panic: Data modified on freelist: word 4 of object 0xffff800000d36800 size 0x1c0 previous type free (0x6563 != 0xdead4110) Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *271541 59439 0 0x1006 0 0 ndp db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8276b049) at panic+0x165 sys/kern/subr_prf.c:198 malloc(1c0,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 elf_load_file(ffff8000216fa5a0,ffff80002164f800,ffff80002e887d50,ffff800000dccfc0) at elf_load_file+0x3ca sys/kern/exec_elf.c:321 exec_elf_fixup(ffff8000216fa5a0,ffff80002e887d50) at exec_elf_fixup+0x5d sys/kern/exec_elf.c:825 sys_execve(ffff8000216fa5a0,ffff80002e888130,ffff80002e888180) at sys_execve+0x12e2 sys/kern/kern_exec.c:701 syscall(ffff80002e888200) at syscall+0x4a8 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74dae7cd5560, count: 7 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: Data modified on freelist: word 4 of object 0xffff800000d36800 size 0x1c0 previous type free (0x6563 != 0xdead4110) ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8276b049) at panic+0x165 sys/kern/subr_prf.c:198 malloc(1c0,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 elf_load_file(ffff8000216fa5a0,ffff80002164f800,ffff80002e887d50,ffff800000dccfc0) at elf_load_file+0x3ca sys/kern/exec_elf.c:321 exec_elf_fixup(ffff8000216fa5a0,ffff80002e887d50) at exec_elf_fixup+0x5d sys/kern/exec_elf.c:825 sys_execve(ffff8000216fa5a0,ffff80002e888130,ffff80002e888180) at sys_execve+0x12e2 sys/kern/kern_exec.c:701 syscall(ffff80002e888200) at syscall+0x4a8 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74dae7cd5560, count: -8 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002e887590 rbx 0xffff800000d36800 rdx 0 rcx 0 rax 0xffff8000216fa5a0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x5ca914043d867c3 r11 0xa6ba74c3756108f5 r12 0 r13 0x51 r14 0 r15 0x1 rip 0xffffffff8186aa8c db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff80002e887580 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (ndp) pid=271541 stat=onproc flags process=1006 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000216fb338,0xffffffff82c30948 process=0xffff8000216fc7f0 user=0xffff80002e883000, vmspace=0xfffffd807e5e2458 estcpu=6, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND *59439 271541 45366 0 7 0x1006 ndp 45366 313685 30919 0 3 0x10008a sigsusp sh 30919 360680 26905 0 3 0x82 wait syz-executor.5 44245 426893 90412 0 2 0 syz-executor.4 43649 330409 42093 0 2 0 syz-executor.2 43649 485269 42093 0 2 0x4000000 syz-executor.2 90690 36061 78719 0 2 0 syz-executor.6 66229 66923 69930 0 2 0 syz-executor.0 84573 50097 85178 0 2 0 syz-executor.7 71558 94872 0 0 3 0x14280 nfsidl nfsio 53983 286301 0 0 3 0x14280 nfsidl nfsio 36415 228486 0 0 3 0x14280 nfsidl nfsio 42672 117189 0 0 3 0x14280 nfsidl nfsio 79866 53008 0 0 3 0x14280 nfsidl nfsio 13817 217256 0 0 3 0x14280 nfsidl nfsio 56309 