panic: Data modified on freelist: word 4 of object 0xffff800000ddd200 size 0x200 previous type counters (0x6563 != 0xdeafbead) Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *289095 62391 0 0 0x4000000 0 syz-executor.3 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82575b2f) at panic+0x161 sys/kern/subr_prf.c:198 malloc(200,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 vndsetcred sys/dev/vnd.c:681 [inline] vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 sys/dev/vnd.c:487 VOP_IOCTL(fffffd806eb47c28,c0384600,ffff80002cf954f0,1,fffffd807f7d7820,ffff80002175f268) at VOP_IOCTL+0x8d sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806834a2e8,c0384600,ffff80002cf954f0,ffff80002175f268) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:525 sys_ioctl(ffff80002175f268,ffff80002cf95608,ffff80002cf95650) at sys_ioctl+0x49e syscall(ffff80002cf956d0) at syscall+0x446 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xac283d81f60, count: 6 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 0xffff800000ddd200 size 0x200 previous type counters (0x6563 != 0xdeafbead) ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82575b2f) at panic+0x161 sys/kern/subr_prf.c:198 malloc(200,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 vndsetcred sys/dev/vnd.c:681 [inline] vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 sys/dev/vnd.c:487 VOP_IOCTL(fffffd806eb47c28,c0384600,ffff80002cf954f0,1,fffffd807f7d7820,ffff80002175f268) at VOP_IOCTL+0x8d sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806834a2e8,c0384600,ffff80002cf954f0,ffff80002175f268) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:525 sys_ioctl(ffff80002175f268,ffff80002cf95608,ffff80002cf95650) at sys_ioctl+0x49e syscall(ffff80002cf956d0) at syscall+0x446 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xac283d81f60, count: -9 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002cf94b30 rbx 0xffff800000ddd200 rdx 0xffff800000bc0d40 rcx 0 rax 0xffff80002175f268 r8 0x101010101010101 r9 0x8080808080808080 r10 0x8b463ffffd1efac5 r11 0x325ded9180f6a5cf r12 0 r13 0x51 r14 0 r15 0x1 rip 0xffffffff821192f8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002cf94b20 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.3) pid=289095 stat=onproc flags process=0 proc=4000000 pri=51, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff80002175e7e8,0xffff80002178a7f8 process=0xffff800028056438 user=0xffff80002cf90000, vmspace=0xfffffd8068af4000 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 60690 143058 62962 0 3 0x80 fsleep syz-executor.6 60690 487984 62962 0 2 0x4000000 syz-executor.6 62391 366346 65625 0 3 0x80 fsleep syz-executor.3 *62391 289095 65625 0 7 0x4000000 syz-executor.3 33929 141480 60740 0 3 0x80 nanoslp syz-executor.4 33929 102410 60740 0 2 0x4000000 syz-executor.4 33929 480469 60740 0 2 0x4000000 syz-executor.4 33929 284300 60740 0 2 0x4000000 syz-executor.4 65222 288160 12389 0 3 0x80 fsleep syz-executor.0 65222 132853 12389 0 2 0x4000000 syz-executor.0 30387 202776 60101 0 2 0 syz-executor.1 30387 160472 60101 0 3 0x4000080 fsleep syz-executor.1 30387 253659 60101 0 3 0x4000080 fsleep syz-executor.1 30387 40252 60101 0 3 0x4000080 fsleep syz-executor.1 36855 368061 30688 0 3 0x80 fsleep syz-executor.5 36855 118695 30688 0 3 0x4000080 kqpoll syz-executor.5 30688 516124 85904 