panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806f0aed00+16 0x0!=0x658f65132a7e2360 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *408213 29820 0 0x12 0 1 sshd 418076 67260 0 0x14000 0x200 0 softnet db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff8261fd98) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff8261fd98) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get() 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(ffff800020aeb148,0,1b48,ffff800020aeb2c8) at m_getuio+0xe4 sys/kern/uipc_socket.c:556 sosend(fffffd806e97d608,0,ffff800020aeb2c8,0,0,80) at sosend+0x510 sys/kern/uipc_socket.c:511 dofilewritev(ffff800020ac18c0,4,ffff800020aeb2c8,0,ffff800020aeb3b0) at dofilewritev+0x1b7 sys/kern/sys_generic.c:364 sys_write(ffff800020ac18c0,ffff800020aeb360,ffff800020aeb3b0) at sys_write+0x83 sys/kern/sys_generic.c:284 syscall(ffff800020aeb430) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020aeb430) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,4,d33e871616b,4,4,d361b612600) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe2fb0, 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 0xfffffd806f0aed00+16 0x0!=0x658f65132a7e2360 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 pool_cache_get(ffffffff8261fd98) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff8261fd98) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get() 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(ffff800020aeb148,0,1b48,ffff800020aeb2c8) at m_getuio+0xe4 sys/kern/uipc_socket.c:556 sosend(fffffd806e97d608,0,ffff800020aeb2c8,0,0,80) at sosend+0x510 sys/kern/uipc_socket.c:511 dofilewritev(ffff800020ac18c0,4,ffff800020aeb2c8,0,ffff800020aeb3b0) at dofilewritev+0x1b7 sys/kern/sys_generic.c:364 sys_write(ffff800020ac18c0,ffff800020aeb360,ffff800020aeb3b0) at sys_write+0x83 sys/kern/sys_generic.c:284 syscall(ffff800020aeb430) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020aeb430) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,4,d33e871616b,4,4,d361b612600) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe2fb0, count: -11 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020aeae80 rbx 0xffff800020aeaf30 rdx 0xffff800020ac18c0 rcx 0 rax 0 r8 0xffffffff819b290f kprintf+0x16f r9 0x1 r10 0x25 r11 0x161064ec6820459b r12 0x3000000008 r13 0xffff800020aeae90 r14 0x100 r15 0x1 rip 0xffffffff81ec7538 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020aeae70 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (sshd) pid=408213 stat=onproc flags process=12 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020ac1648,0xffff800020ac0c78 process=0xffff800020a8bc10 user=0xffff800020ae6000, vmspace=0xfffffd806e7dd008 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 46859 42833 53515 0 2 0 syz-executor.0 46859 419107 53515 0 3 0x4000080 select syz-executor.0 46859 422855 53515 0 3 0x4000080 fifor syz-executor.0 46859 285211 53515 0 3 0x4000080 fsleep syz-executor.0 9009 436756 10920 0 3 0x82 piperd syz-executor.1 53515 128067 10920 0 3 0x82 nanosleep syz-executor.0 38623 490008 1 0 3 0x100083 ttyin getty 3484 187869 0 0 3 0x14200 bored sosplice 10920 438300 99772 0 3 0x82 kqread syz-fuzzer 10920 185585 99772 0 3 0x4000082 nanosleep syz-fuzzer 10920 146622 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 