480026 0 0 3 0x14280 nfsidl nfsio 23411 231878 0 0 3 0x14280 nfsidl nfsio 81700 493543 0 0 3 0x14280 nfsidl nfsio 13807 185405 0 0 3 0x14280 nfsidl nfsio 14224 176872 0 0 3 0x14280 nfsidl nfsio 69070 57750 0 0 3 0x14280 nfsidl nfsio 76922 327336 0 0 3 0x14280 nfsidl nfsio 25588 154959 0 0 3 0x14280 nfsidl nfsio 65620 249036 0 0 3 0x14280 nfsidl nfsio 63775 182751 0 0 3 0x14280 nfsidl nfsio 46181 66107 0 0 3 0x14280 nfsidl nfsio 38597 224966 0 0 3 0x14280 nfsidl nfsio 19831 512283 0 0 3 0x14280 nfsidl nfsio 69591 365595 0 0 3 0x14280 nfsidl nfsio 78719 161779 26905 0 2 0x2 syz-executor.6 9479 62124 0 0 3 0x14200 bored sosplice 44171 392619 1 0 3 0x100083 ttyin getty 85178 143167 26905 0 2 0x2 syz-executor.7 4934 286234 26905 0 2 0x2 syz-executor.1 90412 231256 26905 0 2 0x2 syz-executor.4 62646 287474 26905 0 3 0x82 piperd syz-executor.3 42093 489245 26905 0 3 0x82 nanoslp syz-executor.2 69930 421468 26905 0 2 0x482 syz-executor.0 26905 441035 9732 0 3 0x82 wait syz-fuzzer 26905 445682 9732 0 2 0x4000482 syz-fuzzer 26905 284864 9732 0 3 0x4000082 wait syz-fuzzer 26905 425195 9732 0 3 0x4000082 wait syz-fuzzer 26905 305209 9732 0 3 0x4000082 thrsleep syz-fuzzer 26905 159587 9732 0 3 0x4000082 wait syz-fuzzer 26905 519394 9732 0 3 0x4000082 wait syz-fuzzer 26905 92636 9732 0 3 0x4000082 thrsleep syz-fuzzer 26905 233407 9732 0 3 0x4000082 wait syz-fuzzer 26905 189347 9732 0 3 0x4000082 thrsleep syz-fuzzer 26905 277642 9732 0 3 0x4000082 kqread syz-fuzzer 26905 119179 9732 0 3 0x4000082 wait syz-fuzzer 26905 452989 9732 0 3 0x4000082 thrsleep syz-fuzzer 26905 89083 9732 0 3 0x4000082 wait syz-fuzzer 9732 505456 50728 0 3 0x10008a sigsusp ksh 50728 417545 82657 0 3 0x9a kqread sshd 82657 441719 1 0 3 0x88 kqread sshd 48841 5144 52540 73 3 0x1100090 kqread syslogd 52540 280072 1 0 3 0x100082 netio syslogd 91988 243664 1 0 3 0x100080 kqread resolvd 81600 87674 26948 77 3 0x100092 kqread dhcpleased 14926 182200 26948 77 3 0x100092 kqread dhcpleased 26948 350853 1 0 3 0x80 kqread dhcpleased 89418 179450 0 0 3 0x14200 bored smr 71509 349156 0 0 2 0x14200 zerothread 11980 474970 0 0 3 0x14200 aiodoned aiodoned 38543 451998 0 0 3 0x14200 syncer update 45448 232322 0 0 3 0x14200 cleaner cleaner 19 77700 0 0 3 0x14200 reaper reaper 29321 161062 0 0 3 0x14200 pgdaemon pagedaemon 11982 251427 0 0 3 0x14200 bored viomb 55970 300642 0 0 3 0x40014200 acpi0 acpi0 50533 446289 0 0 3 0x14200 bored softnet3 16102 222747 0 0 3 0x14200 bored softnet2 15435 449881 0 0 3 0x14200 bored softnet1 66410 134150 0 0 3 0x14200 bored softnet0 87602 344733 0 0 3 0x14200 bored systqmp 32645 47734 0 0 3 0x14200 bored systq 50430 486881 0 0 3 0x40014200 bored softclock 95386 217267 0 0 3 0x40014200 idle0 1 120897 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10169 6465K 7341K 78643K 18916 0 pcb 13 9K 10K 78643K 96 0 rtable 232 6K 6K 78643K 454 0 pf 29 8K 9K 78643K 87 0 ifaddr 43 11K 12K 