panic: Data modified on freelist: word 4 of object 0xffff800001427a00 size 0x194 previous type free (0x6563 != 0xdeaf4152) Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *384261 7622 0 0 0x4000000 0 syz-executor.7 db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83323de4) at panic+0x1cf sys/kern/subr_prf.c:198 malloc(194,2,a) at malloc+0xcf8 sys/kern/kern_malloc.c:353 disk_attach(ffff800000b3d000,ffff800000b3d048) at disk_attach+0xc0 sys/kern/subr_disk.c:1070 vndioctl(2902,c0384600,ffff80002a9592c0,1,ffff80002a80efb8) at vndioctl+0x1122 sys/dev/vnd.c:540 VOP_IOCTL(fffffd8079fa7138,c0384600,ffff80002a9592c0,1,fffffd8007bfb618,ffff80002a80efb8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806901f9d8,c0384600,ffff80002a9592c0,ffff80002a80efb8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531 sys_ioctl(ffff80002a80efb8,ffff80002a959490,ffff80002a9593e0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1 syscall(ffff80002a959490) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a959490) at syscall+0x962 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5a82defa470, 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: Data modified on freelist: word 4 of object 0xffff800001427a00 size 0x194 previous type free (0x6563 != 0xdeaf4152) ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83323de4) at panic+0x1cf sys/kern/subr_prf.c:198 malloc(194,2,a) at malloc+0xcf8 sys/kern/kern_malloc.c:353 disk_attach(ffff800000b3d000,ffff800000b3d048) at disk_attach+0xc0 sys/kern/subr_disk.c:1070 vndioctl(2902,c0384600,ffff80002a9592c0,1,ffff80002a80efb8) at vndioctl+0x1122 sys/dev/vnd.c:540 VOP_IOCTL(fffffd8079fa7138,c0384600,ffff80002a9592c0,1,fffffd8007bfb618,ffff80002a80efb8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806901f9d8,c0384600,ffff80002a9592c0,ffff80002a80efb8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531 sys_ioctl(ffff80002a80efb8,ffff80002a959490,ffff80002a9593e0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1 syscall(ffff80002a959490) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a959490) at syscall+0x962 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5a82defa470, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002a9588d0 rbx 0xffff800001427a00 rdx 0x3fd rcx 0 rax 0x7c r8 0x101010101010101 r9 0x8080808080808080 r10 0x4d18238d65b52451 r11 0x2d8a423d7cceeffb r12 0 r13 0xffffffff8396dc40 kmemstats+0x80 r14 0 r15 0x1 rip 0xffffffff82f22e45 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a9588c0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (syz-executor.7) tid=384261 pid=7622 tcnt=2 stat=onproc flags process=0 proc=4000000 runpri=32, usrpri=60, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a80fa18,0xffff80002a80f790 process=0xffff80002a797608 user=0xffff80002a954000, vmspace=0xfffffd8009427000 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 93576 437362 8202 0 2 0 syz-executor.1 93576 470586 8202 0 3 0x4000080 fsleep syz-executor.1 90322 182270 45966 0 2 0 syz-executor.6 90322 371493 45966 0 2 0x4000000 syz-executor.6 43352 75956 98043 0 2 0 syz-executor.4 43352 166632 98043 0 3 0x4000080 fsleep syz-executor.4 4531 99106 74077 0 2 0 syz-executor.0 7622 501674 85522 0 2 0 syz-executor.7 * 7622 384261 85522 0 7 0x4000000 syz-executor.7 264 112492 22220 0 2 0 syz-executor.5 264 457125 22220 0 3 0x4000080 fsleep syz-executor.5 97946 80348 94253 0 2 0 syz-executor.3 97946 267355 94253 0 3 0x4000080 fsleep syz-executor.3 85522 260135 58367 0 3 0x82 nanoslp syz-executor.7 94253 264924 58367 0 3 0x82 nanoslp syz-executor.3 45966 48780 58367 0 3 0x82 nanoslp syz-executor.6 22220 446055 58367 0 3 0x82 nanoslp syz-executor.5 98043 148808 58367 0 3 0x82 nanoslp syz-executor.4 94236 70867 58367 0 2 0x2 syz-executor.2 8202 137952 58367 0 3 0x82 nanoslp syz-executor.1 74077 44250 