panic: pool_do_get: shmpl free list modified: page 0xfffffd80601c2000; item addr 0xfffffd80601c25b0; offset 0x40=0x1a Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 277454 25117 0 0 0 1 syz-executor *108210 25117 0 0 0x4000000 0K syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4074) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8391b118,2,ffff80003bc087e8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8391b118,2) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c4274b0,ffff80003bc08a40,12,ffff80003bc08990) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c4274b0,ffff80003bc08a40,ffff80003bc08990) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80003bc08a40) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003bc08a40) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3b8d8f97060, 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 0xfffffd80601c2000; item addr 0xfffffd80601c25b0; offset 0x40=0x1a ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4074) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8391b118,2,ffff80003bc087e8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8391b118,2) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c4274b0,ffff80003bc08a40,12,ffff80003bc08990) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c4274b0,ffff80003bc08a40,ffff80003bc08990) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80003bc08a40) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003bc08a40) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3b8d8f97060, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80003bc08620 rbx 0xffffffff837e6dd7 cpu_info_full_primary+0x2dd7 rdx 0 rcx 0xffff80003c4274b0 rax 0xffffffff837e5ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x644be872c204e172 r11 0x75c472212406350d r12 0xffffffff837e6bd8 cpu_info_full_primary+0x2bd8 r13 0 r14 0 r15 0x1 rip 0xffffffff81c778d5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003bc08610 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=108210 pid=25117 tcnt=2 stat=onproc flags process=0 proc=4000000 runpri=50, usrpri=86, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c426f90,0xffffffff839b56f8 process=0xffff8000fffedd28 user=0xffff80003bc03000, vmspace=0xfffffd806c018020 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 25117 277454 57130 0 7 0 syz-executor *25117 108210 57130 0 7 0x4000000 syz-executor 82314 520012 37544 0 3 0x80 nanoslp syz-executor 82314 520168 37544 0 3 0x4000080 kqread syz-executor 82314 109671 37544 0 3 0x4000080 fsleep syz-executor 54566 236670 85187 0 3 0x80 nanoslp syz-executor 54566 154125 85187 0 3 0x4000080 ttyout syz-executor 54566 298345 85187 0 3 0x4000080 fsleep syz-executor 3135 121129 0 0 3 0x14200 acct acct 69375 289494 18891 0 3 0x82 wait syz-executor 23019 467641 0 0 3 0x14200 bored sosplice 82291 80704 91570 0 3 0x100082 sbwait arp 72453 30479 79475 0 3 0x100082 sbwait arp 79475 152223 75353 0 3 0x10008a sigsusp sh 91570 473683 15096 0 3 0x10008a sigsusp sh 37544 234381 18891 0 3 0x82 nanoslp syz-executor 75353 225956 18891 0 3 0x82 wait syz-executor 15096 481918 18891 0 3 0x82 wait syz-executor 57130 226141 18891 0 3 0x82 nanoslp syz-executor 79508 62822 18891 0 3 0x82 wait syz-executor 93247 119606 18891 0 3 0x82 nanoslp syz-executor 85187 283069 18891 0 3 0x82 nanoslp syz-executor 18891 439780 14511 0 3 0x82 kqread syz-executor 14511 123496 67046 0 3 0x10008a sigsusp ksh 67046 151666 55985 0 3 0x98 kqread sshd-session 55985 462837 41797 0 3 0x92 kqread sshd-session 66640 332529 1 0 3 0x100083 ttyopn getty 41797 419829 1 0 3 0x88 kqread sshd 14439 392597 62596 74 3 0x1100092 bpf pflogd 62596 303987 1 0 3 0x80 sbwait pflogd 80224 280273 30230 73 3 0x1100090 kqread syslogd 30230 357099 1 0 3 0x100082 sbwait syslogd 73150 436092 1 0 3 0x100080 kqread resolvd 