0 3 0x82 nanoslp syz-executor.5 76466 421986 85904 0 3 0x82 nanoslp syz-executor.7 88420 378629 85904 0 3 0x2 biowait syz-executor.2 60101 124103 85904 0 3 0x82 nanoslp syz-executor.1 12389 63099 85904 0 3 0x82 nanoslp syz-executor.0 60740 521063 85904 0 3 0x82 nanoslp syz-executor.4 65625 489341 85904 0 3 0x82 nanoslp syz-executor.3 62962 243178 85904 0 3 0x82 nanoslp syz-executor.6 51507 197218 0 0 3 0x14200 bored sosplice 50152 494984 1 0 3 0x100083 ttyin getty 6651 124582 0 0 3 0x14280 nfsidl nfsio 29220 7441 0 0 3 0x14280 nfsidl nfsio 87037 212228 0 0 3 0x14280 nfsidl nfsio 81190 476802 0 0 3 0x14280 nfsidl nfsio 72860 61216 0 0 3 0x14280 nfsidl nfsio 91960 118933 0 0 3 0x14280 nfsidl nfsio 44742 21266 0 0 3 0x14280 nfsidl nfsio 9364 483016 0 0 3 0x14280 nfsidl nfsio 77435 107791 0 0 3 0x14280 nfsidl nfsio 87451 162888 0 0 3 0x14280 nfsidl nfsio 93898 7367 0 0 3 0x14280 nfsidl nfsio 17957 363977 0 0 3 0x14280 nfsidl nfsio 1596 41103 0 0 3 0x14280 nfsidl nfsio 4734 62142 0 0 3 0x14280 nfsidl nfsio 14860 177405 0 0 3 0x14280 nfsidl nfsio 12496 23468 0 0 3 0x14280 nfsidl nfsio 95028 257022 0 0 3 0x14280 nfsidl nfsio 34584 374593 0 0 3 0x14280 nfsidl nfsio 55975 138085 0 0 3 0x14280 nfsidl nfsio 67474 86447 0 0 3 0x14280 nfsidl nfsio 85904 270577 19255 0 3 0x82 kqread syz-fuzzer 85904 120240 19255 0 3 0x4000082 nanoslp syz-fuzzer 85904 270455 19255 0 3 0x4000082 thrsleep syz-fuzzer 85904 488486 19255 0 3 0x4000082 thrsleep syz-fuzzer 85904 192815 19255 0 3 0x4000082 wait syz-fuzzer 85904 361746 19255 0 3 0x4000082 thrsleep syz-fuzzer 85904 393558 19255 0 3 0x4000082 wait syz-fuzzer 85904 44931 19255 0 3 0x4000082 wait syz-fuzzer 85904 1795 19255 0 3 0x4000082 thrsleep syz-fuzzer 85904 169442 19255 0 3 0x4000082 wait syz-fuzzer 85904 168835 19255 0 3 0x4000082 wait syz-fuzzer 85904 405863 19255 0 3 0x4000082 wait syz-fuzzer 85904 242927 19255 0 3 0x4000082 wait syz-fuzzer 85904 201064 19255 0 3 0x4000082 wait syz-fuzzer 19255 13258 70622 0 3 0x10008a sigsusp ksh 70622 77076 76736 0 3 0x9a kqread sshd 76736 43874 1 0 3 0x88 kqread sshd 9533 285820 97805 73 3 0x1100090 kqread syslogd 97805 272440 1 0 3 0x100082 netio syslogd 42415 9287 1 0 3 0x100080 kqread resolvd 21925 95156 25855 77 3 0x100092 kqread dhcpleased 59264 231342 25855 77 3 0x100092 kqread dhcpleased 25855 141463 1 0 3 0x80 kqread dhcpleased 86250 391152 0 0 3 0x14200 bored smr 57668 198180 0 0 2 0x14200 zerothread 90868 159343 0 0 3 0x14200 aiodoned aiodoned 39032 141454 0 0 3 0x14200 syncer update 31588 521457 0 0 3 0x14200 cleaner cleaner 94878 356269 0 0 3 0x14200 reaper reaper 41660 233880 0 0 3 0x14200 pgdaemon pagedaemon 52520 118980 0 0 3 0x14200 bored viomb 6821 94100 0 0 3 0x40014200 acpi0 acpi0 5750 454366 0 0 3 0x14200 bored softnet 37742 308602 0 0 3 0x14200 bored softnet 41596 371275 0 0 3 0x14200 bored softnet 51175 473393 0 0 3 0x14200 bored softnet 92279 373678 0 0 3 0x14200 bored systqmp 86007 419998 0 0 3 0x14200 bored systq 72956 325470 0 0 3 0x40014200 bored softclock 84934 141475 0 0 3 0x40014200 idle0 1 133742 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 10228 6485K 7859K 78643K 41926 0 pcb 13 18K 21K 78643K 1459 0 rtable 263 22K 26K 78643K 3508 0 ifaddr 140 32K 34K 78643K 1532 0 sysctl 2 0K 0K 78643K 2 0 counters 27 17K 17K 78643K 322 0 ioctlops 0 0K 4K 78643K 2590 0 iov 0 0K 20K 78643K 949 