78643K 80 0 ifgroup 50 2K 2K 78643K 128 0 sysctl 2 0K 0K 78643K 2 0 counters 28 17K 17K 78643K 53 0 ioctlops 0 0K 2K 78643K 45 0 iov 0 0K 16K 78643K 186 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1403 88K 88K 78643K 3073 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 38 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 94 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 17 61K 73K 78643K 1754 0 sigio 0 0K 0K 78643K 17 0 proc 58 59K 75K 78643K 599 0 subproc 104 6K 6K 78643K 130 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 60 0 in_multi 99 7K 7K 78643K 138 0 ether_multi 1 0K 0K 78643K 1 0 mrt 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 61 281K 281K 78643K 61 0 exec 1 0K 1K 78643K 502 0 pfkey data 0 0K 0K 78643K 4 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 64K 78643K 10 0 UVM amap 310 87K 89K 78643K 18530 0 UVM aobj 131 4K 4K 78643K 131 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 53 0 NDP 13 0K 1K 78643K 56 0 temp 75 5860K 5924K 78643K 15497 0 kqueue 12 18K 30K 78643K 312 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 90 0 87 2 1 1 2 0 8 0 rtentry 112 134 0 25 4 0 4 4 0 8 0 unpcb 144 1658 0 1645 23 20 3 6 0 8 2 syncache 296 4 0 4 1 1 0 1 0 8 0 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 166 0 166 2 2 0 1 0 8 0 tcpcb 808 253 0 249 11 9 2 7 0 8 1 arp 88 22 0 4 1 0 1 1 0 8 0 ipq 40 2 0 2 2 2 0 1 0 8 0 ipqe 40 7 0 7 2 2 0 1 0 8 0 inpcb 336 623 0 616 17 15 2 7 0 8 1 nd6 104 31 0 8 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 1 0 1 0 8 0 kcovpl 48 10 0 2 1 0 1 1 0 8 0 ppxss 1160 15 0 15 4 4 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 559 0 102 29 0 29 29 0 8 0 art_table 32 560 0 102 4 0 4 4 0 8 0 art_node 16 133 0 34 1 0 1 1 0 8 0 sysvmsgpl 40 19 0 13 1 0 1 1 0 8 0 semupl 112 7 0 7 3 3 0 1 0 8 0 semapl 112 92 0 82 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 3935 0 2496 91 0 91 91 0 8 0 ffsino 240 3935 0 2496 85 0 85 85 0 8 0 nchpl 144 6607 0 6120 63 42 21 63 0 8 0 uvmvnodes 80 5298 0 0 109 0 109 109 0 8 0 vnodes 216 5298 0 0 295 0 295 295 0 8 0 namei 1024 22334 0 22333 6 5 1 3 0 8 0 kstatmem 264 72 0 50 2 0 2 2 0 8 0 scxspl 216 23423 0 23423 12 11 1 8 0 8 1 plimitpl 152 196 0 181 1 0 1 1 0 8 0 sigapl 424 2089 0 2024 10 2 8 8 0 8 0 futexpl 64 15051 0 15051 3 2 1 1 0 8 1 knotepl 120 19478 0 19396 4 1 3 4 0 8 0 kqueuepl 184 454 0 446 5 4 1 3 0 8 0 pipepl 288 1094 0 1066 17 11 6 7 0 8 3 fdescpl 432 2032 0 2004 4 0 4 4 0 8 0 filepl 120 13499 0 13265 33 20 13 14 0 8 5 lockfpl 104 1482 0 1480 4 3 1 2 0 8 0 lockfspl 48 734 0 732 1 0 1 1 0 8 0 sessionpl 144 26 0 10 1 0 1 1 0 8 0 pgrppl 48 26 0 10 1 0 1 1 0 8 0 ucredpl 104 2338 0 2328 1 0 1 1 0 8 0 zombiepl 144 2024 0 2024 1 0 1 1 0 8 1 processpl 1008 2089 0 2024 12 3 9 9 0 8 0 procpl 696 4744 0 4665 14 5 9 9 0 8 1 sosppl 168 6 0 6 2 2 0 1 0 8 0 sockpl 456 2512 0 2489 106 95 11 24 0 8 8 mcl64k 65536 51 0 51 6 