panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd8063509100+16 0x4285000000000000!=0x4285dfe09c283018 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 242141 38259 0 0 0 0 syz-executor.0 *328626 86696 0 0 0 1K dhclient 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(ffffffff826605d8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff826605d8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get() at pool_get+0x91 sys/kern/subr_pool.c:572 m_get(2,3) at m_get+0x4c sys/kern/uipc_mbuf.c:250 sbappendaddr(fffffd806f6c7180,fffffd806f6c7208,ffffffff823d9e10,fffffd8065745b00,0) at sbappendaddr+0x140 sys/kern/uipc_socket2.c:802 rtm_sendup(fffffd806f6c7180,fffffd8065745b00,0) at rtm_sendup+0xe7 sys/net/rtsock.c:594 route_input(fffffd8065745b00,fffffd806f6c7180,2) at route_input+0x489 sys/net/rtsock.c:572 route_output(fffffd8065745b00,fffffd806f6c7180,0,0) at route_output+0x80c sys/net/rtsock.c:857 route_usrreq(fffffd806f6c7180,9,fffffd8065745b00,0,0,ffff800020a5f3c8) at route_usrreq+0x363 sys/net/rtsock.c:275 sosend(fffffd806f6c7180,0,ffff800020aa4f10,0,0,0) at sosend+0x645 sys/kern/uipc_socket.c:524 dofilewritev(ffff800020a5f3c8,6,ffff800020aa4f10,0,ffff800020aa5000) at dofilewritev+0x1b7 sys/kern/sys_generic.c:364 sys_writev(ffff800020a5f3c8,ffff800020aa4fb0,ffff800020aa5000) at sys_writev+0xa7 sys/kern/sys_generic.c:311 syscall(ffff800020aa5080) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020aa5080) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 end trace frame: 0xffff800020aa5100, 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{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 0xfffffd8063509100+16 0x4285000000000000!=0x4285dfe09c283018 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(ffffffff826605d8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff826605d8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get() at pool_get+0x91 sys/kern/subr_pool.c:572 m_get(2,3) at m_get+0x4c sys/kern/uipc_mbuf.c:250 sbappendaddr(fffffd806f6c7180,fffffd806f6c7208,ffffffff823d9e10,fffffd8065745b00,0) at sbappendaddr+0x140 sys/kern/uipc_socket2.c:802 rtm_sendup(fffffd806f6c7180,fffffd8065745b00,0) at rtm_sendup+0xe7 sys/net/rtsock.c:594 route_input(fffffd8065745b00,fffffd806f6c7180,2) at route_input+0x489 sys/net/rtsock.c:572 route_output(fffffd8065745b00,fffffd806f6c7180,0,0) at route_output+0x80c sys/net/rtsock.c:857 route_usrreq(fffffd806f6c7180,9,fffffd8065745b00,0,0,ffff800020a5f3c8) at route_usrreq+0x363 sys/net/rtsock.c:275 sosend(fffffd806f6c7180,0,ffff800020aa4f10,0,0,0) at sosend+0x645 sys/kern/uipc_socket.c:524 dofilewritev(ffff800020a5f3c8,6,ffff800020aa4f10,0,ffff800020aa5000) at dofilewritev+0x1b7 sys/kern/sys_generic.c:364 sys_writev(ffff800020a5f3c8,ffff800020aa4fb0,ffff800020aa5000) at sys_writev+0xa7 sys/kern/sys_generic.c:311 syscall(ffff800020aa5080) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020aa5080) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,79,0,79,ad8459c6,c91ee04f000) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffdb190, count: -15 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020aa47a0 rbx 0xffff800020aa4850 rdx 0xffff800020a5f3c8 rcx 0 rax 0 r8 0xffffffff81844b3f kprintf+0x16f r9 0x1 r10 0x25 r11 0xbab14dd8a625d0bd r12 0x3000000008 r13 0xffff800020aa47b0 r14 0x100 r15 0x1 rip 0xffffffff81a1eac8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020aa4790 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (dhclient) pid=328626 stat=onproc flags process=0 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a5e280,0xffff800020a5f650 