panic(ffffffff821f6c0d) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82680a00) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82680a00) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82680a00,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 ip_fragment(fffffd80692c7c00,ffff80000017b2a8,5b4) at ip_fragment+0x13a sys/netinet/ip_output.c:680 ip_output(fffffd80692c7c00,0,fffffd806f6ea2a0,0,0,fffffd806f6ea230) at ip_output+0xfd7 sys/netinet/ip_output.c:499 udp_output(fffffd806f6ea230,fffffd80692c7c00,0,0) at udp_output+0x5af sys/netinet/udp_usrreq.c:1008 sosend(fffffd8074414b00,0,ffff80002318fb80,0,0,0) at sosend+0x671 sys/kern/uipc_socket.c:549 sendit(ffff800020ec6c48,10,ffff80002318fc60,0,ffff80002318fd40) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendto(ffff800020ec6c48,ffff80002318fcf8,ffff80002318fd40) at sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 syscall(ffff80002318fdc0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002318fdc0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x293067b9db0, count: 2 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 0xfffffd8074bc7e00+16 0x0!=0x9e3a1b64aba60818 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821f6c0d) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82680a00) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82680a00) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82680a00,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 ip_fragment(fffffd80692c7c00,ffff80000017b2a8,5b4) at ip_fragment+0x13a sys/netinet/ip_output.c:680 ip_output(fffffd80692c7c00,0,fffffd806f6ea2a0,0,0,fffffd806f6ea230) at ip_output+0xfd7 sys/netinet/ip_output.c:499 udp_output(fffffd806f6ea230,fffffd80692c7c00,0,0) at udp_output+0x5af sys/netinet/udp_usrreq.c:1008 sosend(fffffd8074414b00,0,ffff80002318fb80,0,0,0) at sosend+0x671 sys/kern/uipc_socket.c:549 sendit(ffff800020ec6c48,10,ffff80002318fc60,0,ffff80002318fd40) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendto(ffff800020ec6c48,ffff80002318fcf8,ffff80002318fd40) at sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 syscall(ffff80002318fdc0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002318fdc0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x293067b9db0, count: -13 ddb{0}> show registers rdi 0xffffffff8160fef7 db_enter+0x17 rsi 0xe52f __ALIGN_SIZE+0xd52f rbp 0xffff80002318f5f0 rbx 0xffff80002318f6a0 rdx 0xe530 __ALIGN_SIZE+0xd530 rcx 0xffff800020f6c000 rax 0xffff800020f6c000 r8 0xffffffff818d14bf kprintf+0x16f r9 0x1 r10 0x25 r11 0xe133788af3e6f6d0 r12 0x3000000008 r13 0xffff80002318f600 r14 0x100 r15 0x1 rip 0xffffffff8160fef8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002318f5e0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=324086 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020ec7878,0xffff800020ec6778 process=0xffff800020e927d0 user=0xffff80002318a000, vmspace=0xfffffd807f000170 estcpu=36, cpticks=6, pctcpu=0.0 user=0, sys=5, intr=1 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 7761 496315 14842 0 7 0 syz-executor.0 * 7761 324086 14842 0 7 0x4000000 syz-executor.0 7761 394218 14842 0 2 0x4000000 syz-executor.0 19371 330504 15812 0 3 0x2 biowait syz-executor.1 14842 479377 15812 0 3 0x82 nanosleep syz-executor.0 15812 80265 27686 0 3 0x82 kqread syz-fuzzer 15812 428604 27686 