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1538 96K 96K 78643K 14757 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 3 5K 5K 78643K 73 0 VM map 2 0K 0K 78643K 2 0 sem 23 3K 3K 78643K 988 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 16 57K 77K 78643K 11023 0 sigio 0 0K 0K 78643K 88 0 proc 59 59K 75K 78643K 2179 0 subproc 104 6K 7K 78643K 715 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 286 0 in_multi 103 6K 7K 78643K 863 0 ether_multi 1 0K 0K 78643K 65 0 mrt 1 0K 0K 78643K 38 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 241 1076K 1076K 78643K 241 0 exec 0 0K 1K 78643K 2116 0 pfkey data 0 0K 0K 78643K 74 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 436 759K 759K 78643K 73432 0 UVM aobj 131 5K 5K 78643K 137 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 346 0 NDP 15 0K 1K 78643K 314 0 temp 140 4731K 5754K 78643K 187717 0 kqueue 12 18K 26K 78643K 678 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 120 652 0 649 9 8 1 3 0 8 0 rtentry 112 786 0 684 4 0 4 4 0 8 0 unpcb 144 8458 0 8445 101 100 1 6 0 8 0 syncache 296 36 0 36 11 11 0 1 0 8 0 tcpqe 32 59 0 59 6 6 0 1 0 8 0 tcpcb 776 2415 0 2411 121 120 1 14 0 8 0 arp 88 116 0 97 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 7455 0 7446 180 179 1 12 0 8 0 ip6q 72 6 0 6 2 2 0 1 0 8 0 ip6af 40 12 0 12 2 2 0 1 0 8 0 nd6 48 182 0 158 1 0 1 1 0 8 0 pkpcb 40 43 0 43 9 9 0 1 0 8 0 kcovpl 48 55 0 47 1 0 1 1 0 8 0 mppekey 1024 5 0 5 2 2 0 1 0 8 0 ppxss 1160 156 0 156 20 20 0 1 0 8 0 pppxif 1608 112 0 112 15 15 0 1 0 8 0 pfstscr 40 14 0 13 2 1 1 1 0 8 0 pfrktable 1344 516 0 507 11 10 1 2 0 8 0 pfanchor 1280 955 55 443 53 10 43 43 0 8 0 pftag 88 12 0 9 3 2 1 1 0 8 0 pfqueue 264 7 0 7 2 2 0 1 0 8 0 pfstitem 24 2 0 0 1 0 1 1 0 8 0 pfstkey 120 20 0 18 2 1 1 1 0 8 0 pfstate 336 10 0 9 2 1 1 1 0 8 0 pfrule 1360 427 0 389 7 3 4 4 0 8 0 rttmr 136 12 0 12 2 2 0 1 0 8 0 art_heap8 4096 5 0 4 5 4 1 2 0 8 0 art_heap4 256 3604 0 3143 47 18 29 30 0 8 0 art_table 32 3609 0 3147 5 1 4 4 0 8 0 art_node 16 785 0 694 1 0 1 1 0 8 0 sysvmsgpl 40 9 0 3 1 0 1 1 0 8 0 semapl 112 984 0 963 1 0 1 1 0 8 0 shmpl 112 134 0 6 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 19788 0 18301 94 0 94 94 0 8 0 ffsino 240 19788 0 18301 88 0 88 88 0 8 0 nchpl 144 34730 0 34169 63 40 23 63 0 8 0 rtmask 32 6 0 6 2 2 0 1 0 8 0 uvmvnodes 80 6378 0 0 131 0 131 131 0 8 0 vnodes 216 6378 0 0 355 0 355 355 0 8 0 namei 1024 138245 0 138245 10 8 2 2 0 8 2 vcpupl 2048 112 0 0 14 0 14 14 0 8 0 vmpool 536 138 0 26 9 1 8 8 0 8 0 pfiaddrpl 120 161 0 142 5 4 1 1 0 8 0 kstatmem 264 380 0 350 3 0 3 3 0 8 0 scsiplug 72 6 0 6 2 2 0 1 0 8 0 scxspl 216 95975 0 95974 25 24 1 8 0 8 0 plimitpl 152 1528 0 1513 1 0 1 1 0 8 0 sigapl 424 11241 0 11176 8 0 8 8 0 8 0 futexpl 64 107171 0 107164 5 4 1 1 0 8 0 knotepl 120 124383 0 124303 58 54 4 11 0 8 0 kqueuepl 184 1687 0 1678 25 24 1 4 0 8 0 pipepl 288 1507 0 1479 22 19 3 7 0 8 0 fdescpl 432 11203 0 11176 4 0 4 4 0 8 0 filepl 120 86094 0 85856 172 160 12 17 0 8 4 lockfpl 104 3716 0 3714 5 4 1 2 0 8 0 lockfspl 48 1627 0 1625 1 0 1 1 0 8 0 sessionpl 144 71 0 55 1 0 1 1 0 8 0 pgrppl 48 89 0 73 1 0 1 1 0 8 0 ucredpl 104 23958 0 23946 1 0 1 1 0 8 0 zombiepl 144 11177 0 11176 4 3 1 1 0 8 0 processpl 1000 11241 0 11176 11 2 9 9 0 8 0 procpl 672 31168 0 31080 26 17 9 10 0 8 0 sosppl 168 83 0 83 12 12 0 1 0 8 0 sockpl 456 