373536 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 87044 99772 0 2 0x4000002 syz-fuzzer 10920 280432 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 318664 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 438843 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 451659 99772 0 3 0x4000082 thrsleep syz-fuzzer 10920 428301 99772 0 3 0x4000082 thrsleep syz-fuzzer 99772 168629 29820 0 3 0x10008a pause ksh *29820 408213 13245 0 7 0x12 sshd 13245 338582 1 0 3 0x80 select sshd 93046 251709 62551 74 3 0x100092 bpf pflogd 62551 221706 1 0 3 0x80 netio pflogd 29375 362724 3989 73 3 0x100090 kqread syslogd 3989 463831 1 0 3 0x100082 netio syslogd 16720 228794 1 77 3 0x100090 poll dhclient 48239 145263 1 0 3 0x80 poll dhclient 12551 296779 0 0 2 0x14200 zerothread 71427 263364 0 0 3 0x14200 aiodoned aiodoned 23096 98730 0 0 3 0x14200 syncer update 5678 464678 0 0 3 0x14200 cleaner cleaner 42409 436745 0 0 3 0x14200 reaper reaper 86401 123875 0 0 3 0x14200 pgdaemon pagedaemon 48909 147963 0 0 3 0x14200 bored crynlk 74797 198197 0 0 3 0x14200 bored crypto 72624 60269 0 0 3 0x40014200 acpi0 acpi0 65785 435965 0 0 3 0x40014200 idle1 67260 418076 0 0 7 0x14200 softnet 84727 222537 0 0 3 0x14200 bored systqmp 87719 344246 0 0 3 0x14200 bored systq 78205 328221 0 0 3 0x40014200 bored softclock 28352 421334 0 0 3 0x40014200 idle0 80636 47937 0 0 3 0x14200 bored smr 1 448250 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 10920 (syz-fuzzer) thread 0xffff800020abf8c8 (451659) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8265c400) #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{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9611 7106K 7754K 78643K 19386 0 0 pcb 13 12K 14K 78643K 677 0 0 rtable 99 13K 14K 78643K 2722 0 0 ifaddr 95 21K 22K 78643K 953 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1644 0 0 iov 0 0K 24K 78643K 756 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1212 76K 77K 78643K 4682 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 37 0 0 VM map 2 1K 1K 78643K 27 0 0 sem 12 0K 0K 78643K 724 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 3870 0 0 sigio 0 0K 0K 78643K 91 0 0 proc 62 63K 83K 78643K 1638 0 0 subproc 32 2K 2K 78643K 374 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 326 0 0 in_multi 24 1K 2K 78643K 409 0 0 ether_multi 1 0K 0K 78643K 26 0 0 mrt 0 0K 0K 78643K 16 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 84 371K 371K 78643K 84 0 0 exec 0 0K 1K 78643K 861 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 118 22K 32K 78643K 14672 0 0 UVM aobj 130 4K 4K 78643K 149 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 1K 78643K 773 0 0 NDP 23 0K 1K 78643K 286 0 0 temp 250 3561K 4207K 78643K 111481 0 0 kqueue 0 0K 0K 78643K 33 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 80 0 77 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 263 0 261 1 0 1 1 0 8 0 rtentry 112 388 0 356 2 0 2 2 0 8 0 unpcb 120 8966 0 8950 15 13 2 3 0 8 0 syncache 264 13 0 13 7 7 0 1 0 8 0 tcpqe 32 5820 0 5820 2 2 0 1 0 8 0 tcpcb 544 6082 0 6076 47 44 3 12 0 8 2 inpcb 280 9045 0 9036 41 33 8 13 0 8 7 rttmr 72 5 0 4 4 3 1 1 0 8 0 nd6 48 53 0 51 2 1 1 1 0 8 0 pkpcb 40 12 0 12 7 6 1 1 0 8 1 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 163 0 163 15 14 1 1 0 8 1 pffrag 