panic: pool_do_get: shmpl free list modified: page 0xfffff4006cfa2000; item addr 0xfffff4006cfa2c40; offset 0x40=0x6a302b06 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *495624 47345 0 0 0x4000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8347e1d1) at panic+0x1cf sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ad10c0,1,ffff80002f0ab3d8) at pool_do_get+0x5bc pool_get(ffffffff83ad10c0,1) at pool_get+0x11a sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c8fa7e8,ffff80002f0ab620,40,ffff80002f0ab570) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c8fa7e8,ffff80002f0ab620,ffff80002f0ab570) at sys_shmget+0x195 sys/kern/sysv_shm.c:501 syscall(ffff80002f0ab620) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002f0ab620) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6cb9d43b450, 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: pool_do_get: shmpl free list modified: page 0xfffff4006cfa2000; item addr 0xfffff4006cfa2c40; offset 0x40=0x6a302b06 ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8347e1d1) at panic+0x1cf sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ad10c0,1,ffff80002f0ab3d8) at pool_do_get+0x5bc pool_get(ffffffff83ad10c0,1) at pool_get+0x11a sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c8fa7e8,ffff80002f0ab620,40,ffff80002f0ab570) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c8fa7e8,ffff80002f0ab620,ffff80002f0ab570) at sys_shmget+0x195 sys/kern/sysv_shm.c:501 syscall(ffff80002f0ab620) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002f0ab620) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6cb9d43b450, count: -8 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002f0ab240 rbx 0xfffff4006cfa2c40 rdx 0 rcx 0 rax 0xffff80003c8fa7e8 r8 0x101010101010101 r9 0x8080808080808080 r10 0x946dcccf11ffb1f6 r11 0xac3052553934efcf r12 0 r13 0xffffffff83ad10c0 shm_pool r14 0 r15 0x1 rip 0xffffffff81f8aff5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002f0ab230 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (syz-executor) tid=495624 pid=47345 tcnt=3 stat=onproc flags process=0 proc=4000000 runpri=32, usrpri=74, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c8fbca8,0xffff80003c8fb258 process=0xffff8000ffffa898 user=0xffff80002f0a6000, vmspace=0xfffff40066d48e78 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 85481 441306 24244 0 2 0 syz-executor 85481 194167 24244 0 3 0x4000080 ttyin syz-executor 85481 441093 24244 0 3 0x4000080 fsleep syz-executor 85481 193896 24244 0 3 0x4000080 fsleep syz-executor 4883 463495 11437 0 2 0 syz-executor 4883 232385 11437 0 3 0x4000080 fsleep syz-executor 5831 255733 82498 0 2 0 syz-executor 5831 35250 82498 0 3 0x4000080 fsleep syz-executor 83724 247584 56590 0 2 0 syz-executor 83724 131425 56590 0 3 0x4000080 fsleep syz-executor 47345 11681 75082 0 2 0 syz-executor *47345 495624 75082 0 7 0x4000000 syz-executor 47345 16685 75082 0 2 0x4000000 syz-executor 4733 402064 73975 0 2 0xc80 syz-executor 4733 334094 73975 0 3 0x4000080 kqsel syz-executor 4733 101841 73975 0 3 0x4000080 fsleep syz-executor 59111 255052 1 0 3 0x100083 ttyin getty 33315 416581 12367 0 2 0x2 syz-executor 56590 487662 12367 0 2 0xc82 syz-executor 82498 248871 12367 0 2 0xc82 syz-executor 75082 114556 12367 0 2 0xc82 syz-executor 19278 12325 12367 0 2 0x2 syz-executor 73975 257711 12367 0 2 0xc82 syz-executor 24244 382247 12367 0 2 0xc82 syz-executor 11437 75702 12367 0 2 0xc82 syz-executor 12367 352764 1 0 3 0x82 kqread syz-executor 20161 435357 39330 0 3 0x98 kqread sshd-session 39330 196840 1 0 3 0x92 kqread sshd-session 42346 100409 1 73 3 0x1100090 kqread syslogd 25723 289125 0 0 3 0x14200 bored smr 49206 266294 0 0 2 0x14200 zerothread 63911 337922 0 0 3 0x14200 aiodoned aiodoned 93002 414297 0 0 3 0x14200 syncer update 15841 483241 0 0 3 0x14200 cleaner cleaner 98792 446386 0 0 3 0x14200 reaper reaper 71505 174619 0 0 3 0x14200 pgdaemon pagedaemon 34211 171892 0 0 3 0x14200 bored viomb 42503 123687 0 0 3 0x40014200 acpi0 acpi0 27549 280088 0 0 3 0x14200 bored softnet0 89030 388467 0 0 3 0x14200 bored systqmp 63209 417484 0 0 3 0x14200 bored systq 47455 145557 0 0 3 0x40014200 tmoslp softclock 31717 82775 0 0 3 0x40014200 idle0 1 91662 