panic: free: non-malloced addr 0xffff800020abf8c8 type in_multi Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *466856 44322 0 0 0x4000000 1K syz-executor.1 50747 68468 0 0x14000 0x200 0 systqmp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 free(ffff800020abf8c8,36,18) at free+0x50c in6_purgeaddr(ffff800000ad5100) at in6_purgeaddr+0x1b7 sys/netinet6/in6.c:913 in6_ifdetach(ffff800000aca000) at in6_ifdetach+0x74 sys/netinet6/in6_ifattach.c:422 ifioctl(fffffd8079d137d8,801169ac,ffff800022bb54c0,ffff800020abf650) at ifioctl+0x12a8 sys/net/if.c:1929 sys_ioctl(ffff800020abf650,ffff800022bb55d8,ffff800022bb5620) at sys_ioctl+0x5b9 syscall(ffff800022bb56a0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800022bb56a0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,0,ffffffffffffff36,0,3,ea6a4783010) at Xsyscall+0x128 end of kernel end trace frame: 0xea91943ea70, 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic free: non-malloced addr 0xffff800020abf8c8 type in_multi ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 free(ffff800020abf8c8,36,18) at free+0x50c in6_purgeaddr(ffff800000ad5100) at in6_purgeaddr+0x1b7 sys/netinet6/in6.c:913 in6_ifdetach(ffff800000aca000) at in6_ifdetach+0x74 sys/netinet6/in6_ifattach.c:422 ifioctl(fffffd8079d137d8,801169ac,ffff800022bb54c0,ffff800020abf650) at ifioctl+0x12a8 sys/net/if.c:1929 sys_ioctl(ffff800020abf650,ffff800022bb55d8,ffff800022bb5620) at sys_ioctl+0x5b9 syscall(ffff800022bb56a0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800022bb56a0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,0,ffffffffffffff36,0,3,ea6a4783010) at Xsyscall+0x128 end of kernel end trace frame: 0xea91943ea70, count: -9 ddb{1}> show registers rdi 0xffffffff811e1b57 db_enter+0x17 rsi 0xdbb5 __ALIGN_SIZE+0xcbb5 rbp 0xffff800022bb51b0 rbx 0xffff800022bb5260 rdx 0xdbb6 __ALIGN_SIZE+0xcbb6 rcx 0xffff800021b88000 rax 0xffff800021b88000 r8 0xffffffff81f17eff kprintf+0x16f r9 0x1 r10 0x25 r11 0x8d3ee7d005ee0849 r12 0x3000000008 r13 0xffff800022bb51c0 r14 0x100 r15 0x1 rip 0xffffffff811e1b58 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800022bb51a0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=466856 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=81, nice=20 forw=0xffffffffffffffff, list=0xffff800020abe508,0xffffffff8262b3e0 process=0xffff800020addc00 user=0xffff800022bb0000, vmspace=0xfffffd807f00b450 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 44322 273731 53235 0 2 0 syz-executor.1 *44322 466856 53235 0 7 0x4000000 syz-executor.1 75538 122786 49183 0 2 0 syz-executor.0 75538 141444 49183 0 2 0x4000000 syz-executor.0 49183 195784 14125 0 3 0x82 nanosleep syz-executor.0 53235 19434 14125 0 3 0x82 nanosleep syz-executor.1 74871 461193 1 0 3 0x100083 ttyin getty 44212 521646 0 0 3 0x14200 bored sosplice 14125 424781 23327 0 3 0x82 thrsleep syz-fuzzer 14125 405210 23327 0 3 0x4000082 nanosleep syz-fuzzer 14125 260818 23327 0 3 0x4000082 kqread syz-fuzzer 14125 387736 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 349656 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 522442 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 379328 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 395862 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 348052 23327 0 3 0x4000082 thrsleep syz-fuzzer 14125 251974 23327 0 3 0x4000082 thrsleep syz-fuzzer 23327 241651 93338 0 3 0x10008a pause ksh 93338 217448 82927 0 3 0x92 select sshd 82927 272779 1 0 3 0x80 select sshd 34575 72771 644 74 3 0x100092 bpf pflogd 644 150032 1 0 3 0x80 netio pflogd 16473 297726 50368 73 3 0x100090 kqread syslogd 50368 257971 1 0 3 0x100082 netio syslogd 6110 450545 1 77 3 0x100090 poll dhclient 51319 277033 1 0 3 0x80 poll dhclient 54234 503192 0 0 2 0x14200 zerothread 6818 196344 0 0 3 0x14200 aiodoned aiodoned 21859 120407 0 0 3 0x14200 syncer update 16747 169140 0 0 3 0x14200 cleaner cleaner 33145 428428 0 0 3 0x14200 reaper reaper 3781 502743 0 0 3 0x14200 pgdaemon pagedaemon 82828 465157 0 0 3 0x14200 bored crynlk 67481 132482 0 0 3 0x14200 bored crypto 43834 288749 0 0 3 0x40014200 acpi0 acpi0 89422 266263 0 0 3 0x40014200 idle1 36945 203022 0 0 3 0x14200 bored softnet 68468 50747 0 0 7 0x14200 systqmp 76849 265375 0 0 3 0x14200 bored systq 25238 215427 0 0 3 0x40014200 bored softclock 42813 84552 0 0 3 0x40014200 idle0 62077 469102 0 0 3 0x14200 bored smr 1 349606 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 44322 (syz-executor.1) thread 0xffff800020abf650 (466856) exclusive rwlock netlock r = 0 (0xffffffff824f1a78) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 ifioctl+0xc62 sys/net/if.c:1917 #3 sys_ioctl+0x5b9 #4 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #4 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #5 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82628c50) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 #2 mi_switch+0x392 sys/kern/sched_bsd.c:441 #3 sleep_finish+0x113 sys/kern/kern_synch.c:373 #4 rw_enter+0x352 sys/kern/kern_rwlock.c:282 #5 ifioctl+0xc62 sys/net/if.c:1917 #6 sys_ioctl+0x5b9 #7 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #7 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #8 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9562 7202K 8361K 78643K 13572 0 0 pcb 13 8K 8K 78643K 190 0 0 rtable 87 8K 8K 78643K 871 0 0 ifaddr 71 14K 16K 78643K 257 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1512 0 0 iov 0 0K 32K 78643K 203 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 77K 78643K 2199 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 23 0 0 VM map 9 4K 4K 78643K 14 0 0 sem 12 1K 1K 78643K 16 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 25K 78643K 1006 0 0 sigio 0 0K 0K 78643K 27 0 0 proc 60 63K 95K 78643K 686 0 0 subproc 32 2K 2K 78643K 85 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 79 0 0 in_multi 13 0K 2K 78643K 125 0 0 ether_multi 1 0K 0K 78643K 11 0 0 mrt 0 0K 0K 78643K 10 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 66 291K 291K 78643K 66 0 0 exec 0 0K 1K 78643K 365 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 129 103K 104K 78643K 4596 0 0 UVM aobj 86 5K 5K 78643K 90 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 175 0 0 NDP 17 0K 0K 78643K 78 0 0 temp 208 3564K 4204K 78643K 35522 0 0 kqueue 0 0K 0K 78643K 13 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 39 0 36 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 81 0 79 1 0 1 1 0 8 0 rtentry 112 162 0 133 2 0 2 2 0 8 0 unpcb 120 552 0 542 2 1 1 2 0 8 0 syncache 264 9 0 9 4 4 0 1 0 8 0 tcpqe 32 241 0 241 3 3 0 2 0 8 0 tcpcb 544 356 0 352 1 0 1 1 0 8 0 inpcb 280 2348 0 2338 5 3 2 3 0 8 1 rttmr 72 4 0 4 3 3 0 1 0 8 0 ip6q 72 1 0 0 1 0 1 1 0 8 0 nd6 48 17 0 16 2 1 1 1 0 8 0 pkpcb 40 6 0 6 2 2 0 1 0 8 0 