27746 111966 0 0 3 0x40014200 idle1 78609 203693 0 0 3 0x14200 bored softnet 50029 92521 0 0 3 0x14200 bored systqmp 87076 1767 0 0 3 0x14200 bored systq 39226 297145 0 0 3 0x40014200 bored softclock 11953 36936 0 0 3 0x40014200 idle0 1 431578 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper