panic: pr_find_pagehead: mbufpl: incorrect page Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821a9c2d) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_put(ffffffff8257aed0,fffffd8035000000) at pool_do_put+0x36a pool_put(ffffffff8257aed0,fffffd8035000000) at pool_put+0x4b sys/kern/subr_pool.c:802 m_free(fffffd8035000000) at m_free+0x119 sys/kern/uipc_mbuf.c:459 ml_purge(ffff800014951c58) at ml_purge+0x50 m_freem sys/kern/uipc_mbuf.c:538 [inline] ml_purge(ffff800014951c58) at ml_purge+0x50 sys/kern/uipc_mbuf.c:1628 ifq_purge(ffff8000009e3a78) at ifq_purge+0x97 sys/net/ifq.c:423 tapclose(5d00,7,2000,ffff8000ffff8c60) at tapclose+0xed tun_dev_close sys/net/if_tun.c:454 [inline] tapclose(5d00,7,2000,ffff8000ffff8c60) at tapclose+0xed sys/net/if_tun.c:433 spec_close(ffff800014951d70) at spec_close+0x311 sys/kern/spec_vnops.c:555 VOP_CLOSE(fffffd80360c8d00,7,fffffd803f7c6b40,ffff8000ffff8c60) at VOP_CLOSE+0xc0 sys/kern/vfs_vops.c:175 vn_closefile(fffffd802d665d30,ffff8000ffff8c60) at vn_closefile+0xd3 vn_close sys/kern/vfs_vnops.c:298 [inline] vn_closefile(fffffd802d665d30,ffff8000ffff8c60) at vn_closefile+0xd3 sys/kern/vfs_vnops.c:610 fdrop(fffffd802d665d30,ffff8000ffff8c60) at fdrop+0xc2 sys/kern/kern_descrip.c:1273 closef(fffffd802d665d30,ffff8000ffff8c60) at closef+0x118 sys/kern/kern_descrip.c:1257 fdfree(ffff8000ffff8c60) at fdfree+0x100 sys/kern/kern_descrip.c:1189 end trace frame: 0xffff800014951fc0, 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic pr_find_pagehead: mbufpl: incorrect page ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821a9c2d) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_put(ffffffff8257aed0,fffffd8035000000) at pool_do_put+0x36a pool_put(ffffffff8257aed0,fffffd8035000000) at pool_put+0x4b sys/kern/subr_pool.c:802 m_free(fffffd8035000000) at m_free+0x119 sys/kern/uipc_mbuf.c:459 ml_purge(ffff800014951c58) at ml_purge+0x50 m_freem sys/kern/uipc_mbuf.c:538 [inline] ml_purge(ffff800014951c58) at ml_purge+0x50 sys/kern/uipc_mbuf.c:1628 ifq_purge(ffff8000009e3a78) at ifq_purge+0x97 sys/net/ifq.c:423 tapclose(5d00,7,2000,ffff8000ffff8c60) at tapclose+0xed tun_dev_close sys/net/if_tun.c:454 [inline] tapclose(5d00,7,2000,ffff8000ffff8c60) at tapclose+0xed sys/net/if_tun.c:433 spec_close(ffff800014951d70) at spec_close+0x311 sys/kern/spec_vnops.c:555 VOP_CLOSE(fffffd80360c8d00,7,fffffd803f7c6b40,ffff8000ffff8c60) at VOP_CLOSE+0xc0 sys/kern/vfs_vops.c:175 vn_closefile(fffffd802d665d30,ffff8000ffff8c60) at vn_closefile+0xd3 vn_close sys/kern/vfs_vnops.c:298 [inline] vn_closefile(fffffd802d665d30,ffff8000ffff8c60) at vn_closefile+0xd3 sys/kern/vfs_vnops.c:610 fdrop(fffffd802d665d30,ffff8000ffff8c60) at fdrop+0xc2 sys/kern/kern_descrip.c:1273 closef(fffffd802d665d30,ffff8000ffff8c60) at closef+0x118 sys/kern/kern_descrip.c:1257 fdfree(ffff8000ffff8c60) at fdfree+0x100 sys/kern/kern_descrip.c:1189 exit1(ffff8000ffff8c60,19,1) at exit1+0x32f sys/kern/kern_exit.c:196 postsig(ffff8000ffff8c60,19) at postsig+0x4a6 sigexit sys/kern/kern_sig.c:1499 [inline] postsig(ffff8000ffff8c60,19) at postsig+0x4a6 sys/kern/kern_sig.c:1431 