panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd80648b3100+16 0x0!=0x2db36120e11d8ec1 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 475775 92018 0 0 0 0 syz-executor.0 *384671 92018 0 0 0x4000000 1K syz-executor.0 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(ffffffff8266dda8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff8266dda8) 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(1,3) at m_get+0x4c sys/kern/uipc_mbuf.c:250 sockargs(ffff800021b834d0,200000c0,8,3) at sockargs+0x8d sys/kern/uipc_syscalls.c:1125 sys_connect(ffff800020ab1650,ffff800021b83558,ffff800021b835a0) at sys_connect+0x9c sys/kern/uipc_syscalls.c:367 syscall(ffff800021b83620) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800021b83620) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,0,fffffffffffffed2,0,3,1ede8ae2010) at Xsyscall+0x128 end of kernel end trace frame: 0x1f06e9376d0, count: 6 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 0xfffffd80648b3100+16 0x0!=0x2db36120e11d8ec1 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(ffffffff8266dda8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff8266dda8) 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(1,3) at m_get+0x4c sys/kern/uipc_mbuf.c:250 sockargs(ffff800021b834d0,200000c0,8,3) at sockargs+0x8d sys/kern/uipc_syscalls.c:1125 sys_connect(ffff800020ab1650,ffff800021b83558,ffff800021b835a0) at sys_connect+0x9c sys/kern/uipc_syscalls.c:367 syscall(ffff800021b83620) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800021b83620) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,0,fffffffffffffed2,0,3,1ede8ae2010) at Xsyscall+0x128 end of kernel end trace frame: 0x1f06e9376d0, count: -9 ddb{1}> show registers rdi 0xffffffff81e91477 db_enter+0x17 rsi 0x37ae __ALIGN_SIZE+0x27ae rbp 0xffff800021b83230 rbx 0xffff800021b832e0 rdx 0x37af __ALIGN_SIZE+0x27af rcx 0xffff800021966000 rax 0xffff800021966000 r8 0xffffffff813f1aef kprintf+0x16f r9 0x1 r10 0x25 r11 0x8f1d612644e5dbdf r12 0x3000000008 r13 0xffff800021b83240 r14 0x100 r15 0x1 rip 0xffffffff81e91478 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800021b83220 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=384671 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020ab0c70,0xffffffff82651bd8 process=0xffff800020adce00 user=0xffff800021b7e000, vmspace=0xfffffd807f00a000 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 92018 475775 73361 0 7 0 syz-executor.0 *92018 384671 73361 0 7 0x4000000 syz-executor.0 22496 487240 65070 0 3 0x2 biowait syz-executor.1 14368 369666 0 0 3 0x14200 acct acct 73361 507047 65070 0 3 0x82 nanosleep syz-executor.0 15657 305115 0 0 3 0x14200 bored sosplice 65070 460751 64225 0 3 0x82 thrsleep syz-fuzzer 65070 299932 64225 0 3 0x4000082 nanosleep syz-fuzzer 65070 317765 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 366745 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 56789 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 219194 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 396464 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 93166 64225 0 3 0x4000082 nanosleep syz-fuzzer 65070 183655 64225 0 3 0x4000082 thrsleep syz-fuzzer 65070 10465 64225 0 3 0x4000082 kqread syz-fuzzer 64225 169374 35234 0 3 0x10008a pause ksh 35234 458260 39535 0 3 0x92 select sshd 3982 513645 1 0 3 0x100083 ttyin getty 39535 369270 1 0 3 0x80 select sshd 44388 94872 78301 74 3 0x100092 bpf pflogd 78301 83099 1 0 3 0x80 netio