panic(ffffffff821fd204) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82689248,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800020ed7868,0,404c,ffff800020ed79e8) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806eb32648,0,ffff800020ed79e8,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:536 dofilewritev(ffff800020ed0280,4,ffff800020ed79e8,0,ffff800020ed7ad0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ed0280,ffff800020ed7a80,ffff800020ed7ad0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ed7b50) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed7b50) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd0d40, count: 4 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 pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd80646b8300+16 0x0!=0xc7bb8f573d015aa4 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821fd204) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82689248,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800020ed7868,0,404c,ffff800020ed79e8) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806eb32648,0,ffff800020ed79e8,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:536 dofilewritev(ffff800020ed0280,4,ffff800020ed79e8,0,ffff800020ed7ad0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ed0280,ffff800020ed7a80,ffff800020ed7ad0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ed7b50) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed7b50) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd0d40, count: -11 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020ed7590 rbx 0xffff800020ed7640 rdx 0xffff800020ed0280 rcx 0 rax 0 r8 0xffffffff8101076f kprintf+0x16f r9 0x1 r10 0x25 r11 0x8fa2831ef79f2494 r12 0x3000000008 r13 0xffff800020ed75a0 r14 0x100 r15 0x1 rip 0xffffffff81ef7338 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020ed7580 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (sshd) pid=203050 stat=onproc flags process=12 proc=0 pri=24, usrpri=53, nice=20 forw=0xffffffffffffffff, list=0xffff800020ed04f0,0xffff800020ed0ec0 process=0xffff800020ec87c8 user=0xffff800020ed2000, vmspace=0xfffffd806e945738 estcpu=3, cpticks=14, pctcpu=0.0 user=0, sys=14, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 96586 74497 46894 0 2 0 syz-executor.0 46957 141194 0 0 3 0x14200 bored sosplice 77188 354976 41372 0 2 0x2 syz-executor.1 46894 470457 41372 0 2 0x482 syz-executor.0 41372 52304 33303 0 3 0x82 thrsleep syz-fuzzer 41372 26956 33303 0 2 0x4000482 syz-fuzzer 41372 503175 33303 0 3 0x4000082 thrsleep syz-fuzzer 41372 192122 33303 0 2 0x4000482 syz-fuzzer 41372 486586 33303 0 3 0x4000082 thrsleep syz-fuzzer 41372 436336 33303 0 3 0x4000082 thrsleep syz-fuzzer 41372 191999 33303 0 2 0x4000482 syz-fuzzer 41372 112850 33303 0 3 0x4000082 thrsleep syz-fuzzer 41372 205026 33303 0 3 0x4000082 thrsleep syz-fuzzer 41372 414152 33303 0 7 0x4000002 syz-fuzzer 33303 167597 38439 0 3 0x10008a pause ksh *38439 203050 13870 0 7 0x12 sshd 58697 423509 1 0 3 0x100083 ttyin getty 13870 465350 1 0 3 0x80 select sshd 84941 241442 58422 74 3 0x100092 bpf pflogd 58422 59469 1 0 3 0x80 netio pflogd 57049 80891 85171 73 3 0x100090 kqread syslogd 85171 313575 1 0 3 0x100082 netio syslogd 3944 440875 1 77 3 0x100090 poll dhclient 23037 210208 1 0 3 0x80 poll dhclient 1417 372308 0 0 3 0x14200 bored smr 51751 69638 0 0 2 0x14200 zerothread 55816 126377 0 0 3 0x14200 aiodoned aiodoned 62082 494727 0 0 3 0x14200 syncer update 73986 458664 0 0 3 0x14200 cleaner cleaner 16625 149453 0 0 3 0x14200 reaper reaper 68077 157300 0 0 3 0x14200 pgdaemon pagedaemon 55933 206744 0 0 3 0x14200 bored crynlk 41614 23070 0 0 3 0x14200 bored crypto 27883 93466 0 0 3 0x40014200 acpi0 acpi0 87572 342423 0 0 3 0x40014200 idle1 83112 71646 0 0 3 0x14200 bored softnet 20654 13743 0 0 3 0x14200 bored systqmp 77663 341 0 0 3 0x14200 bored systq 75568 262761 0 0 3 0x40014200 bored softclock 45712 397058 0 0 3 0x40014200 idle0 1 374365 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 41372 (syz-fuzzer) thread 0xffff800020e6c758 (414152) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8268c1d0) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 uvm_map_inentry+0xbe sys/uvm/uvm_map.c:1890 #2 syscall+0x397 mi_syscall sys/sys/syscall_mi.h:81 [inline] #2 syscall+0x397 sys/arch/amd64/amd64/trap.c:570 #3 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9511 6413K 6800K 78643K 10942 0 pcb 13 8K 8K 78643K 73 0 rtable 118 4K 4K 78643K 249 0 ifaddr 77 15K 16K 78643K 101 0 counters 43 33K 34K 78643K 49 0 ioctlops 0 0K 4K 78643K 1481 0 iov 0 0K 24K 78643K 31 0 mount 1 1K 1K 78643K 1 0 vnodes 1225 77K 77K 78643K 1347 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 6 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 24 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 276 0 sigio 0 0K 0K 78643K 6 0 proc 61 63K 95K 78643K 481 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 23 0 in_multi 68 3K 3K 78643K 96 0 ether_multi 1 0K 0K 78643K 12 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 43 201K 201K 78643K 43 0 exec 0 0K 1K 78643K 229 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 122 23K 23K 78643K 1823 0 UVM aobj 19 2K 2K 78643K 19 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 53 0 NDP 11 0K 0K 78643K 18 0 temp 94 3037K 3133K 78643K 7540 0 kqueue 3 4K 10K 78643K 45 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 8 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 43 0 41 1 0 1 1 0 8 0 rtentry 112 50 0 1 2 0 2 2 0 8 0 unpcb 120 367 0 357 1 0 1 1 0 8 0 syncache 264 6 0 6 2 2 0 1 0 8 0 tcpqe 32 78 0 78 1 1 0 1 0 8 0 tcpcb 544 111 0 107 1 0 1 1 0 8 0 inpcb 280 337 0 330 3 1 2 2 0 8 1 nd6 48 6 0 0 1 0 1 1 0 8 0 ppxss 1128 2 0 2 1 1 0 1 0 8 0 pffrag 232 3 0 3 2 1 1 1 0 482 1 pffrnode 88 3 0 3 2 1 1 1 0 8 1 pffrent 40 8 0 8 2 1 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 34 0 5 1 0 1 1 0 8 0 pfstkey 112 34 0 5 1 0 1 1 0 8 0 pfstate 328 34 0 5 3 0 3 3 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 207 0 0 13 0 13 13 0 8 0 art_table 32 209 0 0 2 0 2 2 0 8 0 art_node 16 49 0 4 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 18 0 8 1 0 1 1 0 8 0 shmpl 112 17 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1787 0 383 89 0 89 89 0 8 0 ffsino 272 1787 0 383 94 0 94 94 0 8 0 nchpl 144 2438 0 831 60 0 60 60 0 8 0 uvmvnodes 72 1915 0 0 35 0 35 35 0 8 0 vnodes 208 1915 0 0 101 0 101 101 0 8 0 namei 1024 6523 0 6523 1 0 1 1 0 8 1 percpumem 16 35 0 3 1 0 1 1 0 8 0 vmpool 560 2 0 2 1 1 0 1 0 8 0 scxspl 192 6361 0 6361 6 3 3 3 0 8 3 plimitpl 152 41 0 33 1 0 1 1 0 8 0 sigapl 424 492 0 460 4 0 4 4 0 8 0 futexpl 56 4343 0 4343 1 0 1 1 0 8 1 knotepl 112 106 0 87 1 0 1 1 0 8 0 kqueuepl 144 234 0 230 1 0 1 1 0 8 0 pipelkpl 48 103 0 93 1 0 1 1 0 8 0 pipepl 120 206 0 187 1 0 1 1 0 8 0 fdescpl 496 476 0 460 3 0 3 3 0 8 0 filepl 152 3062 0 2962 5 0 5 5 0 8 1 lockfpl 104 52 0 51 1 0 1 1 0 8 0 lockfspl 48 19 0 18 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 37 0 26 1 0 1 1 0 8 0 ucredpl 96 266 0 257 1 0 1 1 0 8 0 zombiepl 144 460 0 460 1 0 1 1 0 8 1 processpl 984 492 0 460 5 0 5 5 0 8 0 procpl 624 1044 0 1003 4 0 4 4 0 8 0 sosppl 128 5 0 5 1 1 0 1 0 8 0 sockpl 400 748 0 729 4 1 3 4 0 8 1 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl12k 12288 5 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 188 0 0 23 0 23 23 0 8 0 mtagpl 80 13 0 0 1 0 1 1 0 8 0 mbufpl 256 344 0 0 20 0 20 20 0 8 0 bufpl 280 3778 0 134 261 0 261 261 0 8 0 anonpl 16 62044 0 47148 82 1 81 81 0 124 14 amapchunkpl 152 2441 0 2308 10 1 9 9 0 158 3 amappl16 192 2252 0 1369 57 4 53 57 0 8 8 amappl15 184 9 0 8 2 1 1 1 0 8 0 amappl14 176 22 0 18 1 0 1 1 0 8 0 amappl13 168 149 0 146 1 0 1 1 0 8 0 amappl12 160 15 0 9 1 0 1 1 0 8 0 amappl11 152 58 0 42 1 0 1 1 0 8 0 amappl10 144 25 0 21 1 0 1 1 0 8 0 amappl9 136 508 0 506 1 0 1 1 0 8 0 amappl8 128 477 0 439 2 0 2 2 0 8 0 amappl7 120 119 0 106 1 0 1 1 0 8 0 amappl6 112 30 0 21 1 0 1 1 0 8 0 amappl5 104 375 0 359 1 0 1 1 0 8 0 amappl4 96 606 0 578 1 0 1 1 0 8 0 amappl3 88 110 0 105 1 0 1 1 0 8 0 amappl2 80 2874 0 2805 2 0 2 2 0 8 0 amappl1 72 20215 0 19776 24 15 9 18 0 8 0 amappl 80 