panic(ffffffff821f32ce) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82661280) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82661280) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82661280,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd80695f8000,0,3b9aca00,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd80695f8000,0,3b9aca00,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 rtm_sendup(fffffd806a90e650,fffffd80695f8000,1) at rtm_sendup+0x5f sys/net/rtsock.c:588 route_input(fffffd80695f8000,0,18) at route_input+0x1cc sys/net/rtsock.c:560 rtm_send(fffffd806f6a0d90,2,0,0) at rtm_send+0x18d sys/net/rtsock.c:1661 rt_ifa_del(ffff8000006b1e00,200004,ffff8000006b1e40,0) at rt_ifa_del+0x3bb sys/net/route.c:1189 rt_ifa_dellocal(ffff8000006b1e00) at rt_ifa_dellocal+0x149 sys/net/route.c:1289 in6_purgeaddr(ffff8000006b1e00) at in6_purgeaddr+0x114 sys/netinet6/in6.c:922 in6_ioctl_change_ifaddr(81206919,ffff800000a2ee00,ffff800000679800) at in6_ioctl_change_ifaddr+0x2c0 ifioctl(fffffd806a90eb00,81206919,ffff800000a2ee00,ffff800020ac64f8) at ifioctl+0xe70 sys/net/if.c:2289 soo_ioctl(fffffd8067bba578,81206919,ffff800000a2ee00,ffff800020ac64f8) at soo_ioctl+0x27c sys/kern/sys_socket.c:138 end trace frame: 0xffff8000225cdd50, count: 0 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd8070d30b00+16 0x0!=0x99d028a2aa8ecd6 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821f32ce) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82661280) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82661280) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82661280,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd80695f8000,0,3b9aca00,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd80695f8000,0,3b9aca00,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 rtm_sendup(fffffd806a90e650,fffffd80695f8000,1) at rtm_sendup+0x5f sys/net/rtsock.c:588 route_input(fffffd80695f8000,0,18) at route_input+0x1cc sys/net/rtsock.c:560 rtm_send(fffffd806f6a0d90,2,0,0) at rtm_send+0x18d sys/net/rtsock.c:1661 rt_ifa_del(ffff8000006b1e00,200004,ffff8000006b1e40,0) at rt_ifa_del+0x3bb sys/net/route.c:1189 rt_ifa_dellocal(ffff8000006b1e00) at rt_ifa_dellocal+0x149 sys/net/route.c:1289 in6_purgeaddr(ffff8000006b1e00) at in6_purgeaddr+0x114 sys/netinet6/in6.c:922 in6_ioctl_change_ifaddr(81206919,ffff800000a2ee00,ffff800000679800) at in6_ioctl_change_ifaddr+0x2c0 ifioctl(fffffd806a90eb00,81206919,ffff800000a2ee00,ffff800020ac64f8) at ifioctl+0xe70 sys/net/if.c:2289 soo_ioctl(fffffd8067bba578,81206919,ffff800000a2ee00,ffff800020ac64f8) at soo_ioctl+0x27c sys/kern/sys_socket.c:138 sys_ioctl(ffff800020ac64f8,ffff8000225cdd68,ffff8000225cddb0) at sys_ioctl+0x4a5 syscall(ffff8000225cde30) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000225cde30) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x51bd9f0fcb0, count: -17 ddb{0}> show registers rdi 0xffffffff81266fa7 db_enter+0x17 rsi 0x6154 __ALIGN_SIZE+0x5154 rbp 0xffff8000225cd370 rbx 0xffff8000225cd420 rdx 0x6155 __ALIGN_SIZE+0x5155 rcx 0xffff800021b8e000 rax 0xffff800021b8e000 r8 0xffffffff815fbfbf kprintf+0x16f r9 0x1 r10 0x25 r11 0xa20b84675b10f95d r12 0x3000000008 r13 0xffff8000225cd380 r14 0x100 r15 0x1 rip 0xffffffff81266fa8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000225cd360 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.1) pid=422007 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=60, nice=20 forw=0xffffffffffffffff, list=0xffff800020ac7ae8,0xffffffff8265b2d8 process=0xffff800020a93358 