pflogd 20210 77055 36583 73 3 0x100090 kqread syslogd 36583 328538 1 0 3 0x100082 netio syslogd 48151 380864 1 77 3 0x100090 poll dhclient 61816 316788 1 0 3 0x80 poll dhclient 27812 180955 0 0 3 0x14200 pgzero zerothread 70208 409745 0 0 3 0x14200 aiodoned aiodoned 92110 118359 0 0 3 0x14200 syncer update 68939 82294 0 0 3 0x14200 cleaner cleaner 87697 354291 0 0 3 0x14200 reaper reaper 78429 426742 0 0 3 0x14200 pgdaemon pagedaemon 23164 424668 0 0 3 0x14200 bored crynlk 63830 268912 0 0 3 0x14200 bored crypto 56858 69790 0 0 3 0x40014200 acpi0 acpi0 71396 349042 0 0 3 0x40014200 idle1 33612 442967 0 0 3 0x14200 bored softnet 16429 3048 0 0 3 0x14200 bored systqmp 13826 78427 0 0 3 0x14200 bored systq 40169 514230 0 0 3 0x40014200 bored softclock 93437 114767 0 0 3 0x40014200 idle0 63839 206419 0 0 3 0x14200 bored smr 1 323903 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 92018 (syz-executor.0) thread 0xffff800020ab1650 (384671) exclusive rwlock netlock r = 0 (0xffffffff824d2408) #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 (0xffffffff8264b430) #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 Process 22496 (syz-executor.1) thread 0xffff800020ab0508 (487240) exclusive rrwlock inode r = 0 (0xfffffd80725ca1b0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:562 #5 vget+0x1c3 sys/kern/vfs_subr.c:672 #6 ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1323 #8 ufs_lookup+0x14b4 sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:91 #10 vfs_lookup+0x7a6 sys/kern/vfs_lookup.c:568 #11 namei+0x63c sys/kern/vfs_lookup.c:249 #12 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785 #13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806fa41c50) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:562 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #9 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9604 6462K 8218K 78643K 36810 0 0 pcb 14 10K 12K 78643K 2466 0 0 rtable 99 13K 14K 78643K 7202 0 0 ifaddr 86 19K 20K 78643K 867 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1783 0 0 iov 0 0K 28K 78643K 8411 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1227 77K 77K 78643K 12453 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 9K 78643K 164 0 0 VM map 2 1K 1K 78643K 8 0 0 sem 12 0K 1K 78643K 1784 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 12363 0 0 sigio 0 0K 0K 78643K 138 0 0 proc 60 63K 95K 78643K 1959 0 0 subproc 32 2K 2K 78643K 291 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 608 0 0 in_multi 20 1K 2K 78643K 524 0 0 ether_multi 1 0K 0K 78643K 45 0 0 mrt 0 0K 0K 78643K 40 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 132 583K 583K 78643K 132 0 0 exec 0 0K 1K 78643K 2010 0 0 pfkey data 0 0K 4K 78643K 12 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 150 24K 32K 78643K 35789 0 0 UVM aobj 130 4K 4K 78643K 165 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 1251 0 0 NDP 21 0K 0K 78643K 257 0 0 temp 235 3557K 4196K 78643K 67682 0 0 kqueue 0 0K 0K 78643K 21 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 64 540 0 536 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 356 0 354 1 0 1 1 0 8 0 rtentry 112 1733 0 1703 2 0 2 2 0 8 0 unpcb 120 4528 0 4490 3 1 2 2 0 8 0 syncache 264 17 0 17 7 7 0 1 0 8 0 tcpqe 32 350 0 350 20 20 0 1 0 8 0 tcpcb 544 2854 0 2850 26 25 1 15 0 8 0 inpcb 280 9968 0 9960 24 22 2 9 0 8 1 rttmr 72 2 0 2 2 2 0 1 0 8 0 ip6q 72 4 0 4 2 2 0 1 0 8 0 ip6af 40 6 0 6 2 2 0 1 0 8 0 nd6 48 40 0 39 3 2 1 1 