panic: pool_cache_item_magic_check: mcl2k cpu free list modified: item addr 0xfffffd807b1eb000+16 0x0!=0x96080d92d7d3772 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *149322 27685 0 0 0x4000000 0K syz-executor.0 51477 97037 0 0x14000 0x200 1 reaper db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821c4d4c) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82624910) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff82624910) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get(ffffffff82624910,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_clget(fffffd806d6d6500,2,800) at m_clget+0x2d0 sys/kern/uipc_mbuf.c:407 tcp_output(ffff8000009f6ee0) at tcp_output+0x16bd sys/netinet/tcp_output.c:706 tcp_usrreq(fffffd806ca85018,4,0,fffffd806f29bd00,0,ffff800020adf3e0) at tcp_usrreq+0xa45 sys_connect(ffff800020adf3e0,ffff800023bb1d08,ffff800023bb1d50) at sys_connect+0x3df sys/kern/uipc_syscalls.c:388 syscall(ffff800023bb1dd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800023bb1dd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3191b24df70, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic pool_cache_item_magic_check: mcl2k cpu free list modified: item addr 0xfffffd807b1eb000+16 0x0!=0x96080d92d7d3772 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821c4d4c) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82624910) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff82624910) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get(ffffffff82624910,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_clget(fffffd806d6d6500,2,800) at m_clget+0x2d0 sys/kern/uipc_mbuf.c:407 tcp_output(ffff8000009f6ee0) at tcp_output+0x16bd sys/netinet/tcp_output.c:706 tcp_usrreq(fffffd806ca85018,4,0,fffffd806f29bd00,0,ffff800020adf3e0) at tcp_usrreq+0xa45 sys_connect(ffff800020adf3e0,ffff800023bb1d08,ffff800023bb1d50) at sys_connect+0x3df sys/kern/uipc_syscalls.c:388 syscall(ffff800023bb1dd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800023bb1dd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3191b24df70, count: -10 ddb{0}> show registers rdi 0xffffffff819de877 db_enter+0x17 rsi 0x3ba9 __ALIGN_SIZE+0x2ba9 rbp 0xffff800023bb17e0 rbx 0xffff800023bb1890 rdx 0x3baa __ALIGN_SIZE+0x2baa rcx 0xffff800020b76000 rax 0xffff800020b76000 r8 0xffffffff81112b4f kprintf+0x16f r9 0x1 r10 0x25 r11 0xdb0a6cca2166939 r12 0x3000000008 r13 0xffff800023bb17f0 r14 0x100 r15 0x1 rip 0xffffffff819de878 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800023bb17d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=149322 stat=onproc flags process=0 proc=4000000 pri=60, usrpri=60, nice=20 forw=0xffffffffffffffff, list=0xffff800020ade510,0xffffffff82648cc0 process=0xffff800020a9b540 user=0xffff800023bac000, vmspace=0xfffffd806e7a4e68 estcpu=22, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 27685 34194 35449 0 2 0 syz-executor.0 *27685 149322 35449 0 7 0x4000000 syz-executor.0 50292 214608 31066 0 3 0x82 nanosleep syz-executor.1 35449 489819 31066 0 3 0x82 nanosleep syz-executor.0 31066 496558 3989 0 3 0x82 thrsleep syz-fuzzer 31066 386234 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 212915 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 29187 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 74551 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 146289 3989 0 3 0x4000082 kqread syz-fuzzer 31066 361169 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 114873 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 41421 3989 0 3 0x4000082 thrsleep syz-fuzzer 31066 87273 3989 0 3 0x4000082 thrsleep syz-fuzzer 3989 523563 4382 0 3 0x10008a pause ksh 4382 158344 47627 0 3 0x92 select sshd 85957 380917 1 0 3 0x100083 ttyin getty 47627 73244 1 0 3 0x80 select sshd 27498 460872 77535 74 3 0x100092 bpf pflogd 77535 203262 1 0 3 0x80 netio pflogd 56120 501243 16157 73 3 0x100090 kqread syslogd 16157 235820 1 0 3 0x100082 netio syslogd 89062 96734 1 77 3 0x100090 poll dhclient 58639 426 1 0 3 0x80 poll dhclient 70500 288641 0 0 2 0x14200 zerothread 46601 174897 0 0 3 0x14200 aiodoned aiodoned 63605 151570 0 0 3 0x14200 syncer update 70070 266529 0 0 3 0x14200 cleaner cleaner 97037 51477 0 0 7 0x14200 reaper 56510 42867 0 0 3 0x14200 pgdaemon pagedaemon 27731 113889 0 0 3 0x14200 bored crynlk 21517 150201 0 0 3 0x14200 bored crypto 18791 259990 0 0 3 0x40014200 acpi0 acpi0 4746 5360 0 0 3 0x40014200 idle1 40622 236188 0 0 3 0x14200 bored softnet 90652 63711 0 0 3 0x14200 bored systqmp 97137 516232 0 0 3 0x14200 bored systq 26103 395571 0 0 3 0x40014200 bored softclock 35028 238943 0 0 3 0x40014200 idle0 7149 390832 0 0 3 0x14200 bored smr 1 6223 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 1: exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff826064f8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 