panic: pool_do_get: shmpl free list modified: page 0xfffffd8067028000; item addr 0xfffffd80670287e0; offset 0x40=0x8 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 116049 940 0 0 0 1 syz-executor *190177 940 0 0 0x4000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83365ec5) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83966e88,1,ffff800037c21aa8) at pool_do_get+0x5df pool_get(ffffffff83966e88,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a3d6a98,ffff800037c21d00,34,ffff800037c21c50) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a3d6a98,ffff800037c21d00,ffff800037c21c50) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff800037c21d00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800037c21d00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8da1f673f50, count: 7 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 *cpu0: pool_do_get: shmpl free list modified: page 0xfffffd8067028000; item addr 0xfffffd80670287e0; offset 0x40=0x8 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83365ec5) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83966e88,1,ffff800037c21aa8) at pool_do_get+0x5df pool_get(ffffffff83966e88,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a3d6a98,ffff800037c21d00,34,ffff800037c21c50) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a3d6a98,ffff800037c21d00,ffff800037c21c50) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff800037c21d00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800037c21d00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8da1f673f50, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800037c218d0 rbx 0xffffffff83811ddf cpu_info_full_primary+0x2ddf rdx 0 rcx 0xffff80002a3d6a98 rax 0xffffffff83810ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x13bed08d81789cd3 r11 0x514860c0791b2fb3 r12 0xffffffff83811be0 cpu_info_full_primary+0x2be0 r13 0 r14 0 r15 0x1 rip 0xffffffff811a29e5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff800037c218c0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=190177 pid=940 tcnt=3 stat=onproc flags process=0 proc=4000000 runpri=50, usrpri=50, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a3d6038,0xffffffff83958d80 process=0xffff80003c4689d0 user=0xffff800037c1c000, vmspace=0xfffffd800bb675d8 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 940 116049 66464 0 7 0 syz-executor 940 324344 66464 0 3 0x4000080 fsleep syz-executor * 940 190177 66464 0 7 0x4000000 syz-executor 20445 523426 92983 0 3 0x90 nanoslp syz-executor 20445 127822 92983 0 3 0x4000090 lockf syz-executor 20445 290862 92983 0 3 0x4000090 fsleep syz-executor 64414 279696 31255 0 3 0x80 nanoslp syz-executor 64414 488552 31255 0 3 0x4000080 kqread syz-executor 64414 141604 31255 0 3 0x4000080 fsleep syz-executor 96386 77393 38056 0 3 0x80 nanoslp syz-executor 96386 64966 38056 0 3 0x4000080 kqread syz-executor 96386 493545 38056 0 3 0x4000080 fsleep syz-executor 20975 221648 39314 0 3 0x82 wait syz-executor 54485 37845 0 0 3 0x14280 nfsidl nfsio 75584 189815 0 0 3 0x14280 nfsidl nfsio 94683 390095 0 0 3 0x14280 nfsidl nfsio 1031 146630 0 0 3 0x14280 nfsidl nfsio 64946 135363 0 0 3 0x14280 nfsidl