1297 0 1253 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 18 0 0 1 0 1 1 0 8 0 uaddrrnd 24 478 0 462 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 478 0 462 1 0 1 1 0 8 0 vmmpekpl 168 7429 0 7394 2 0 2 2 0 8 0 vmmpepl 168 64670 0 62631 116 10 106 106 0 357 16 vmsppl 368 477 0 462 2 0 2 2 0 8 0 pdppl 4096 964 0 924 6 0 6 6 0 8 0 pvpl 32 225083 0 207046 196 0 196 196 0 265 38 pmappl 232 477 0 462 2 1 1 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 269 0 4 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffffffff824d2ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639 comintr(ffff80000065b000) at comintr+0x148 com_read_reg sys/dev/ic/com.c:1588 [inline] comintr(ffff80000065b000) at comintr+0x148 sys/dev/ic/com.c:1059 intr_handler(ffff800020f37380,ffff80000065ad80) at intr_handler+0x8f sys/arch/amd64/amd64/intr.c:529 Xintr_ioapic_edge4_untramp() at Xintr_ioapic_edge4_untramp+0x19f Xspllower() at Xspllower+0x19 tsleep(fffffd806e97bd80,118,ffffffff8224d2f6,0) at tsleep+0x162 sys/kern/kern_synch.c:141 kqueue_sleep(fffffd806e97bd80,0) at kqueue_sleep+0x1a0 sys/kern/kern_event.c:860 kqueue_scan(fffffd806e97bd80,40,c00028f698,0,ffff800020e6c758,ffff800020f3798c) at kqueue_scan+0x2b6 sys/kern/kern_event.c:903 sys_kevent(ffff800020e6c758,ffff800020f37a00,ffff800020f37a50) at sys_kevent+0x464 sys/kern/kern_event.c:615 syscall(ffff800020f37ad0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020f37ad0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00028fe98, count: 1 ddb{0}> trace x86_ipi_db(ffffffff824d2ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639 comintr(ffff80000065b000) at comintr+0x148 com_read_reg sys/dev/ic/com.c:1588 [inline] comintr(ffff80000065b000) at comintr+0x148 sys/dev/ic/com.c:1059 intr_handler(ffff800020f37380,ffff80000065ad80) at intr_handler+0x8f sys/arch/amd64/amd64/intr.c:529 Xintr_ioapic_edge4_untramp() at Xintr_ioapic_edge4_untramp+0x19f Xspllower() at Xspllower+0x19 tsleep(fffffd806e97bd80,118,ffffffff8224d2f6,0) at tsleep+0x162 sys/kern/kern_synch.c:141 kqueue_sleep(fffffd806e97bd80,0) at kqueue_sleep+0x1a0 sys/kern/kern_event.c:860 kqueue_scan(fffffd806e97bd80,40,c00028f698,0,ffff800020e6c758,ffff800020f3798c) at kqueue_scan+0x2b6 sys/kern/kern_event.c:903 sys_kevent(ffff800020e6c758,ffff800020f37a00,ffff800020f37a50) at sys_kevent+0x464 sys/kern/kern_event.c:615 syscall(ffff800020f37ad0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020f37ad0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00028fe98, count: -14 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x18: addq $0x8,%rsp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821fd204) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82689248,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800020ed7868,0,404c,ffff800020ed79e8) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806eb32648,0,ffff800020ed79e8,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:536 dofilewritev(ffff800020ed0280,4,ffff800020ed79e8,0,ffff800020ed7ad0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ed0280,ffff800020ed7a80,ffff800020ed7ad0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ed7b50) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed7b50) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd0d40, count: 4 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821fd204) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82689248) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82689248,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800020ed7868,0,404c,ffff800020ed79e8) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806eb32648,0,ffff800020ed79e8,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:536 dofilewritev(ffff800020ed0280,4,ffff800020ed79e8,0,ffff800020ed7ad0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ed0280,ffff800020ed7a80,ffff800020ed7ad0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ed7b50) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed7b50) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd0d40, count: -11