uvm_pmr_freepages+0x126 sys/uvm/uvm_pmemrange.c:1135 #4 pmap_do_remove+0x68b sys/arch/amd64/amd64/pmap.c:1799 #5 uvm_map_teardown+0x195 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:206 [inline] #5 uvm_map_teardown+0x195 sys/uvm/uvm_map.c:2725 #6 uvmspace_free+0x86 sys/uvm/uvm_map.c:3600 #7 uvm_exit+0x29 sys/uvm/uvm_glue.c:297 #8 reaper+0x189 sys/kern/kern_exit.c:442 #9 proc_trampoline+0x1c Process 27685 (syz-executor.0) thread 0xffff800020adf3e0 (149322) exclusive rwlock netlock r = 0 (0xffffffff82485568) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sys_connect+0x6b sys/kern/uipc_syscalls.c:362 #3 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #3 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #4 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff826071a0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 syscall+0x400 mi_syscall sys/sys/syscall_mi.h:83 [inline] #1 syscall+0x400 sys/arch/amd64/amd64/trap.c:555 #2 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9494 6414K 6664K 78643K 10760 0 pcb 13 8K 8K 78643K 41 0 rtable 108 4K 4K 78643K 219 0 ifaddr 59 12K 12K 78643K 73 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1471 0 iov 0 0K 16K 78643K 20 0 mount 1 1K 1K 78643K 1 0 vnodes 1214 76K 77K 78643K 1281 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 0K 78643K 24 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 113 0 proc 60 63K 95K 78643K 439 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 1 0 in_multi 40 2K 2K 78643K 40 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 36 159K 159K 78643K 36 0 exec 0 0K 1K 78643K 212 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 123 22K 31K 78643K 1330 0 UVM aobj 6 2K 2K 78643K 6 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 1 0K 0K 78643K 23 0 NDP 9 0K 0K 78643K 14 0 temp 101 3013K 3078K 78643K 3723 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 32 0 30 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 61 0 51 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 79 0 79 1 1 0 1 0 8 0 tcpcb 544 47 0 41 1 0 1 1 0 8 0 inpcb 280 185 0 175 2 0 2 2 0 8 1 nd6 48 4 0 0 1 0 1 1 0 8 0 ppxss 1128 1 0 1 1 0 1 1 0 8 1 pffrag 232 4 0 4 1 0 1 1 0 482 1 pffrnode 88 4 0 4 1 0 1 1 0 8 1 pffrent 40 180 0 180 1 0 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 20 0 0 1 0 1 1 0 8 0 pfstkey 112 20 0 0 1 0 1 1 0 8 0 pfstate 328 20 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 256 213 0 0 14 0 14 14 0 8 0 art_table 32 214 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 0 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 22 0 12 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1554 0 149 46 0 46 46 0 8 0 ffsino 272 1554 0 149 95 0 95 95 0 8 0 nchpl 144 1951 0 341 61 0 61 61 0 8 0 uvmvnodes 72 1642 0 0 30 0 30 30 0 8 0 vnodes 208 1642 0 0 87 0 87 87 0 8 0 namei 1024 5210 0 5210 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 5259 0 5259 8 1 7 7 0 8 7 plimitpl 152 27 0 19 1 0 1 1 0 8 0 sigapl 432 312 0 297 3 0 3 3 0 8 1 futexpl 56 2020 0 2020 1 0 1 1 0 8 1 knotepl 112 119 0 100 3 0 3 3 0 8 2 kqueuepl 104 160 0 158 1 0 1 1 0 8 0 pipepl 160 176 0 157 1 0 1 1 0 8 0 fdescpl 488 313 0 297 3 0 3 3 0 8 0 filepl 152 2077 0 1974 5 0 5 5 0 8 1 lockfpl 104 36 0 35 1 0 1 1 0 8 0 lockfspl 48 15 0 14 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 137 0 127 1 0 1 1 0 8 0 zombiepl 144 297 0 296 1 0 1 1 0 8 0 processpl 904 328 0 296 4 0 4 4 0 8 0 procpl 632 547 0 505 5 0 5 5 0 8 0 sockpl 384 280 0 258 5 1 4 4 0 8 1 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 176 0 0 21 0 21 21 0 8 0 mtagpl 80 7 0 0 1 0 1 1 0 8 0 mbufpl 256 233 0 0 15 0 15 15 0 8 0 bufpl 280 6368 0 1340 360 0 360 360 0 8 0 anonpl 16 48304 0 29148 81 1 80 80 0 125 3 amapchunkpl 152 1539 0 1378 11 1 10 10 0 158 3 amappl16 192 1407 0 361 53 0 53 53 0 8 0 amappl15 184 143 0 135 1 0 1 1 0 8 0 amappl14 176 28 0 25 1 0 1 1 0 8 0 amappl13 168 1 0 1 1 1 0 1 0 8 0 amappl12 160 14 0 10 1 0 1 1 0 8 0 amappl11 152 90 0 73 1 0 1 1 0 8 0 amappl10 144 9 0 6 1 0 1 1 0 8 0 amappl9 136 603 0 599 1 0 1 1 0 8 0 amappl8 128 131 0 103 2 0 2 2 0 8 0 amappl7 120 102 0 91 1 0 1 1 0 8 0 amappl6 112 94 0 84 1 0 1 1 0 8 0 amappl5 104 129 0 116 1 0 1 1 0 8 0 amappl4 96 566 0 534 1 0 1 1 0 8 0 amappl3 88 113 0 106 1 0 1 1 0 8 0 amappl2 80 1654 0 1568 3 1 2 3 0 8 0 amappl1 72 17017 0 16541 25 14 11 20 0 8 1 amappl 80 799 0 749 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 5 0 0 1 0 1 1 0 8 0 uaddrrnd 24 313 0 297 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 313 0 297 1 0 1 1 0 8 0 vmmpekpl 168 6297 0 6265 2 0 2 2 0 8 0 vmmpepl 168 46368 0 44047 134 4 130 130 0 357 27 vmsppl 368 312 0 296 2 0 2 2 0 8 0 pdppl 4096 633 0 592 6 0 6 6 0 8 0 pvpl 32 159270 0 137031 190 0 190 190 0 265 9 pmappl 232 312 0 296 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 171 0 3 5 0 5 5 0 8 0