232 59 0 59 14 14 0 1 0 482 0 pffrnode 88 59 0 59 14 14 0 1 0 8 0 pffrent 40 817 0 817 14 14 0 1 0 8 0 pfosfp 40 846 0 846 5 5 0 5 0 8 0 pfosfpen 112 1428 0 1428 21 21 0 21 0 8 0 pfstitem 24 279 0 240 1 0 1 1 0 8 0 pfstkey 112 279 0 240 2 0 2 2 0 8 0 pfstate 328 279 0 240 6 0 6 6 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 6 0 5 5 4 1 3 0 8 0 art_heap4 256 1564 0 1370 33 20 13 15 0 8 0 art_table 32 1570 0 1375 2 0 2 2 0 8 0 art_node 16 385 0 356 1 0 1 1 0 8 0 sysvmsgpl 40 29 0 22 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 722 0 712 1 0 1 1 0 8 0 shmpl 112 147 0 19 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 7408 0 6001 46 0 46 46 0 8 0 ffsino 272 7408 0 6001 95 0 95 95 0 8 0 nchpl 144 13033 0 11419 61 0 61 61 0 8 0 uvmvnodes 72 6629 0 0 121 0 121 121 0 8 0 vnodes 208 6629 0 0 349 0 349 349 0 8 0 namei 1024 46345 0 46345 4 3 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vmpool 552 25 0 25 9 8 1 1 0 8 1 scsiplug 64 4 0 4 3 3 0 1 0 8 0 scxspl 192 41689 0 41689 44 41 3 7 0 8 3 plimitpl 152 348 0 340 1 0 1 1 0 8 0 sigapl 432 4012 0 3997 3 1 2 3 0 8 0 futexpl 56 99781 0 99780 1 0 1 1 0 8 0 knotepl 112 1693 0 1674 1 0 1 1 0 8 0 kqueuepl 104 2538 0 2536 10 9 1 4 0 8 0 pipepl 112 2356 0 2337 10 9 1 2 0 8 0 fdescpl 488 4013 0 3997 3 0 3 3 0 8 0 filepl 152 42726 0 42621 60 49 11 14 0 8 6 lockfpl 104 1185 0 1184 1 0 1 1 0 8 0 lockfspl 48 395 0 394 1 0 1 1 0 8 0 sessionpl 112 40 0 29 1 0 1 1 0 8 0 pgrppl 48 97 0 86 1 0 1 1 0 8 0 ucredpl 96 4440 0 4431 1 0 1 1 0 8 0 zombiepl 144 4001 0 4001 3 2 1 1 0 8 1 processpl 896 4033 0 4001 4 0 4 4 0 8 0 procpl 632 12838 0 12794 7 2 5 5 0 8 1 srpgc 64 32 0 32 12 12 0 1 0 8 0 sosppl 128 56 0 56 15 14 1 1 0 8 1 sockpl 384 18336 0 18309 103 92 11 22 0 8 7 mcl64k 65536 261 0 0 33 0 33 33 0 8 0 mcl16k 16384 17 0 0 3 0 3 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 17 0 0 3 0 3 3 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 154 0 0 15 1 14 15 0 8 0 mtagpl 80 52 0 0 1 0 1 1 0 8 0 mbufpl 256 733 0 0 30 0 30 30 0 8 0 bufpl 256 20242 0 13194 441 0 441 441 0 8 0 anonpl 16 482845 0 467225 179 92 87 87 0 124 14 amapchunkpl 152 30768 0 30651 68 56 12 19 0 158 5 amappl16 192 21662 0 20654 165 106 59 63 0 8 7 amappl15 184 993 0 993 3 2 1 1 0 8 1 amappl14 176 1165 0 1161 2 1 1 1 0 8 0 amappl13 168 482 0 481 5 4 1 1 0 8 0 amappl12 160 309 0 308 1 0 1 1 0 8 0 amappl11 152 335 0 320 1 0 1 1 0 8 0 amappl10 144 20 0 17 1 0 1 1 0 8 0 amappl9 136 1356 0 1350 1 0 1 1 0 8 0 amappl8 128 888 0 854 2 0 2 2 0 8 0 amappl7 120 133 0 125 1 0 1 1 0 8 0 amappl6 112 335 0 323 1 0 1 1 0 8 0 amappl5 104 655 0 641 1 0 1 1 0 8 0 amappl4 96 3950 0 3915 1 0 1 1 0 8 0 amappl3 88 2036 0 2029 1 0 1 1 0 8 0 amappl2 80 30481 0 30405 4 2 2 3 0 8 0 amappl1 72 100420 0 99978 25 15 10 20 0 8 0 amappl 80 13470 0 13429 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 64 148 0 19 3 0 3 3 0 8 0 uaddrrnd 24 4038 0 3997 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4038 0 3997 1 0 1 1 0 8 0 vmmpekpl 168 34562 0 34527 2 0 2 2 0 8 0 vmmpepl 168 509792 0 507632 314 180 134 134 0 357 34 vmsppl 368 4012 0 3997 2 0 2 2 0 8 0 pdppl 4096 8083 0 8044 7 1 6 6 0 8 0 pvpl 32 1234451 0 1215574 365 159 206 208 0 265 35 pmappl 232 4037 0 4022 9 8 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 729 0 77 19 0 19 19 0 8 0