nfsio 51496 5511 0 0 3 0x14280 nfsidl nfsio 87558 260273 0 0 3 0x14280 nfsidl nfsio 60958 442725 0 0 3 0x14280 nfsidl nfsio 66924 339839 0 0 3 0x14280 nfsidl nfsio 83932 226921 0 0 3 0x14280 nfsidl nfsio 96523 348463 0 0 3 0x14280 nfsidl nfsio 11681 367374 0 0 3 0x14280 nfsidl nfsio 45814 47219 0 0 3 0x14280 nfsidl nfsio 54522 66865 0 0 3 0x14280 nfsidl nfsio 98036 163272 0 0 3 0x14280 nfsidl nfsio 23299 368186 0 0 3 0x14280 nfsidl nfsio 70013 516175 0 0 3 0x14280 nfsidl nfsio 43678 290415 0 0 3 0x14280 nfsidl nfsio 62169 236046 0 0 3 0x14280 nfsidl nfsio 83204 450148 0 0 3 0x14280 nfsidl nfsio 16415 191999 1 0 3 0x100083 ttyin getty 84065 492667 39314 0 3 0x2 biowait syz-executor 46780 113159 0 0 3 0x14200 bored sosplice 38056 253087 39314 0 3 0x82 nanoslp syz-executor 92983 136991 39314 0 3 0x82 nanoslp syz-executor 31255 295243 39314 0 3 0x82 nanoslp syz-executor 27309 451337 39314 0 3 0x82 nanoslp syz-executor 66464 504279 39314 0 3 0x82 nanoslp syz-executor 31915 155600 39314 0 3 0x82 nanoslp syz-executor 39314 292268 9498 0 3 0x82 kqread syz-executor 9498 119304 6865 0 3 0x10008a sigsusp ksh 6865 27610 11400 0 3 0x98 kqread sshd-session 11400 390734 40075 0 3 0x92 kqread sshd-session 40075 203837 1 0 3 0x88 kqread sshd 28787 400753 51782 74 3 0x1100092 bpf pflogd 51782 11154 1 0 3 0x80 sbwait pflogd 75025 142864 24124 73 3 0x1100090 kqread syslogd 24124 236532 1 0 3 0x100082 sbwait syslogd 68240 258108 1 0 3 0x100080 kqread resolvd 61052 342417 7209 77 3 0x100092 kqread dhcpleased 57405 12479 7209 77 3 0x100092 kqread dhcpleased 7209 164263 1 0 3 0x80 kqread dhcpleased 52695 499595 0 0 3 0x14200 bored smr 40753 441994 0 0 3 0x14200 pgzero zerothread 39816 4133 0 0 3 0x14200 aiodoned aiodoned 61046 178442 0 0 3 0x14200 syncer update 50043 393777 0 0 3 0x14200 cleaner cleaner 30915 501222 0 0 3 0x14200 reaper reaper 83344 34911 0 0 3 0x14200 pgdaemon pagedaemon 24138 147717 0 0 3 0x14200 bored viomb 43863 507917 0 0 3 0x40014200 acpi0 acpi0 96436 361614 0 0 3 0x40014200 idle1 74430 215652 0 0 3 0x14200 bored softnet7 4696 289664 0 0 3 0x14200 bored softnet6 50080 450290 0 0 3 0x14200 bored softnet5 14099 185914 0 0 3 0x14200 bored softnet4 64025 401237 0 0 3 0x14200 bored softnet3 33071 118984 0 0 3 0x14200 bored softnet2 74782 192054 0 0 3 0x14200 bored softnet1 82366 366557 0 0 3 0x14200 bored softnet0 44246 488926 0 0 3 0x14200 smrbar systqmp 12778 71805 0 0 3 0x14200 bored systq 47112 74050 0 0 3 0x14200 tmoslp softclockmp 92998 342551 0 0 3 0x40014200 tmoslp softclock 12348 439015 0 0 3 0x40014200 idle0 1 394861 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex shmpl r = 0 (0xffffffff83966ea0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter_try+0x1ad sys/kern/kern_lock.c:311 #2 mtx_enter+0x62 sys/kern/kern_lock.c:261 #3 pool_get+0x124 sys/kern/subr_pool.c:581 #4 shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 #5 sys_shmget+0x195 sys/kern/sysv_shm.c:482 #6 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #6 syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 #7 Xsyscall+0x128 Process 940 (syz-executor) thread 0xffff80002a3d6a98 (190177) Process 84065 (syz-executor) thread 