6 0 1 0 8 0 mcl16k 16384 22 0 22 6 6 0 1 0 8 0 mcl12k 12288 56 0 56 6 5 1 1 0 8 1 mcl9k 9216 41 0 41 3 3 0 1 0 8 0 mcl8k 8192 126 0 126 8 7 1 1 0 8 1 mcl4k 4096 169 0 169 6 5 1 1 0 8 1 mcl2k2 2112 16 0 16 7 6 1 1 0 8 1 mcl2k 2048 60602 0 60499 39 25 14 30 0 8 0 mtagpl 96 1953 0 752 37 1 36 36 0 8 1 mbufpl 256 108732 0 107380 146 44 102 102 0 8 4 bufpl 288 7237 0 849 457 0 457 457 0 8 0 anonpl 24 366412 0 356629 124 23 101 103 0 188 20 amapchunkpl 152 60329 0 59623 56 12 44 45 0 158 9 amappl16 200 9452 0 9133 42 16 26 30 0 8 8 amappl15 192 7 0 7 1 1 0 1 0 8 0 amappl14 184 162 0 149 2 1 1 2 0 8 0 amappl13 176 19 0 18 1 0 1 1 0 8 0 amappl12 168 2684 0 2658 2 0 2 2 0 8 0 amappl11 160 52 0 42 1 0 1 1 0 8 0 amappl10 152 26 0 17 1 0 1 1 0 8 0 amappl9 144 185 0 183 2 1 1 2 0 8 0 amappl8 136 236 0 165 3 0 3 3 0 8 0 amappl7 128 65 0 53 1 0 1 1 0 8 0 amappl6 120 263 0 246 2 1 1 2 0 8 0 amappl5 112 182 0 175 1 0 1 1 0 8 0 amappl4 104 605 0 572 2 1 1 2 0 8 0 amappl3 96 11998 0 11939 3 0 3 3 0 8 0 amappl2 88 2254 0 2200 4 2 2 3 0 8 0 amappl1 80 15695 0 15198 22 11 11 22 0 8 0 amappl 88 17959 0 17773 6 0 6 6 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 130 0 0 3 0 3 3 0 8 0 uaddrrnd 24 2032 0 2004 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2032 0 2004 1 0 1 1 0 8 0 vmmpekpl 168 23246 0 23194 3 0 3 3 0 8 0 vmmpepl 168 140201 0 138172 161 49 112 112 0 357 15 vmsppl 368 2031 0 2004 3 0 3 3 0 8 0 rwobjpl 24 46672 0 39954 43 1 42 42 0 8 0 pdppl 4096 4070 0 4008 182 120 62 68 0 8 0 pvpl 32 836839 0 822359 406 208 198 334 0 265 55 pmappl 216 2031 0 2004 2 0 2 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1116 0 255 25 0 25 25 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8276b049) at panic+0x165 sys/kern/subr_prf.c:198 malloc(1c0,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 elf_load_file(ffff8000216fa5a0,ffff80002164f800,ffff80002e887d50,ffff800000dccfc0) at elf_load_file+0x3ca sys/kern/exec_elf.c:321 exec_elf_fixup(ffff8000216fa5a0,ffff80002e887d50) at exec_elf_fixup+0x5d sys/kern/exec_elf.c:825 sys_execve(ffff8000216fa5a0,ffff80002e888130,ffff80002e888180) at sys_execve+0x12e2 sys/kern/kern_exec.c:701 syscall(ffff80002e888200) at syscall+0x4a8 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74dae7cd5560, count: -8 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8276b049) at panic+0x165 sys/kern/subr_prf.c:198 malloc(1c0,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 elf_load_file(ffff8000216fa5a0,ffff80002164f800,ffff80002e887d50,ffff800000dccfc0) at elf_load_file+0x3ca sys/kern/exec_elf.c:321 exec_elf_fixup(ffff8000216fa5a0,ffff80002e887d50) at exec_elf_fixup+0x5d sys/kern/exec_elf.c:825 sys_execve(ffff8000216fa5a0,ffff80002e888130,ffff80002e888180) at sys_execve+0x12e2 sys/kern/kern_exec.c:701 syscall(ffff80002e888200) at syscall+0x4a8 sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x74dae7cd5560, count: -8