swfcl 56 8 0 0 1 0 1 1 0 8 0 ppxss 1128 31 0 31 4 3 1 1 0 8 1 pffrag 232 7 0 7 4 3 1 1 0 482 1 pffrnode 88 7 0 7 4 3 1 1 0 8 1 pffrent 40 272 0 272 4 3 1 1 0 8 1 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 97 0 49 1 0 1 1 0 8 0 pfstkey 112 97 0 49 2 0 2 2 0 8 0 pfstate 328 97 0 49 5 0 5 5 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 11 0 8 5 1 4 4 0 8 1 art_heap4 256 794 0 580 21 6 15 17 0 8 0 art_table 32 805 0 588 3 0 3 3 0 8 0 art_node 16 160 0 129 1 0 1 1 0 8 0 sysvmsgpl 40 29 0 19 1 0 1 1 0 8 0 semupl 112 4 0 4 1 1 0 1 0 8 0 semapl 112 14 0 4 1 0 1 1 0 8 0 shmpl 112 88 0 4 3 0 3 3 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2957 0 1559 46 0 46 46 0 8 0 ffsino 272 2957 0 1559 95 0 95 95 0 8 0 nchpl 144 4810 0 3198 61 0 61 61 0 8 0 uvmvnodes 72 3725 0 0 68 0 68 68 0 8 0 vnodes 208 3725 0 0 197 0 197 197 0 8 0 namei 1024 15036 0 15036 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 7 0 0 1 0 1 1 0 8 0 vmpool 552 12 0 5 1 0 1 1 0 8 0 scxspl 192 13598 0 13598 15 14 1 6 0 8 1 plimitpl 152 92 0 84 1 0 1 1 0 8 0 sigapl 432 1200 0 1184 3 1 2 3 0 8 0 futexpl 56 21669 0 21669 1 0 1 1 0 8 1 knotepl 112 229 0 210 1 0 1 1 0 8 0 kqueuepl 104 483 0 481 1 0 1 1 0 8 0 pipepl 112 648 0 629 2 1 1 1 0 8 0 fdescpl 488 1201 0 1184 3 0 3 3 0 8 0 filepl 152 9871 0 9768 10 4 6 7 0 8 2 lockfpl 104 353 0 352 1 0 1 1 0 8 0 lockfspl 48 128 0 127 1 0 1 1 0 8 0 sessionpl 112 24 0 13 1 0 1 1 0 8 0 pgrppl 48 26 0 15 1 0 1 1 0 8 0 ucredpl 96 1005 0 996 1 0 1 1 0 8 0 zombiepl 144 1184 0 1184 2 1 1 1 0 8 1 processpl 896 1217 0 1184 4 0 4 4 0 8 0 procpl 632 3616 0 3572 6 1 5 5 0 8 1 srpgc 64 6 0 6 3 3 0 1 0 8 0 sosppl 128 14 0 14 5 4 1 1 0 8 1 sockpl 384 3011 0 2989 14 10 4 9 0 8 1 mcl64k 65536 263 0 0 33 6 27 33 0 8 1 mcl16k 16384 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 13 0 0 2 0 2 2 0 8 0 mcl9k 9216 7 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 12 0 0 2 0 2 2 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 250 0 0 31 0 31 31 0 8 0 mtagpl 80 27 0 0 1 0 1 1 0 8 0 mbufpl 256 376 0 0 22 0 22 22 0 8 0 bufpl 256 8370 0 1326 441 0 441 441 0 8 0 anonpl 16 155687 0 136475 113 22 91 91 0 124 12 amapchunkpl 152 8332 0 8174 20 8 12 14 0 158 5 amappl16 192 7051 0 5999 93 32 61 63 0 8 8 amappl15 184 9 0 9 1 1 0 1 0 8 0 amappl14 176 46 0 44 2 1 1 1 0 8 0 amappl13 168 330 0 328 2 1 1 1 0 8 0 amappl12 160 211 0 209 2 1 1 1 0 8 0 amappl11 152 306 0 291 1 0 1 1 0 8 0 amappl10 144 165 0 160 1 0 1 1 0 8 0 amappl9 136 668 0 660 1 0 1 1 0 8 0 amappl8 128 218 0 188 3 1 2 2 0 8 0 amappl7 120 204 0 198 1 0 1 1 0 8 0 amappl6 112 317 0 304 1 0 1 1 0 8 0 amappl5 104 369 0 353 1 0 1 1 0 8 0 amappl4 96 1522 0 1485 2 1 1 2 0 8 0 amappl3 88 357 0 351 1 0 1 1 0 8 0 amappl2 80 8676 0 8590 4 2 2 3 0 8 0 amappl1 72 36316 0 35850 25 15 10 20 0 8 0 amappl 80 3951 0 3897 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 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 17 0 17 1 1 0 1 0 8 0 aobjpl 64 89 0 4 2 0 2 2 0 8 0 uaddrrnd 24 1213 0 1184 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1213 0 1184 1 0 1 1 0 8 0 vmmpekpl 168 13558 0 13525 2 0 2 2 0 8 0 vmmpepl 168 158328 0 155989 175 65 110 135 0 357 7 vmsppl 368 1200 0 1184 2 0 2 2 0 8 0 pdppl 4096 2433 0 2385 8 1 7 7 0 8 1 pvpl 32 426041 0 404066 244 34 210 210 0 265 32 pmappl 232 1212 0 1189 3 1 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 671 0 17 19 0 19 19 0 8 0