0xffff80003a039788 (492667) Process 44246 (systqmp) thread 0xffff8000ffffe298 (488926) ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10217 11052K 11305K 166960K 12212 0 pcb 19 14K 16K 166960K 367 0 rtable 198 10K 10K 166960K 433 0 pf 40 18K 82K 166960K 164 0 ifaddr 41 7K 8K 166960K 100 0 ifgroup 60 2K 2K 166960K 165 0 sysctl 3 1K 9K 166960K 15 0 counters 72 37K 37K 166960K 218 0 ioctlops 0 0K 4K 166960K 1817 0 iov 0 0K 24K 166960K 78 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1367 86K 87K 166960K 2159 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 17 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 69 0 dirhash 12 2K 2K 166960K 24 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 89K 166960K 1012 0 sigio 0 0K 0K 166960K 117 0 proc 72 115K 164K 166960K 699 0 subproc 72 4K 4K 166960K 90 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 1 0K 0K 166960K 144 0 in_multi 84 6K 7K 166960K 156 0 ether_multi 1 0K 0K 166960K 7 0 mrt 1 0K 0K 166960K 10 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 97 440K 440K 166960K 97 0 exec 0 0K 1K 166960K 533 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 258 153K 169K 166960K 10964 0 UVM aobj 26 3K 3K 166960K 32 0 pinsyscall 42 84K 100K 166960K 2171 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 63 0 NDP 13 0K 1K 166960K 68 0 temp 78 8652K 8720K 166960K 38690 0 kqueue 16 26K 32K 166960K 209 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 89 0 86 1 0 1 1 0 8 0 rtentry 176 146 0 69 5 0 5 5 0 8 0 unpcb 144 687 0 667 10 8 2 9 0 8 1 syncache 336 12 0 12 2 1 1 1 0 8 1 tcpqe 32 2 0 2 1 0 1 1 0 8 1 tcpcb 736 413 0 407 12 6 6 7 0 8 5 arp 128 17 0 8 1 0 1 1 0 8 0 inpcb 328 1281 0 1269 12 6 6 12 0 8 4 nd6 144 27 0 9 1 0 1 1 0 8 0 pkpcb 40 3 0 3 2 2 0 1 0 8 0 kcovpl 48 10 0 2 1 0 1 1 0 8 0 mppekey 1024 3 0 3 1 1 0 1 0 8 0 ppxss 1192 61 0 60 1 0 1 1 0 8 0 pppxif 1504 6 0 5 2 1 1 1 0 8 0 pffrag 232 3 0 0 1 0 1 1 0 482 0 pffrnode 88 3 0 0 1 0 1 1 0 8 0 pffrent 40 4 0 1 1 0 1 1 0 8 0 pfosfp 40 1429 0 1428 5 4 1 5 0 8 0 pfosfpen 112 1429 0 1428 21 11 10 21 0 8 9 pfrktable 1344 1 0 1 1 1 0 1 0 8 0 pfstitem 24 109 0 21 1 0 1 1 0 8 0 pfstkey 128 239 0 151 3 0 3 3 0 8 0 pfstate 384 173 0 86 9 0 9 9 0 8 0 pfrule 1344 46 0 41 2 1 1 2 0 8 0 rttmr 136 2 0 2 1 1 0 1 0 8 0 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 642 0 265 31 3 28 31 0 8 2 art_table 40 646 0 265 5 0 5 5 0 8 0 art_node 32 145 0 78 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 2 1 1 0 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 66 0 56 1 0 1 1 0 8 0 shmpl 112 29 0 6 1 0 1 1 0 8 0 pool(0xffffffff83966e88:shmpl): page inconsistency: page 0xfffffd8067028000; 11 on list, 23 missing, 35 items per page dirhash 1024 25 0 8 3 0 3 3 0 8 0 dino2pl 256 3283 0 1771 96 0 96 96 0 8 0 ffsino 296 3283 0 1771 118 0 118 118 0 8 0 nchpl 144 4648 0 2941 64 0 64 64 0 8 0 rtmask 32 18 0 18 2 1 1 1 0 8 1 uvmvnodes 80 3754 0 0 77 0 77 77 0 8 0 vnodes 216 3754 0 0 209 0 209 209 0 8 0 namei 1024 15578 0 15578 2 1 1 2 0 8 1 percpumem 16 124 0 73 1 0 1 1 0 8 0 kstatmem 264 98 0 70 4 1 3 3 0 8 1 scsiplug 72 10 0 10 1 1 0 1 0 8 0 scxspl 216 31367 0 31366 10 9 1 8 1 8 0 plimitpl 152 422 