61268 447628 64028 77 3 0x100092 kqread dhcpleased 93880 262077 64028 77 3 0x100092 kqread dhcpleased 64028 319507 1 0 3 0x80 kqread dhcpleased 43435 108578 0 0 3 0x14200 bored smr 73473 116402 0 0 3 0x14200 pgzero zerothread 31946 402738 0 0 3 0x14200 aiodoned aiodoned 22395 333435 0 0 3 0x14200 syncer update 55555 147396 0 0 3 0x14200 cleaner cleaner 68682 358446 0 0 3 0x14200 reaper reaper 91600 436965 0 0 3 0x14200 pgdaemon pagedaemon 71539 397927 0 0 3 0x14200 bored viomb 51956 262045 0 0 3 0x40014200 acpi0 acpi0 7302 242095 0 0 3 0x40014200 idle1 98069 82927 0 0 3 0x14200 bored softnet3 60930 450334 0 0 3 0x14200 bored softnet2 35122 364604 0 0 3 0x14200 bored softnet1 62718 316147 0 0 3 0x14200 bored softnet0 73670 219399 0 0 3 0x14200 bored systqmp 9613 178476 0 0 3 0x14200 bored systq 12353 268233 0 0 3 0x14200 tmoslp softclockmp 82040 64728 0 0 3 0x40014200 tmoslp softclock 26517 21028 0 0 3 0x40014200 idle0 1 214313 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 (0xffffffff8391b130) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 mtx_enter_try+0x1ad sys/kern/kern_lock.c:296 #2 mtx_enter+0x62 sys/kern/kern_lock.c:253 #3 pool_get+0x10b sys/kern/subr_pool.c:578 #4 shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 #5 sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 #6 syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] #6 syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 #7 Xsyscall+0x128 Process 25117 (syz-executor) thread 0xffff80003c4274b0 (108210) ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10240 11172K 11491K 166960K 12908 0 pcb 17 12K 12K 166960K 159 0 rtable 173 7K 8K 166960K 526 0 pf 32 17K 67485K 166960K 105 0 ifaddr 36 6K 7K 166960K 88 0 ifgroup 51 2K 2K 166960K 135 0 sysctl 3 1K 9K 166960K 11 0 counters 66 36K 37K 166960K 272 0 ioctlops 0 0K 4K 166960K 1765 0 iov 0 0K 24K 166960K 49 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1397 88K 88K 166960K 2373 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 8 0 VM map 2 1K 1K 166960K 2 0 sem 11 0K 0K 166960K 33 0 dirhash 12 2K 2K 166960K 42 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 20 73K 93K 166960K 973 0 sigio 0 0K 0K 166960K 9 0 proc 73 91K 115K 166960K 704 0 subproc 72 4K 4K 166960K 91 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 111 0 in_multi 58 4K 6K 166960K 135 0 ether_multi 1 0K 0K 166960K 8 0 mrt 1 0K 0K 166960K 6 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 265 1182K 1182K 166960K 265 0 exec 0 0K 1K 166960K 552 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 254 172K 185K 166960K 10561 0 UVM aobj 17 4K 4K 166960K 20 0 pinsyscall 47 94K 106K 166960K 2140 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 34 0 NDP 11 0K 1K 166960K 52 0 temp 66 8693K 8759K 166960K 39835 0 kqueue 15 24K 30K 166960K 175 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 120 174 0 168 1 0 1 1 0 8 0 rtentry 176 162 0 89 5 0 5 5 0 8 0 unpcb 144 826 0 807 9 3 6 6 0 8 5 syncache 336 6 0 6 3 2 1 1 0 8 1 tcpcb 808 273 0 268 5 4 1 4 0 8 0 arp 128 31 0 12 1 0 1 1 0 8 0 inpcb 384 955 0 945 11 6 5 8 0 8 3 nd6 144 25 0 12 1 0 1 1 0 8 0 pkpcb 40 11 0 11 1 0 1 1 0 8 1 kcovpl 48 10 0 2 1 0 1 1 0 8 0 ppxss 1192 89 0 89 2 1 1 1 0 8 1 pppxif 1504 72 0 72 2 1 1 1 0 8 1 pffrag 232 6 0 0 1 0 1 1 0 482 0 pffrnode 88 6 0 0 1 0 1 1 0 8 0 pffrent 40 10 0 4 1 0 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 63 0 14 1 0 1 1 0 8 0 pfstkey 128 63 0 14 2 0 2 2 0 8 0 pfstate 384 63 0 14 5 0 5 5 0 8 0 pfrule 1344 21 0 16 2 1 1 2 0 8 0 rttmr 136 2 0 2 1 1 0 1 0 8 0 art_heap8 4096 3 0 0 3 0 3 3 0 8 0 art_heap4 256 635 0 371 26 3 23 26 0 8 2 art_table 32 638 0 371 4 0 4 4 0 8 0 art_node 16 157 0 94 1 0 1 1 0 8 0 sysvmsgpl 40 18 0 12 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 29 0 20 1 0 1 1 0 8 0 shmpl 112 17 0 3 