58367 0 3 0x82 nanoslp syz-executor.0 58367 476592 84848 0 3 0x82 wait syz-execprog 58367 458576 84848 0 3 0x4000082 thrsleep syz-execprog 58367 157207 84848 0 3 0x4000082 wait syz-execprog 58367 340868 84848 0 3 0x4000082 thrsleep syz-execprog 58367 278476 84848 0 3 0x4000082 wait syz-execprog 58367 78205 84848 0 3 0x4000082 wait syz-execprog 58367 156257 84848 0 3 0x4000082 thrsleep syz-execprog 58367 505317 84848 0 3 0x4000082 wait syz-execprog 58367 222578 84848 0 3 0x4000082 thrsleep syz-execprog 58367 19819 84848 0 3 0x4000082 wait syz-execprog 58367 49574 84848 0 3 0x4000082 wait syz-execprog 58367 93658 84848 0 3 0x4000082 wait syz-execprog 58367 332700 84848 0 3 0x4000082 kqread syz-execprog 84848 362772 33371 0 3 0x10008a sigsusp ksh 33371 142775 81568 0 3 0x98 kqread sshd-session 81568 427619 5758 0 3 0x92 kqread sshd-session 70260 319611 1 0 3 0x100083 ttyin getty 5758 383111 1 0 3 0x88 kqread sshd 46780 397461 68237 73 3 0x1100090 kqread syslogd 68237 199520 1 0 3 0x100082 sbwait syslogd 72718 73508 1 0 3 0x100080 kqread resolvd 33397 37053 51142 77 3 0x100092 kqread dhcpleased 49912 157309 51142 77 3 0x100092 kqread dhcpleased 51142 517842 1 0 3 0x80 kqread dhcpleased 83367 160308 0 0 3 0x14200 bored smr 67356 492614 0 0 2 0x14200 zerothread 52664 78239 0 0 3 0x14200 aiodoned aiodoned 97569 63298 0 0 3 0x14200 syncer update 83344 391249 0 0 3 0x14200 cleaner cleaner 7513 162608 0 0 3 0x14200 reaper reaper 44679 164767 0 0 3 0x14200 pgdaemon pagedaemon 12653 162802 0 0 3 0x14200 bored viomb 95694 455245 0 0 3 0x40014200 acpi0 acpi0 30349 84085 0 0 3 0x14200 bored softnet0 27828 277759 0 0 3 0x14200 bored systqmp 96275 367048 0 0 3 0x14200 bored systq 92728 147183 0 0 3 0x40014200 tmoslp softclock 20625 106353 0 0 3 0x40014200 idle0 1 180746 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 10162 11040K 11053K 166960K 11316 0 pcb 17 12K 12K 166960K 17 0 rtable 237 6K 6K 166960K 383 0 pf 30 12K 12K 166960K 33 0 ifaddr 42 7K 7K 166960K 48 0 ifgroup 50 2K 2K 166960K 55 0 sysctl 1 1K 9K 166960K 5 0 counters 32 17K 17K 166960K 33 0 ioctlops 0 0K 2K 166960K 30 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1263 79K 80K 166960K 1284 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 1K 166960K 2 0 VM map 2 1K 1K 166960K 2 0 sem 2 0K 0K 166960K 2 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 73K 166960K 259 0 proc 57 58K 75K 166960K 499 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 in_multi 99 7K 7K 166960K 110 0 ether_multi 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 25 122K 122K 166960K 25 0 exec 0 0K 1K 166960K 427 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 256 145K 198K 166960K 5243 0 UVM aobj 3 2K 2K 166960K 3 0 pinsyscall 39 78K 104K 166960K 1649 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 NDP 11 0K 2K 166960K 30 0 temp 1 8636K 8700K 166960K 5118 0 kqueue 13 20K 20K 166960K 46 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 38 0 35 1 0 1 1 0 8 0 rtentry 136 122 0 12 4 0 4 4 0 8 0 unpcb 144 67 0 52 1 0 1 1 0 8 0 syncache 336 9 0 9 1 0 1 1 0 8 1 tcpcb 736 12 0 9 1 0 1 1 0 8 0 arp 96 20 0 2 1 0 1 1 0 8 0 inpcb 328 66 0 60 1 0 1 1 0 8 0 nd6 112 27 0 3 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 500 0 48 29 0 29 29 0 8 0 art_table 40 501 0 48 5 0 5 5 0 8 0 art_node 32 122 0 22 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1831 0 303 96 0 96 96 0 8 0 ffsino 256 1831 0 303 96 0 96 96 0 8 0 nchpl 144 2315 0 538 67 0 67 67 0 8 0 vnodes 216 1841 0 0 103 0 103 103 0 8 0 namei 1024 8106 0 8106 3 0 3 3 0 8 3 kstatmem 264 24 0 2 2 0 2 2 0 8 0 scxspl 216 17257 0 17256 8 0 8 8 1 8 7 plimitpl 152 58 0 42 1 0 1 1 0 8 0 sigapl 424 605 0 563 6 0 6 6 0 8 1 knotepl 120 7192 0 7113 3 0 3 3 0 8 0 kqueuepl 184 42 0 33 1 0 1 1 0 8 0 pipepl 304 188 0 160 3 0 3 3 0 8 0 fdescpl 448 592 0 563 4 