0 405 1 0 1 1 0 8 0 sigapl 424 1338 0 1264 9 0 9 9 0 8 0 knotepl 120 561 0 0 17 0 17 17 0 8 0 kqueuepl 224 605 0 587 11 6 5 7 0 8 3 pipepl 344 254 0 227 3 0 3 3 0 8 0 fdescpl 528 1294 0 1263 3 0 3 3 0 8 0 filepl 160 8282 0 8047 28 13 15 25 0 8 3 lockfpl 104 409 0 405 1 0 1 1 0 8 0 lockfspl 48 167 0 164 1 0 1 1 0 8 0 sessionpl 144 30 0 21 1 0 1 1 0 8 0 pgrppl 48 53 0 36 1 0 1 1 0 8 0 ucredpl 104 1391 0 1377 1 0 1 1 0 8 0 zombiepl 144 1267 0 1264 1 0 1 1 0 8 0 processpl 1232 1338 0 1264 7 0 7 7 0 8 0 procpl 664 2823 0 2741 8 0 8 8 0 8 0 sosppl 168 4 0 4 3 2 1 1 0 8 1 sockpl 752 2080 0 2045 30 20 10 24 0 8 6 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 3 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 127 0 0 16 0 16 16 0 8 0 mcl2k 2048 22 0 0 3 0 3 3 0 8 0 mtagpl 96 5 0 0 1 0 1 1 0 8 0 mbufpl 256 221 0 0 12 0 12 12 0 8 0 bufpl 280 14055 0 7912 439 0 439 439 0 8 0 anonpl 32 12675 0 0 103 0 103 103 0 246 0 amapchunkpl 152 36151 0 35559 34 5 29 29 0 158 5 amappl16 200 5646 0 5612 46 29 17 28 0 8 8 amappl15 192 9 0 9 2 2 0 1 0 8 0 amappl14 184 125 0 113 1 0 1 1 0 8 0 amappl13 176 6 0 6 1 1 0 1 0 8 0 amappl12 168 1970 0 1939 4 2 2 3 0 8 0 amappl11 160 49 0 35 1 0 1 1 0 8 0 amappl10 152 8 0 7 1 0 1 1 0 8 0 amappl9 144 251 0 250 2 1 1 1 0 8 0 amappl8 136 22 0 19 1 0 1 1 0 8 0 amappl7 128 118 0 105 1 0 1 1 0 8 0 amappl6 120 204 0 200 1 0 1 1 0 8 0 amappl5 112 137 0 127 1 0 1 1 0 8 0 amappl4 104 323 0 301 1 0 1 1 0 8 0 amappl3 96 7102 0 6981 4 0 4 4 0 8 0 amappl2 88 712 0 648 2 0 2 2 0 8 0 amappl1 80 13010 0 12406 16 1 15 15 0 8 1 amappl 88 10081 0 9896 5 0 5 5 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma512 512 1 0 1 1 1 0 1 0 8 0 dma256 256 8 0 8 3 3 0 1 0 8 0 dma128 128 259 0 259 2 2 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 72 31 0 6 1 0 1 1 0 8 0 uaddrrnd 24 1294 0 1263 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1294 0 1263 1 0 1 1 0 8 0 vmmpekpl 168 12485 0 12439 3 0 3 3 0 8 0 vmmpepl 168 89272 0 87243 114 8 106 111 0 357 6 vmsppl 488 1293 0 1263 6 1 5 5 0 8 0 rwobjpl 80 30182 0 25430 100 2 98 98 0 8 0 pdppl 4096 2596 0 2526 108 36 72 84 0 8 2 pvpl 32 21517 0 0 175 1 174 175 0 265 0 pmappl 256 1293 0 1263 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 302 0 53 8 0 8 8 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83365ec5) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83966e88,1,ffff800037c21aa8) at pool_do_get+0x5df pool_get(ffffffff83966e88,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a3d6a98,ffff800037c21d00,34,ffff800037c21c50) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a3d6a98,ffff800037c21d00,ffff800037c21c50) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff800037c21d00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800037c21d00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8da1f673f50, count: -8 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299edff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 end of kernel end trace frame: 0x71adfd6385b0, count: 12 ddb{1}> trace x86_ipi_db(ffff8000299edff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 end of kernel end trace frame: 0x71adfd6385b0, count: -3