1 0 1 1 0 8 0 pool(0xffffffff8391b118:shmpl): page inconsistency: page 0xfffffd80601c2000; 20 on list, 14 missing, 35 items per page dirhash 1024 39 0 22 3 0 3 3 0 8 0 dino2pl 256 3335 0 1831 95 0 95 95 0 8 0 ffsino 288 3335 0 1831 109 0 109 109 0 8 0 nchpl 144 4719 0 3028 64 0 64 64 0 8 0 rtmask 32 4 0 4 2 1 1 1 0 8 1 uvmvnodes 80 3950 0 0 81 0 81 81 0 8 0 vnodes 216 3950 0 0 220 0 220 220 0 8 0 namei 1024 16966 0 16966 2 1 1 2 0 8 1 percpumem 16 151 0 103 1 0 1 1 0 8 0 kstatmem 264 72 0 48 4 1 3 3 0 8 1 scsiplug 72 2 0 2 1 1 0 1 0 8 0 scxspl 216 15174 0 15174 12 10 2 8 1 8 2 plimitpl 152 382 0 364 1 0 1 1 0 8 0 sigapl 424 1288 0 1234 8 1 7 7 0 8 0 knotepl 120 767 0 0 24 0 24 24 0 8 0 kqueuepl 224 286 0 275 2 1 1 2 0 8 0 pipepl 336 192 0 165 3 0 3 3 0 8 0 fdescpl 520 1264 0 1230 3 0 3 3 0 8 0 filepl 160 8590 0 8359 19 3 16 16 0 8 6 lockfpl 104 355 0 353 2 0 2 2 0 8 1 lockfspl 48 162 0 160 1 0 1 1 0 8 0 sessionpl 144 27 0 18 1 0 1 1 0 8 0 pgrppl 48 48 0 31 1 0 1 1 0 8 0 ucredpl 104 1846 0 1833 1 0 1 1 0 8 0 zombiepl 144 1237 0 1234 1 0 1 1 0 8 0 processpl 1240 1288 0 1234 5 0 5 5 0 8 0 procpl 656 2713 0 2654 7 1 6 6 0 8 0 srpgc 96 9 0 9 2 1 1 1 0 8 1 sosppl 168 5 0 5 2 1 1 1 0 8 1 sockpl 728 1987 0 1952 21 9 12 16 0 8 8 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 110 0 0 14 0 14 14 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 32 0 0 4 0 4 4 0 8 0 mtagpl 96 34 0 0 1 0 1 1 0 8 0 mbufpl 256 269 0 0 17 0 17 17 0 8 0 bufpl 280 4018 0 126 278 0 278 278 0 8 0 anonpl 32 7887 0 0 64 0 64 64 0 246 0 amapchunkpl 152 33522 0 33013 27 0 27 27 0 158 5 amappl16 200 3434 0 3402 28 17 11 15 0 8 8 amappl15 192 8 0 8 1 1 0 1 0 8 0 amappl14 184 126 0 112 1 0 1 1 0 8 0 amappl13 176 6 0 6 3 3 0 1 0 8 0 amappl12 168 1948 0 1912 4 1 3 3 0 8 0 amappl11 160 54 0 40 1 0 1 1 0 8 0 amappl10 152 36 0 36 1 1 0 1 0 8 0 amappl9 144 246 0 246 1 1 0 1 0 8 0 amappl8 136 71 0 67 1 0 1 1 0 8 0 amappl7 128 129 0 115 1 0 1 1 0 8 0 amappl6 120 198 0 192 1 0 1 1 0 8 0 amappl5 112 132 0 122 1 0 1 1 0 8 0 amappl4 104 340 0 317 1 0 1 1 0 8 0 amappl3 96 6849 0 6735 5 1 4 4 0 8 0 amappl2 88 753 0 685 2 0 2 2 0 8 0 amappl1 80 12434 0 11777 17 1 16 16 0 8 1 amappl 88 9686 0 9515 6 1 5 5 0 92 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 2 0 2 2 1 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 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 19 0 18 1 0 1 1 0 8 0 aobjpl 72 19 0 3 1 0 1 1 0 8 0 uaddrrnd 24 1264 0 1230 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1264 0 1230 1 0 1 1 0 8 0 vmmpekpl 168 11597 0 11556 3 0 3 3 0 8 0 vmmpepl 168 84772 0 82657 108 6 102 102 0 357 8 vmsppl 480 1263 0 1230 5 0 5 5 0 8 0 rwobjpl 72 27328 0 22337 92 0 92 92 0 8 0 pdppl 4096 2536 0 2460 102 24 78 86 0 8 2 pvpl 32 16363 0 0 132 0 132 132 0 265 0 pmappl 256 1263 0 1230 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 397 0 37 11 0 11 11 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(ffffffff833d4074) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8391b118,2,ffff80003bc087e8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8391b118,2) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c4274b0,ffff80003bc08a40,12,ffff80003bc08990) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c4274b0,ffff80003bc08a40,ffff80003bc08990) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80003bc08a40) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003bc08a40) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:579 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3b8d8f97060, count: -8 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299ddff0) 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: 0x755475bdd430, count: 12 ddb{1}> trace x86_ipi_db(ffff8000299ddff0) 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: 0x755475bdd430, count: -3