0 3 0x4000082 nanosleep syz-fuzzer 15812 457409 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 34378 27686 0 3 0x4000082 nanosleep syz-fuzzer 15812 414329 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 81710 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 210463 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 273702 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 467154 27686 0 3 0x4000082 thrsleep syz-fuzzer 15812 244035 27686 0 3 0x4000082 thrsleep syz-fuzzer 27686 300092 39957 0 3 0x10008a pause ksh 39957 33974 86310 0 3 0x92 select sshd 36468 368995 1 0 3 0x100083 ttyin getty 86310 419295 1 0 3 0x80 select sshd 75422 305803 5470 74 3 0x100092 bpf pflogd 5470 289904 1 0 3 0x80 netio pflogd 88463 199174 7726 73 3 0x100090 kqread syslogd 7726 71755 1 0 3 0x100082 netio syslogd 4597 417398 1 77 3 0x100090 poll dhclient 5708 357049 1 0 3 0x80 poll dhclient 81170 354282 0 0 3 0x14200 bored smr 81102 34246 0 0 2 0x14200 zerothread 7881 376170 0 0 3 0x14200 aiodoned aiodoned 74427 97740 0 0 3 0x14200 syncer update 1641 390155 0 0 3 0x14200 cleaner cleaner 73076 473603 0 0 3 0x14200 reaper reaper 67433 516660 0 0 3 0x14200 pgdaemon pagedaemon 46525 100154 0 0 3 0x14200 bored crynlk 18022 521506 0 0 3 0x14200 bored crypto 47253 210008 0 0 3 0x40014200 acpi0 acpi0 10780 42121 0 0 3 0x40014200 idle1 76000 100360 0 0 3 0x14200 bored softnet 21558 296111 0 0 3 0x14200 bored systqmp 17771 504908 0 0 3 0x14200 bored systq 56150 124591 0 0 3 0x40014200 bored softclock 73718 482388 0 0 3 0x40014200 idle0 1 504999 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 7761 (syz-executor.0) thread 0xffff800020ec6c48 (324086) exclusive rwlock netlock r = 0 (0xffffffff824fd908) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x559 sys/kern/uipc_socket.c:537 #3 sendit+0x52b sys/kern/uipc_syscalls.c:657 #4 sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 #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 Process 19371 (syz-executor.1) thread 0xffff800020e6dd48 (330504) exclusive rrwlock inode r = 0 (0xfffffd806b45db38) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 ufs_ihashins+0x45 sys/ufs/ufs/ufs_ihash.c:140 #4 ffs_vget+0x13e sys/ufs/ffs/ffs_vfsops.c:1358 #5 ffs_inode_alloc+0x1cf sys/ufs/ffs/ffs_alloc.c:392 #6 ufs_mkdir+0xf4 sys/ufs/ufs/ufs_vnops.c:1162 #7 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #8 domkdirat+0x121 sys/kern/vfs_syscalls.c:3051 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #10 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806b45d1a8) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:575 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 domkdirat+0x75 sys/kern/vfs_syscalls.c:3036 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #9 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9486 6404K 6534K 78643K 10643 0 pcb 14 8K 8K 78643K 95 0 rtable 105 3K 3K 78643K 203 0 ifaddr 53 11K 12K 78643K 59 0 counters 43 33K 33K 78643K 43 0 ioctlops 0 0K 4K 78643K 1475 0 iov 0 0K 12K 78643K 21 0 mount 1 1K 1K 78643K 1 0 vnodes 1219 77K 77K 78643K 1247 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 3 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 18 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 98 0 proc 61 63K 83K 78643K 450 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 6 0 