userret(ffff8000ffff8c60) at userret+0x159 sys/kern/kern_sig.c:1889 Xsyscall() at Xsyscall+0x156 end of kernel end trace frame: 0x7f7ffffe4400, count: -18 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014951a00 rbx 0xffff800014951ab0 rdx 0x2 rcx 0 rax 0 r8 0xffff8000149519c0 r9 0x1 r10 0 r11 0x8cb304a78b6daa40 r12 0x3000000008 r13 0xffff800014951a10 r14 0x100 r15 0x1 rip 0xffffffff81431e68 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000149519f0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.0) pid=207319 stat=onproc flags process=a proc=2000 pri=61, usrpri=61, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff8770,0xffffffff82545ea8 process=0xffff8000148b2378 user=0xffff80001494d000, vmspace=0xfffffd803f012bb0 estcpu=22, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 79609 62745 31248 0 2 0x2 syz-executor.1 31248 370514 70317 0 2 0x82 syz-fuzzer 31248 466228 70317 0 3 0x4000082 nanosleep syz-fuzzer 31248 142430 70317 0 3 0x4000082 thrsleep syz-fuzzer 31248 93731 70317 0 3 0x4000082 thrsleep syz-fuzzer 31248 53547 70317 0 3 0x4000082 thrsleep syz-fuzzer 31248 77841 70317 0 3 0x4000082 thrsleep syz-fuzzer 31248 206334 70317 0 3 0x4000082 thrsleep syz-fuzzer 70317 517211 43262 0 3 0x10008a pause ksh 43262 326078 73568 0 3 0x92 select sshd 6318 249856 1 0 3 0x100083 ttyin getty 73568 63982 1 0 3 0x80 select sshd 52290 55435 1396 73 3 0x100090 kqread syslogd 1396 299941 1 0 3 0x100082 netio syslogd 97940 408923 1 77 3 0x100090 poll dhclient 3554 425307 1 0 3 0x80 poll dhclient 19389 6441 0 0 2 0x14200 zerothread 87386 90213 0 0 3 0x14200 aiodoned aiodoned 53463 349906 0 0 3 0x14200 syncer update 29672 390961 0 0 3 0x14200 cleaner cleaner 88656 271362 0 0 3 0x14200 reaper reaper 37033 464456 0 0 3 0x14200 pgdaemon pagedaemon 86238 250112 0 0 3 0x14200 bored crynlk 92392 245765 0 0 3 0x14200 bored crypto 67408 468522 0 0 3 0x40014200 acpi0 acpi0 43057 89991 0 0 2 0x14200 softnet 672 363860 0 0 3 0x14200 bored systqmp 27007 90917 0 0 3 0x14200 bored systq 21240 256582 0 0 3 0x40014200 bored softclock 81421 473669 0 0 3 0x40014200 idle0 14337 10955 0 0 3 0x14200 bored smr 1 272826 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9492 6466K 6784K 78643K 10953 0 pcb 13 8K 8K 78643K 45 0 rtable 101 3K 4K 78643K 243 0 ifaddr 64 13K 13K 78643K 87 0 counters 19 16K 16K 78643K 19 0 ioctlops 0 0K 2K 78643K 23 0 iov 0 0K 16K 78643K 30 0 mount 1 1K 1K 78643K 1 0 vnodes 1217 76K 77K 78643K 1342 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 6 1K 1K 78643K 8 0 sem 12 0K 1K 78643K 54 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1794 195K 288K 78643K 12646 0 file desc 4 9K 25K 78643K 161 0 sigio 0 0K 0K 78643K 8 0 proc 48 38K 63K 78643K 373 0 subproc 23 1K 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 29 0 in_multi 54 2K 2K 78643K 65 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 36 159K 159K 78643K 36 0 exec 0 0K 1K 78643K 193 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 113 54K 54K 78643K 1248 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 0 0K 0K 78643K 34 0 NDP 10 0K 0K 78643K 