0 8 0 pkpcb 40 45 0 45 10 10 0 1 0 8 0 swfcl 56 10 0 0 1 0 1 1 0 8 0 ppxss 1128 125 0 125 25 25 0 1 0 8 0 pffrag 232 31 0 31 9 9 0 1 0 482 0 pffrnode 88 31 0 31 9 9 0 1 0 8 0 pffrent 40 69 0 69 9 9 0 1 0 8 0 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 24 255 0 243 1 0 1 1 0 8 0 pfstkey 112 255 0 243 2 1 1 2 0 8 0 pfstate 328 255 0 243 7 5 2 5 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 190 0 189 4 3 1 3 0 8 0 art_heap4 256 5071 0 4913 23 11 12 15 0 8 0 art_table 32 5261 0 5102 2 0 2 2 0 8 0 art_node 16 1716 0 1688 1 0 1 1 0 8 0 sysvmsgpl 40 134 0 134 1 1 0 1 0 8 0 semapl 112 1782 0 1772 1 0 1 1 0 8 0 shmpl 112 163 0 35 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 20734 0 19326 46 0 46 46 0 8 0 ffsino 272 20734 0 19326 95 0 95 95 0 8 0 nchpl 144 39458 0 38989 61 41 20 61 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 208 5926 0 0 312 0 312 312 0 8 0 namei 1024 121910 0 121910 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vmpool 552 6 0 6 3 3 0 1 0 8 0 scsiplug 64 14 0 14 6 6 0 1 0 8 0 scxspl 192 118635 0 118634 39 38 1 7 0 8 0 plimitpl 152 895 0 887 1 0 1 1 0 8 0 sigapl 432 12518 0 12503 3 1 2 3 0 8 0 futexpl 56 195901 0 195901 1 0 1 1 0 8 1 knotepl 112 1516 0 1497 3 2 1 2 0 8 0 kqueuepl 104 2160 0 2158 7 6 1 4 0 8 0 pipepl 112 13072 0 13053 20 18 2 3 0 8 1 fdescpl 488 12519 0 12503 3 0 3 3 0 8 0 filepl 152 85241 0 85140 62 56 6 14 0 8 2 lockfpl 104 3485 0 3484 1 0 1 1 0 8 0 lockfspl 48 1294 0 1293 1 0 1 1 0 8 0 sessionpl 112 33 0 22 1 0 1 1 0 8 0 pgrppl 48 103 0 92 1 0 1 1 0 8 0 ucredpl 96 14717 0 14708 1 0 1 1 0 8 0 zombiepl 144 12504 0 12504 2 1 1 1 0 8 1 processpl 896 12537 0 12504 4 0 4 4 0 8 0 procpl 632 34098 0 34055 17 12 5 5 0 8 1 srpgc 64 24 0 24 10 10 0 1 0 8 0 sosppl 128 103 0 103 14 14 0 1 0 8 0 sockpl 384 14997 0 14949 48 42 6 16 0 8 0 mcl64k 65536 32 0 0 3 0 3 3 0 8 0 mcl16k 16384 9 0 0 2 0 2 2 0 8 0 mcl12k 12288 33 0 0 2 0 2 2 0 8 0 mcl9k 9216 18 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 33 0 0 3 0 3 3 0 8 0 mcl2k2 2112 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 369 0 0 12 1 11 12 0 8 0 mtagpl 80 619 0 0 11 0 11 11 0 8 0 mbufpl 256 1490 0 0 72 0 72 72 0 8 0 bufpl 256 45657 0 38609 441 0 441 441 0 8 0 anonpl 16 904387 0 896647 136 104 32 47 0 124 0 amapchunkpl 152 60482 0 60395 50 45 5 12 0 158 0 amappl16 192 55695 0 55304 101 81 20 32 0 8 0 amappl15 184 5719 0 5719 2 2 0 1 0 8 0 amappl14 176 818 0 813 2 1 1 1 0 8 0 amappl13 168 1242 0 1242 3 3 0 1 0 8 0 amappl12 160 4443 0 4442 2 1 1 1 0 8 0 amappl11 152 630 0 615 1 0 1 1 0 8 0 amappl10 144 162 0 158 1 0 1 1 0 8 0 amappl9 136 2075 0 2066 1 0 1 1 0 8 0 amappl8 128 1735 0 1665 4 1 3 3 0 8 0 amappl7 120 261 0 253 1 0 1 1 0 8 0 amappl6 112 625 0 609 1 0 1 1 0 8 0 amappl5 104 5018 0 5005 1 0 1 1 0 8 0 amappl4 96 8494 0 8458 1 0 1 1 0 8 0 amappl3 88 5607 0 5600 1 0 1 1 0 8 0 amappl2 80 103503 0 103424 4 2 2 3 0 8 0 amappl1 72 246949 0 246516 26 16 10 20 0 8 0 amappl 80 34551 0 34515 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 64 164 0 35 3 0 3 3 0 8 0 uaddrrnd 24 12525 0 12503 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 12525 0 12503 1 0 1 1 0 8 0 vmmpekpl 168 100118 0 100084 3 0 3 3 0 8 0 vmmpepl 168 1463524 0 1461952 198 122 76 84 0 357 0 vmsppl 368 12518 0 12503 2 0 2 2 0 8 0 pdppl 4096 25057 0 25018 6 0 6 6 0 8 1 pvpl 32 3079633 0 3068563 411 314 97 126 0 265 7 pmappl 232 12524 0 12509 4 3 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 701 0 44 19 0 19 19 0 8 0