in_multi 33 2K 2K 78643K 43 0 ether_multi 1 0K 0K 78643K 5 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 227 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 93 21K 21K 78643K 1206 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 16 0 NDP 8 0K 0K 78643K 12 0 temp 78 3036K 3102K 78643K 2896 0 kqueue 3 4K 9K 78643K 12 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 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 21 0 19 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 61 0 46 1 0 1 1 0 8 0 syncache 264 5 0 5 2 1 1 1 0 8 1 tcpqe 32 41 0 41 1 0 1 1 0 8 1 tcpcb 544 44 0 39 1 0 1 1 0 8 0 inpcb 280 213 0 200 2 0 2 2 0 8 1 nd6 48 6 0 0 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 14 0 0 1 0 1 1 0 8 0 pfstkey 112 14 0 0 1 0 1 1 0 8 0 pfstate 328 14 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 256 189 0 0 12 0 12 12 0 8 0 art_table 32 190 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 12 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1515 0 107 46 0 46 46 0 8 0 ffsino 272 1515 0 107 95 0 95 95 0 8 1 nchpl 144 1828 0 213 61 0 61 61 0 8 0 uvmvnodes 72 1576 0 0 29 0 29 29 0 8 0 vnodes 208 1576 0 0 83 0 83 83 0 8 0 namei 1024 4720 0 4719 1 0 1 1 0 8 0 percpumem 16 32 0 0 1 0 1 1 0 8 0 vmpool 560 2 0 2 1 0 1 1 0 8 1 scxspl 192 5369 0 5368 2 1 1 2 0 8 0 plimitpl 152 17 0 9 1 0 1 1 0 8 0 sigapl 424 313 0 282 4 0 4 4 0 8 0 futexpl 56 1190 0 1190 1 0 1 1 0 8 1 knotepl 112 63 0 44 1 0 1 1 0 8 0 kqueuepl 144 20 0 18 1 0 1 1 0 8 0 pipelkpl 48 76 0 66 1 0 1 1 0 8 0 pipepl 120 152 0 133 1 0 1 1 0 8 0 fdescpl 496 298 0 282 3 0 3 3 0 8 0 filepl 152 1575 0 1464 5 0 5 5 0 8 0 lockfpl 104 19 0 18 1 0 1 1 0 8 0 lockfspl 48 8 0 7 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 20 0 9 1 0 1 1 0 8 0 ucredpl 96 78 0 69 1 0 1 1 0 8 0 zombiepl 144 282 0 282 1 0 1 1 0 8 1 processpl 984 313 0 282 5 0 5 5 0 8 0 procpl 624 467 0 425 4 0 4 4 0 8 0 sockpl 400 297 0 267 4 0 4 4 0 8 0 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 148 0 0 18 0 18 18 0 8 0 mtagpl 80 2 0 0 1 0 1 1 0 8 0 mbufpl 256 176 0 0 11 0 11 11 0 8 0 bufpl 280 4224 0 173 290 0 290 290 0 8 0 anonpl 16 42338 0 27336 62 1 61 61 0 124 0 amapchunkpl 152 1358 0 1229 8 0 8 8 0 158 2 amappl16 192 1267 0 446 42 0 42 42 0 8 0 amappl15 184 1 0 1 1 1 0 1 0 8 0 amappl14 176 2 0 2 2 2 0 1 0 8 0 amappl13 168 63 0 60 1 0 1 1 0 8 0 amappl12 160 34 0 31 2 1 1 1 0 8 0 amappl11 152 73 0 54 1 0 1 1 0 8 0 amappl10 144 23 0 19 1 0 1 1 0 8 0 amappl9 136 390 0 387 1 0 1 1 0 8 0 amappl8 128 293 0 279 1 0 1 1 0 8 0 amappl7 120 118 0 107 1 0 1 1 0 8 0 amappl6 112 23 0 20 1 0 1 1 0 8 0 amappl5 104 196 0 180 1 0 1 1 0 8 0 amappl4 96 535 0 504 2 1 1 2 0 8 0 amappl3 88 107 0 99 1 0 1 1 0 8 0 amappl2 80 1497 0 1424 3 1 2 3 0 8 0 amappl1 72 16529 0 16081 25 10 15 20 0 8 5 amappl 80 711 0 669 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 18 0 17 1 0 1 1 0 8 0 aobjpl 64 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 300 0 284 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 300 0 284 1 0 1 1 0 8 0 vmmpekpl 168 6155 0 6122 2 0 2 2 0 8 0 vmmpepl 168 43413 0 41454 110 5 105 105 0 357 19 vmsppl 368 299 0 284 2 0 2 2 0 8 0 pdppl 4096 608 0 568 6 0 6 6 0 8 0 pvpl 32 146794 0 128665 152 0 152 152 0 265 5 pmappl 232 299 0 284 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 165 0 3 5 0 5 5 0 8 0