process=0xffff800020a8a390 user=0xffff800020aa0000, vmspace=0xfffffd807f00b5c0 estcpu=0, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 89655 366641 7528 0 2 0 syz-executor.1 38259 242141 72947 0 7 0 syz-executor.0 38259 157926 72947 0 2 0x4000000 syz-executor.0 72947 68413 18666 0 3 0x82 nanosleep syz-executor.0 8855 455188 0 0 3 0x14200 acct acct 7528 369851 18666 0 3 0x82 nanosleep syz-executor.1 74858 512942 0 0 3 0x14200 bored sosplice 18666 148943 59038 0 3 0x82 nanosleep syz-fuzzer 18666 79531 59038 0 3 0x4000082 nanosleep syz-fuzzer 18666 133749 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 240756 59038 0 3 0x4000082 kqread syz-fuzzer 18666 74462 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 222370 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 254820 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 426025 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 447741 59038 0 3 0x4000082 thrsleep syz-fuzzer 18666 29062 59038 0 3 0x4000082 thrsleep syz-fuzzer 59038 29780 9597 0 3 0x10008a pause ksh 9597 54159 52184 0 3 0x92 select sshd 54690 430251 1 0 3 0x100083 ttyopn getty 52184 50245 1 0 3 0x80 select sshd 94503 439777 72317 74 3 0x100092 bpf pflogd 72317 233379 1 0 3 0x80 netio pflogd 2441 430244 1621 73 3 0x100090 kqread syslogd 1621 404298 1 0 3 0x100082 netio syslogd 35689 463187 1 77 3 0x100090 poll dhclient *86696 328626 1 0 7 0 dhclient 47994 462212 0 0 3 0x14200 pgzero zerothread 13479 59020 0 0 3 0x14200 aiodoned aiodoned 21467 174533 0 0 3 0x14200 syncer update 28653 397992 0 0 3 0x14200 cleaner cleaner 82910 54272 0 0 3 0x14200 reaper reaper 34347 94174 0 0 3 0x14200 pgdaemon pagedaemon 2703 479942 0 0 3 0x14200 bored crynlk 34600 501498 0 0 3 0x14200 bored crypto 18377 385571 0 0 3 0x40014200 acpi0 acpi0 26509 299934 0 0 3 0x40014200 idle1 639 394729 0 0 3 0x14200 bored softnet 98318 426288 0 0 3 0x14200 bored systqmp 15040 87991 0 0 3 0x14200 bored systq 94135 248763 0 0 3 0x40014200 bored softclock 41937 222731 0 0 3 0x40014200 idle0 79609 357374 0 0 3 0x14200 bored smr 1 401173 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 86696 (dhclient) thread 0xffff800020a5f3c8 (328626) exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8266ff88) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 solock+0x66 sys/kern/uipc_socket2.c:292 #2 sosend+0x51b sys/kern/uipc_socket.c:512 #3 dofilewritev+0x1b7 sys/kern/sys_generic.c:364 #4 sys_writev+0xa7 sys/kern/sys_generic.c:311 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #6 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9556 7196K 8876K 78643K 14630 0 0 pcb 13 8K 8K 78643K 249 0 0 rtable 101 4K 5K 78643K 790 0 0 ifaddr 70 15K 15K 78643K 251 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1483 0 0 iov 0 0K 16K 78643K 109 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1233 77K 78K 78643K 2395 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 7 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 282 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 25K 78643K 695 0 0 sigio 1 0K 0K 78643K 12 0 0 proc 60 63K 95K 78643K 689 0 0 subproc 32 2K 2K 78643K 119 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 50 0 0 in_multi 33 2K 2K 78643K 124 0 0 ether_multi 1 0K 0K 78643K 6 0 0 mrt 0 0K 0K 78643K 4 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 60 265K 265K 78643K 60 0 0 exec 0 0K 1K 78643K 308 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 96 21K 22K 78643K 3343 0 0 UVM aobj 130 6K 6K 78643K 133 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 201 0 0 NDP 15 0K 0K 78643K 75 0 0 temp 193 3556K 4195K 78643K 