16 0 temp 102 3008K 3074K 78643K 4245 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 2 1 0 1 1 0 8 0 rtpcb 80 21 0 19 1 0 1 1 0 8 0 rtentry 112 50 0 11 2 0 2 2 0 8 0 unpcb 120 245 0 237 2 0 2 2 0 8 1 syncache 264 4 0 4 2 2 0 1 0 8 0 tcpqe 32 151 0 151 1 1 0 1 0 8 0 tcpcb 544 76 0 72 1 0 1 1 0 8 0 ipq 40 6 0 6 1 0 1 1 0 8 1 ipqe 40 100 0 100 1 0 1 1 0 8 1 inpcb 280 204 0 197 2 0 2 2 0 8 1 nd6 48 5 0 2 1 0 1 1 0 8 0 ppxss 1128 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 260 0 43 14 0 14 14 0 8 0 art_table 32 262 0 43 2 0 2 2 0 8 0 art_node 16 49 0 13 1 0 1 1 0 8 0 sysvmsgpl 40 14 0 13 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 52 0 42 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 1629 0 234 46 0 46 46 0 8 0 ffsino 240 1629 0 234 83 0 83 83 0 8 0 nchpl 144 2062 0 451 60 0 60 60 0 8 0 uvmvnodes 72 1760 0 0 32 0 32 32 0 8 0 vnodes 208 1760 0 0 93 0 93 93 0 8 0 namei 1024 5341 0 5340 1 0 1 1 0 8 0 vcpupl 1984 4 0 0 1 0 1 1 0 8 0 vmpool 520 6 0 2 1 0 1 1 0 8 0 scxspl 192 5871 0 5871 8 5 3 7 0 8 3 plimitpl 152 26 0 19 1 0 1 1 0 8 0 sigapl 432 332 0 320 2 0 2 2 0 8 0 futexpl 56 3859 0 3859 1 0 1 1 0 8 1 knotepl 112 66 0 47 1 0 1 1 0 8 0 kqueuepl 104 28 0 26 1 0 1 1 0 8 0 pipepl 128 214 0 196 2 1 1 2 0 8 0 fdescpl 424 333 0 320 2 0 2 2 0 8 0 filepl 120 2277 0 2192 5 1 4 5 0 8 1 lockfpl 104 57 0 56 1 0 1 1 0 8 0 lockfspl 48 20 0 19 1 0 1 1 0 8 0 sessionpl 112 17 0 7 1 0 1 1 0 8 0 pgrppl 48 21 0 11 1 0 1 1 0 8 0 ucredpl 96 183 0 176 1 0 1 1 0 8 0 zombiepl 144 321 0 320 1 0 1 1 0 8 0 processpl 864 347 0 320 4 0 4 4 0 8 0 procpl 632 528 0 495 4 0 4 4 0 8 1 sockpl 384 470 0 453 5 0 5 5 0 8 3 mcl64k 65536 21 0 21 1 0 1 1 0 8 1 mcl12k 12288 5 0 5 1 1 0 1 0 8 0 mcl9k 9216 2 0 2 2 1 1 1 0 8 1 mcl8k 8192 6 0 6 1 0 1 1 0 8 1 mcl4k 4096 23 0 23 3 2 1 1 0 8 1 mcl2k2 2112 2 0 2 1 0 1 1 0 8 1 mcl2k 2048 70096 0 70055 15 6 9 13 0 8 3 mtagpl 80 7 0 7 2 1 1 1 0 8 1 mbufpl 256 112667 0 112599 23 10 13 20 0 8 8 bufpl 280 6669 0 1725 354 0 354 354 0 8 0 anonpl 16 50590 0 30456 85 2 83 83 0 62 0 amapchunkpl 152 1540 0 1393 9 2 7 9 0 158 0 amappl16 192 1784 0 669 58 0 58 58 0 8 1 amappl15 184 127 0 120 1 0 1 1 0 8 0 amappl14 176 25 0 24 1 0 1 1 0 8 0 amappl12 160 9 0 8 2 1 1 1 0 8 0 amappl11 152 47 0 36 1 0 1 1 0 8 0 amappl10 144 69 0 67 2 1 1 1 0 8 0 amappl9 136 562 0 559 1 0 1 1 0 8 0 amappl8 128 119 0 93 1 0 1 1 0 8 0 amappl7 120 160 0 148 1 0 1 1 0 8 0 amappl6 112 55 0 48 1 0 1 1 0 8 0 amappl5 104 139 0 127 1 0 1 1 0 8 0 amappl4 96 543 0 515 1 0 1 1 0 8 0 amappl3 88 126 0 118 1 0 1 1 0 8 0 amappl2 80 1921 0 1860 3 1 2 3 0 8 0 amappl1 72 15516 0 15116 27 18 9 20 0 8 0 amappl 80 771 0 728 1 0 1 1 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 24 339 0 320 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 339 0 320 1 0 1 1 0 8 0 vmmpekpl 168 6387 0 6361 2 0 2 2 0 8 0 vmmpepl 168 47968 0 45860 138 13 125 129 0 357 27 vmsppl 272 332 0 320 2 1 1 2 0 8 0 pdppl 4096 684 0 648 7 1 6 6 0 8 0 pvpl 32 158486 0 135418 197 2 195 195 0 265 7 pmappl 200 338 0 322 1 0 1 1 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 158 0 22 5 0 5 5 0 8 0