user=0xffff8000225c8000, vmspace=0xfffffd807f000170 estcpu=10, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 9354 77033 66725 0 2 0 syz-executor.1 9354 357461 66725 0 2 0x4000000 syz-executor.1 * 9354 422007 66725 0 7 0x4000000 syz-executor.1 1868 357537 92103 0 2 0 syz-executor.0 1868 159501 92103 0 3 0x4000080 poll syz-executor.0 1868 214995 92103 0 7 0x4000000 syz-executor.0 66725 117410 82985 0 3 0x82 nanosleep syz-executor.1 92103 37294 82985 0 3 0x82 nanosleep syz-executor.0 82985 58963 98831 0 3 0x82 thrsleep syz-fuzzer 82985 17074 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 234201 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 31478 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 25269 98831 0 3 0x4000082 kqread syz-fuzzer 82985 55400 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 42626 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 41413 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 356281 98831 0 3 0x4000082 thrsleep syz-fuzzer 82985 513100 98831 0 3 0x4000082 thrsleep syz-fuzzer 98831 314005 62638 0 3 0x10008a pause ksh 62638 66106 68564 0 3 0x92 select sshd 36376 219683 1 0 3 0x100083 ttyin getty 68564 473661 1 0 3 0x80 select sshd 73946 343075 34591 74 3 0x100092 bpf pflogd 34591 25316 1 0 3 0x80 netio pflogd 29801 18224 99903 73 3 0x100090 kqread syslogd 99903 458887 1 0 3 0x100082 netio syslogd 39217 435655 1 77 3 0x100090 poll dhclient 73906 337759 1 0 3 0x80 poll dhclient 52737 62678 0 0 3 0x14200 bored smr 96054 483873 0 0 2 0x14200 zerothread 77312 92219 0 0 3 0x14200 aiodoned aiodoned 87924 399746 0 0 3 0x14200 syncer update 74485 137031 0 0 3 0x14200 cleaner cleaner 94322 380655 0 0 3 0x14200 reaper reaper 79925 519865 0 0 3 0x14200 pgdaemon pagedaemon 77633 352955 0 0 3 0x14200 bored crynlk 74842 425347 0 0 3 0x14200 bored crypto 78650 58957 0 0 3 0x40014200 acpi0 acpi0 41166 450128 0 0 3 0x40014200 idle1 13508 452315 0 0 3 0x14200 bored softnet 72634 160428 0 0 3 0x14200 bored systqmp 31699 284670 0 0 3 0x14200 bored systq 34051 389025 0 0 3 0x40014200 bored softclock 44072 378648 0 0 3 0x40014200 idle0 1 522220 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 1: exclusive mutex /syzkaller/managers/multicore/kernel/sys/kern/kern_task.c:86 r = 0 (0xffffffff82508820) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 taskq_next_work+0x38 sys/kern/kern_task.c:313 #4 taskq_thread+0xe5 sys/kern/kern_task.c:366 #5 proc_trampoline+0x1c Process 9354 (syz-executor.1) thread 0xffff800020ac64f8 (422007) exclusive rwlock netlock r = 0 (0xffffffff824cef48) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 in6_ioctl_change_ifaddr+0xab #2 ifioctl+0xe70 sys/net/if.c:2289 #3 soo_ioctl+0x27c sys/kern/sys_socket.c:138 #4 sys_ioctl+0x4a5 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8264e180) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 soo_ioctl+0x26a sys/kern/sys_socket.c:138 #2 sys_ioctl+0x4a5 #3 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #3 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #4 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9491 6468K 6660K 78643K 10640 0 pcb 13 8K 8K 78643K 21 0 rtable 108 3K 4K 78643K 258 0 ifaddr 53 11K 12K 78643K 64 0 counters 43 33K 33K 78643K 45 0 ioctlops 1 0K 4K 78643K 1473 0 iov 0 0K 4K 78643K 39 0 mount 1 1K 1K 78643K 1 0 vnodes 1219 77K 77K 78643K 1264 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 2 0K 0K 78643K 2 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 6 17K 25K 78643K 88 0 sigio 0 0K 0K 78643K 1 0 proc 