9305 0 0 kqueue 0 0K 0K 78643K 10 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 24 0 19 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 71 0 69 1 0 1 1 0 8 0 rtentry 112 126 0 87 2 0 2 2 0 8 0 unpcb 120 261 0 249 1 0 1 1 0 8 0 syncache 264 5 0 5 2 2 0 1 0 8 0 tcpqe 32 6623 0 6623 1 1 0 1 0 8 0 tcpcb 544 221 0 217 1 0 1 1 0 8 0 inpcb 280 758 0 751 3 1 2 2 0 8 1 rttmr 72 2 0 2 2 2 0 1 0 8 0 nd6 48 17 0 13 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 1 0 1 0 8 0 ppxss 1128 37 0 36 2 1 1 1 0 8 0 pffrag 232 9 0 9 3 2 1 1 0 482 1 pffrnode 88 9 0 9 3 2 1 1 0 8 1 pffrent 40 62 0 62 3 2 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 55 0 23 1 0 1 1 0 8 0 pfstkey 112 55 0 23 2 0 2 2 0 8 0 pfstate 328 55 0 23 4 0 4 4 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 256 523 0 307 18 4 14 15 0 8 0 art_table 32 524 0 307 2 0 2 2 0 8 0 art_node 16 125 0 90 1 0 1 1 0 8 0 sysvmsgpl 40 22 0 10 1 0 1 1 0 8 0 semupl 112 5 0 5 1 1 0 1 0 8 0 semapl 112 278 0 268 1 0 1 1 0 8 0 shmpl 112 131 0 3 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2519 0 1117 46 0 46 46 0 8 0 ffsino 272 2519 0 1117 94 0 94 94 0 8 0 nchpl 144 3637 0 2026 61 0 61 61 0 8 0 uvmvnodes 72 3518 0 0 64 0 64 64 0 8 0 vnodes 208 3518 0 0 186 0 186 186 0 8 0 namei 1024 12070 0 12070 3 2 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 10442 0 10442 17 14 3 7 0 8 3 plimitpl 152 71 0 63 1 0 1 1 0 8 0 sigapl 432 880 0 864 3 1 2 3 0 8 0 futexpl 56 15189 0 15189 1 0 1 1 0 8 1 knotepl 112 265 0 246 1 0 1 1 0 8 0 kqueuepl 104 210 0 208 1 0 1 1 0 8 0 pipepl 112 514 0 495 2 1 1 1 0 8 0 fdescpl 488 881 0 864 3 0 3 3 0 8 0 filepl 152 6605 0 6504 8 2 6 6 0 8 2 lockfpl 104 370 0 369 1 0 1 1 0 8 0 lockfspl 48 126 0 125 1 0 1 1 0 8 0 sessionpl 112 23 0 12 1 0 1 1 0 8 0 pgrppl 48 31 0 20 1 0 1 1 0 8 0 ucredpl 96 990 0 980 1 0 1 1 0 8 0 zombiepl 144 864 0 864 3 2 1 1 0 8 1 processpl 896 898 0 864 4 0 4 4 0 8 0 procpl 632 2356 0 2312 5 0 5 5 0 8 1 srpgc 64 8 0 8 3 3 0 1 0 8 0 sosppl 128 2 0 2 1 1 0 1 0 8 0 sockpl 384 1100 0 1079 6 2 4 4 0 8 0 mcl64k 65536 12 0 0 2 0 2 2 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 6 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 14 0 0 2 0 2 2 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 190 0 0 22 0 22 22 0 8 0 mtagpl 80 237 0 0 5 0 5 5 0 8 0 mbufpl 256 592 0 0 33 0 33 33 0 8 0 bufpl 256 7848 0 1314 409 0 409 409 0 8 0 anonpl 16 109284 0 92286 83 14 69 79 0 124 0 amapchunkpl 152 5541 0 5430 8 2 6 7 0 158 0 amappl16 192 4461 0 3505 75 26 49 60 0 8 0 amappl15 184 152 0 148 2 1 1 1 0 8 0 amappl14 176 295 0 292 2 1 1 1 0 8 0 amappl13 168 8 0 7 1 0 1 1 0 8 0 amappl12 160 111 0 111 2 2 0 1 0 8 0 amappl11 152 73 0 57 1 0 1 1 0 8 0 amappl10 144 38 0 33 1 0 1 1 0 8 0 amappl9 136 834 0 827 1 0 1 1 0 8 0 amappl8 128 364 0 342 1 0 1 1 0 8 0 amappl7 120 81 0 74 1 0 1 1 0 8 0 amappl6 112 95 0 81 1 0 1 1 0 8 0 amappl5 104 277 0 263 1 0 1 1 0 8 0 amappl4 96 961 0 930 1 0 1 1 0 8 0 amappl3 88 445 0 440 1 0 1 1 0 8 0 amappl2 80 5858 0 5785 4 2 2 3 0 8 0 amappl1 72 29985 0 29548 26 16 10 20 0 8 0 amappl 80 2689 0 2650 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 17 0 17 1 1 0 1 0 8 0 aobjpl 64 132 0 3 3 0 3 3 0 8 0 uaddrrnd 24 881 0 864 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 881 0 864 1 0 1 1 0 8 0 vmmpekpl 168 11188 0 11155 2 0 2 2 0 8 0 vmmpepl 168 117642 0 115483 173 48 125 128 0 357 29 vmsppl 368 880 0 864 2 0 2 2 0 8 0 pdppl 4096 1769 0 1728 7 1 6 6 0 8 0 pvpl 32 319247 0 299048 209 40 169 185 0 265 4 pmappl 232 880 0 864 2 1 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 603 0 10 17 0 17 17 0 8 0