16608 0 16585 496 492 4 25 0 8 1 mcl64k 65536 1175 0 1175 20 20 0 1 0 8 0 mcl16k 16384 243 0 243 34 33 1 1 0 8 1 mcl12k 12288 382 0 382 38 37 1 1 0 8 1 mcl9k 9216 170 0 170 35 35 0 1 0 8 0 mcl8k 8192 696 0 696 36 36 0 1 0 8 0 mcl4k 4096 893 0 893 17 16 1 1 0 8 1 mcl2k2 2112 97 0 97 37 37 0 1 0 8 0 mcl2k 2048 103211 0 103134 55 44 11 30 0 8 0 mtagpl 96 1900 0 1422 17 5 12 12 0 8 0 mbufpl 256 271907 0 271235 603 559 44 77 0 8 0 bufpl 288 23152 0 16745 458 0 458 458 0 8 0 anonpl 24 2179325 0 2162028 301 189 112 174 0 188 0 amapchunkpl 152 207656 0 206928 114 82 32 58 0 158 0 amappl16 200 19780 0 19182 78 45 33 45 0 8 0 amappl15 192 4 0 4 1 1 0 1 0 8 0 amappl14 184 331 0 318 2 0 2 2 0 8 0 amappl13 176 11 0 10 1 0 1 1 0 8 0 amappl12 168 968 0 963 1 0 1 1 0 8 0 amappl11 160 41 0 31 1 0 1 1 0 8 0 amappl10 152 87 0 75 1 0 1 1 0 8 0 amappl9 144 1108 0 1104 1 0 1 1 0 8 0 amappl8 136 494 0 410 3 0 3 3 0 8 0 amappl7 128 93 0 75 1 0 1 1 0 8 0 amappl6 120 861 0 844 2 1 1 2 0 8 0 amappl5 112 930 0 922 1 0 1 1 0 8 0 amappl4 104 1359 0 1331 2 0 2 2 0 8 0 amappl3 96 32218 0 32165 2 0 2 2 0 8 0 amappl2 88 11983 0 11912 3 1 2 3 0 8 0 amappl1 80 251956 0 251246 23 7 16 21 0 8 0 amappl 88 72595 0 72358 7 1 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 72 136 0 6 3 0 3 3 0 8 0 uaddrrnd 24 11341 0 11202 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 11341 0 11202 1 0 1 1 0 8 0 vmmpekpl 168 83584 0 83507 4 0 4 4 0 8 0 vmmpepl 168 1030098 0 1027175 407 270 137 161 0 357 0 vmsppl 272 11340 0 11202 13 3 10 10 0 8 0 rwobjpl 24 269248 0 260958 58 7 51 52 0 8 0 pdppl 4096 22688 0 22516 999 823 176 176 0 8 4 pvpl 32 4320603 0 4297537 580 386 194 311 0 265 0 pmappl 216 11340 0 11202 8 0 8 8 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 2712 0 1770 28 0 28 28 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82575b2f) at panic+0x161 sys/kern/subr_prf.c:198 malloc(200,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 vndsetcred sys/dev/vnd.c:681 [inline] vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 sys/dev/vnd.c:487 VOP_IOCTL(fffffd806eb47c28,c0384600,ffff80002cf954f0,1,fffffd807f7d7820,ffff80002175f268) at VOP_IOCTL+0x8d sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806834a2e8,c0384600,ffff80002cf954f0,ffff80002175f268) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:525 sys_ioctl(ffff80002175f268,ffff80002cf95608,ffff80002cf95650) at sys_ioctl+0x49e syscall(ffff80002cf956d0) at syscall+0x446 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xac283d81f60, count: -9 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82575b2f) at panic+0x161 sys/kern/subr_prf.c:198 malloc(200,7f,1) at malloc+0xa85 sys/kern/kern_malloc.c:362 vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 vndsetcred sys/dev/vnd.c:681 [inline] vndioctl(2902,c0384600,ffff80002cf954f0,1,ffff80002175f268) at vndioctl+0xb76 sys/dev/vnd.c:487 VOP_IOCTL(fffffd806eb47c28,c0384600,ffff80002cf954f0,1,fffffd807f7d7820,ffff80002175f268) at VOP_IOCTL+0x8d sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806834a2e8,c0384600,ffff80002cf954f0,ffff80002175f268) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:525 sys_ioctl(ffff80002175f268,ffff80002cf95608,ffff80002cf95650) at sys_ioctl+0x49e syscall(ffff80002cf956d0) at syscall+0x446 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xac283d81f60, count: -9