61 63K 95K 78643K 490 0 subproc 32 2K 2K 78643K 51 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 3 0 in_multi 33 2K 2K 78643K 46 0 ether_multi 1 0K 0K 78643K 2 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 31 148K 148K 78643K 31 0 exec 0 0K 1K 78643K 220 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 98 21K 21K 78643K 1192 0 UVM aobj 2 2K 2K 78643K 2 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 7 0 NDP 8 0K 0K 78643K 15 0 temp 81 3037K 3103K 78643K 3239 0 kqueue 3 4K 12K 78643K 14 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 8 0 2 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 26 0 23 1 0 1 1 0 8 0 rtentry 112 57 0 13 2 0 2 2 0 8 0 unpcb 120 56 0 46 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 44 0 44 1 1 0 1 0 8 0 tcpcb 544 30 0 24 1 0 1 1 0 8 0 inpcb 280 86 0 76 1 0 1 1 0 8 0 nd6 48 10 0 4 1 0 1 1 0 8 0 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 17 0 0 1 0 1 1 0 8 0 pfstkey 112 17 0 0 1 0 1 1 0 8 0 pfstate 328 17 0 0 2 0 2 2 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 248 0 67 13 0 13 13 0 8 1 art_table 32 249 0 67 2 0 2 2 0 8 0 art_node 16 56 0 17 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1492 0 86 46 0 46 46 0 8 0 ffsino 272 1492 0 86 95 1 94 95 0 8 0 nchpl 144 1803 0 198 61 0 61 61 0 8 0 uvmvnodes 72 1570 0 0 29 0 29 29 0 8 0 vnodes 208 1570 0 0 83 0 83 83 0 8 0 namei 1024 4933 0 4933 1 0 1 1 0 8 1 percpumem 16 33 0 1 1 0 1 1 0 8 0 scxspl 192 6116 0 6116 8 1 7 7 0 8 7 plimitpl 152 16 0 8 1 0 1 1 0 8 0 sigapl 424 300 0 268 4 0 4 4 0 8 0 futexpl 56 722 0 722 1 0 1 1 0 8 1 knotepl 112 75 0 56 1 0 1 1 0 8 0 kqueuepl 144 24 0 22 1 0 1 1 0 8 0 pipelkpl 48 88 0 75 1 0 1 1 0 8 0 pipepl 120 176 0 151 1 0 1 1 0 8 0 fdescpl 496 285 0 268 3 0 3 3 0 8 0 filepl 152 1488 0 1377 5 0 5 5 0 8 0 lockfpl 104 13 0 12 1 0 1 1 0 8 0 lockfspl 48 5 0 4 1 0 1 1 0 8 0 sessionpl 112 19 0 8 1 0 1 1 0 8 0 pgrppl 48 19 0 8 1 0 1 1 0 8 0 ucredpl 96 78 0 69 1 0 1 1 0 8 0 zombiepl 144 268 0 268 1 0 1 1 0 8 1 processpl 984 300 0 268 5 0 5 5 0 8 0 procpl 624 405 0 360 4 0 4 4 0 8 0 sockpl 400 168 0 145 3 0 3 3 0 8 0 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 168 0 0 20 0 20 20 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 178 0 0 11 0 11 11 0 8 0 bufpl 280 4823 0 176 332 0 332 332 0 8 0 anonpl 16 50127 0 36931 69 1 68 68 0 124 14 amapchunkpl 152 1536 0 1400 8 1 7 8 0 158 1 amappl16 192 1501 0 799 49 3 46 46 0 8 10 amappl15 184 17 0 15 1 0 1 1 0 8 0 amappl14 176 2 0 2 2 2 0 1 0 8 0 amappl13 168 32 0 31 1 0 1 1 0 8 0 amappl12 160 5 0 4 1 0 1 1 0 8 0 amappl11 152 99 0 79 1 0 1 1 0 8 0 amappl10 144 18 0 13 1 0 1 1 0 8 0 amappl9 136 399 0 394 1 0 1 1 0 8 0 amappl8 128 346 0 331 1 0 1 1 0 8 0 amappl7 120 128 0 114 1 0 1 1 0 8 0 amappl6 112 45 0 40 1 0 1 1 0 8 0 amappl5 104 183 0 167 1 0 1 1 0 8 0 amappl4 96 532 0 500 2 1 1 2 0 8 0 amappl3 88 104 0 98 1 0 1 1 0 8 0 amappl2 80 1277 0 1202 3 1 2 3 0 8 0 amappl1 72 16547 0 16073 26 13 13 20 0 8 3 amappl 80 670 0 625 2 0 2 2 0 84 1 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 18 0 17 1 0 1 1 0 8 0 aobjpl 64 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 285 0 268 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 285 0 268 1 0 1 1 0 8 0 vmmpekpl 168 6218 0 6189 2 0 2 2 0 8 0 vmmpepl 168 42532 0 40580 107 5 102 102 0 357 17 vmsppl 368 284 0 268 2 0 2 2 0 8 0 pdppl 4096 578 0 536 6 0 6 6 0 8 0 pvpl 32 156971 0 140543 165 0 165 165 0 265 26 pmappl 232 284 0 268 2 1 1 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 166 0 4 5 0 5 5 0 8 0