0 4 4 0 8 0 filepl 120 2412 0 2272 5 0 5 5 0 8 0 lockfpl 104 6 0 4 1 0 1 1 0 8 0 lockfspl 48 4 0 2 1 0 1 1 0 8 0 sessionpl 144 34 0 18 1 0 1 1 0 8 0 pgrppl 48 34 0 18 1 0 1 1 0 8 0 ucredpl 104 195 0 183 1 0 1 1 0 8 0 zombiepl 144 563 0 563 1 0 1 1 0 8 1 processpl 1152 605 0 563 4 0 4 4 0 8 1 procpl 664 743 0 683 6 0 6 6 0 8 0 sockpl 552 171 0 147 2 0 2 2 0 8 0 mcl8k 8192 4 0 4 1 0 1 1 0 8 1 mcl4k 4096 8847 0 8790 19 4 15 19 0 8 7 mcl2k 2048 275 0 275 1 0 1 1 0 8 1 mtagpl 96 4 0 4 1 0 1 1 0 8 1 mbufpl 256 12419 0 12261 10 0 10 10 0 8 0 bufpl 280 11777 0 5488 450 0 450 450 0 8 0 anonpl 24 236037 0 231180 59 0 59 59 0 187 26 amapchunkpl 152 16143 0 15571 29 0 29 29 0 158 6 amappl16 200 5871 0 5736 10 0 10 10 0 8 2 amappl15 192 8 0 8 1 0 1 1 0 8 1 amappl14 184 40 0 38 1 0 1 1 0 8 0 amappl13 176 468 0 465 1 0 1 1 0 8 0 amappl12 168 1059 0 1020 3 0 3 3 0 8 1 amappl11 160 51 0 51 1 0 1 1 0 8 1 amappl10 152 104 0 86 1 0 1 1 0 8 0 amappl9 144 947 0 947 1 0 1 1 0 8 1 amappl8 136 210 0 182 1 0 1 1 0 8 0 amappl7 128 174 0 167 2 0 2 2 0 8 1 amappl6 120 412 0 398 2 0 2 2 0 8 1 amappl5 112 170 0 162 1 0 1 1 0 8 0 amappl4 104 639 0 608 2 0 2 2 0 8 0 amappl3 96 2161 0 2065 3 0 3 3 0 8 0 amappl2 88 1029 0 973 5 0 5 5 0 8 2 amappl1 80 17901 0 17332 28 7 21 23 0 8 8 amappl 88 4056 0 3894 4 0 4 4 0 92 0 uvmvnodes 80 1841 0 0 38 0 38 38 0 8 0 dma4096 4096 1 0 1 1 0 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 0 1 1 0 8 1 dma128 128 253 0 253 1 0 1 1 0 8 1 dma64 64 6 0 6 1 0 1 1 0 8 1 dma32 32 7 0 7 1 0 1 1 0 8 1 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 592 0 563 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 592 0 563 1 0 1 1 0 8 0 vmmpekpl 168 12368 0 12331 2 0 2 2 0 8 0 vmmpepl 168 71018 0 69143 122 0 122 122 0 357 40 vmsppl 368 591 0 563 3 0 3 3 0 8 0 rwobjpl 40 29656 0 26831 34 0 34 34 0 8 2 pdppl 4096 1191 0 1126 113 46 67 71 0 8 2 pvpl 32 616793 0 606383 512 164 348 444 0 265 262 pmappl 216 591 0 563 2 0 2 2 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 384 0 50 10 0 10 10 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83323de4) at panic+0x1cf sys/kern/subr_prf.c:198 malloc(194,2,a) at malloc+0xcf8 sys/kern/kern_malloc.c:353 disk_attach(ffff800000b3d000,ffff800000b3d048) at disk_attach+0xc0 sys/kern/subr_disk.c:1070 vndioctl(2902,c0384600,ffff80002a9592c0,1,ffff80002a80efb8) at vndioctl+0x1122 sys/dev/vnd.c:540 VOP_IOCTL(fffffd8079fa7138,c0384600,ffff80002a9592c0,1,fffffd8007bfb618,ffff80002a80efb8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806901f9d8,c0384600,ffff80002a9592c0,ffff80002a80efb8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531 sys_ioctl(ffff80002a80efb8,ffff80002a959490,ffff80002a9593e0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1 syscall(ffff80002a959490) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a959490) at syscall+0x962 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5a82defa470, count: -10 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83323de4) at panic+0x1cf sys/kern/subr_prf.c:198 malloc(194,2,a) at malloc+0xcf8 sys/kern/kern_malloc.c:353 disk_attach(ffff800000b3d000,ffff800000b3d048) at disk_attach+0xc0 sys/kern/subr_disk.c:1070 vndioctl(2902,c0384600,ffff80002a9592c0,1,ffff80002a80efb8) at vndioctl+0x1122 sys/dev/vnd.c:540 VOP_IOCTL(fffffd8079fa7138,c0384600,ffff80002a9592c0,1,fffffd8007bfb618,ffff80002a80efb8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806901f9d8,c0384600,ffff80002a9592c0,ffff80002a80efb8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531 sys_ioctl(ffff80002a80efb8,ffff80002a959490,ffff80002a9593e0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1 syscall(ffff80002a959490) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a959490) at syscall+0x962 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5a82defa470, count: -10