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 11032 12110K 13163K 166960K 12557 0 pcb 17 12K 12K 166960K 54 0 rtable 260 9K 9K 166960K 442 0 pf 37 14K 72K 166960K 92 0 ifaddr 43 7K 8K 166960K 59 0 ifgroup 55 2K 2K 166960K 78 0 sysctl 3 1K 9K 166960K 7 0 counters 34 17K 18K 166960K 46 0 ioctlops 0 0K 4K 166960K 77 0 iov 0 0K 16K 166960K 10 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1360 86K 86K 166960K 1603 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 6 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 19 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 97K 166960K 332 0 sigio 0 0K 0K 166960K 2 0 proc 20 25K 124K 166960K 528 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 28 0 in_multi 99 7K 7K 166960K 114 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 18 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 73 334K 334K 166960K 73 0 exec 0 0K 1K 166960K 382 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 156 91K 152K 166960K 4756 0 UVM aobj 5 2K 2K 166960K 7 0 pinsyscall 24 48K 96K 166960K 1436 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 6 0 NDP 12 0K 2K 166960K 36 0 temp 45 9112K 9135K 166960K 8749 0 kqueue 6 10K 24K 166960K 62 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 57 0 57 1 0 1 1 0 8 1 rtentry 136 134 0 21 4 0 4 4 0 8 0 unpcb 144 152 0 144 1 0 1 1 0 8 0 syncache 336 4 0 4 1 1 0 1 0 8 0 tcpcb 736 61 0 58 1 0 1 1 0 8 0 arp 96 21 0 4 1 0 1 1 0 8 0 ipq 40 3 0 1 1 0 1 1 0 8 0 ipqe 40 4 0 2 1 0 1 1 0 8 0 inpcb 328 208 0 203 3 1 2 2 0 8 0 ip6q 72 3 0 3 1 0 1 1 0 8 1 ip6af 40 6 0 6 1 0 1 1 0 8 1 nd6 112 30 0 4 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 0 1 1 0 8 1 ppxss 1072 9 0 9 1 0 1 1 0 8 1 pppxif 1416 2 0 2 1 0 1 1 0 8 1 pfstscr 40 10 0 8 1 0 1 1 0 8 0 pfanchor 1288 2 0 0 1 0 1 1 0 8 0 pfstitem 24 4 0 0 1 0 1 1 0 8 0 pfstkey 128 12 0 8 1 0 1 1 0 8 0 pfstate 384 6 0 4 1 0 1 1 0 8 0 pfrule 1360 4 0 4 1 0 1 1 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 550 0 62 31 0 31 31 0 8 0 art_table 40 552 0 62 5 0 5 5 0 8 0 art_node 32 134 0 33 1 0 1 1 0 8 0 sysvmsgpl 40 28 0 27 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 72 15 0 5 1 0 1 1 0 8 0 shmpl 112 4 0 2 1 0 1 1 0 8 0 pool(0xffffffff83ad10c0:shmpl): page inconsistency: page 0xfffff4006cfa2000; 32 on list, 2 missing, 35 items per page dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 1944 0 484 92 0 92 92 0 8 0 ffsino 256 1944 0 484 92 0 92 92 0 8 0 nchpl 144 2397 0 697 64 0 64 64 0 8 0 rtmask 32 2 0 2 1 0 1 1 0 8 1 vnodes 216 2190 0 0 122 0 122 122 0 8 0 namei 1024 7369 0 7368 3 2 1 2 0 8 0 kstatmem 264 39 0 14 2 0 2 2 0 8 0 scsiplug 72 1 0 1 1 0 1 1 0 8 1 scxspl 216 7983 0 7983 11 3 8 8 1 8 8 plimitpl 152 58 0 44 1 0 1 1 0 8 0 sigapl 424 628 0 594 6 0 6 6 0 8 1 knotepl 120 10864 0 10835 9 0 9 9 0 8 7 kqueuepl 184 81 0 74 1 0 1 1 0 8 0 pipepl 304 132 0 105 3 0 3 3 0 8 0 fdescpl 448 615 0 594 5 0 5 5 0 8 1 filepl 120 2633 0 2447 9 0 9 9 0 8 2 lockfpl 104 231 0 231 2 0 2 2 0 8 2 lockfspl 48 112 0 112 1 0 1 1 0 8 1 sessionpl 144 31 0 26 1 0 1 1 0 8 0 pgrppl 48 40 0 27 1 0 1 1 0 8 0 ucredpl 104 297 0 290 1 0 1 1 0 8 0 zombiepl 144 723 0 723 2 1 1 1 0 8 1 processpl 1152 628 0 594 4 0 4 4 0 8 0 procpl 664 983 0 939 6 0 6 6 0 8 1 sockpl 552 426 0 413 4 1 3 3 0 8 1 mcl64k 65536 24 0 23 1 0 1 1 0 8 0 mcl16k 16384 2 0 2 1 0 1 1 0 8 1 mcl12k 12288 2 0 2 1 0 1 1 0 8 1 mcl8k 8192 5 0 5 2 1 1 1 0 8 1 mcl4k 4096 2790 0 2735 15 6 9 15 0 8 1 mcl2k 2048 289 0 286 3 1 2 2 0 8 0 mtagpl 96 5 0 4 2 1 1 1 0 8 0 mbufpl 256 6327 0 6095 16 0 16 16 0 8 0 bufpl 272 2553 0 103 164 0 164 164 0 8 0 anonpl 24 109141 0 106957 40 1 39 39 0 186 19 amapchunkpl 152 14088 0 13707 24 0 24 24 0 158 7 amappl16 200 1889 0 1872 18 8 10 14 0 8 8 amappl15 192 6 0 6 1 1 0 1 0 8 0 amappl14 184 413 0 413 1 0 1 1 0 8 1 amappl13 176 117 0 113 1 0 1 1 0 8 0 amappl12 168 854 0 834 2 0 2 2 0 8 0 amappl11 160 17 0 17 1 1 0 1 0 8 0 amappl10 152 113 0 109 1 0 1 1 0 8 0 amappl9 144 272 0 272 1 1 0 1 0 8 0 amappl8 136 95 0 95 1 0 1 1 0 8 1 amappl7 128 142 0 136 1 0 1 1 0 8 0 amappl6 120 161 0 161 1 0 1 1 0 8 1 amappl5 112 94 0 89 1 0 1 1 0 8 0 amappl4 104 263 0 256 1 0 1 1 0 8 0 amappl3 96 2753 0 2671 4 0 4 4 0 8 1 amappl2 88 524 0 497 2 0 2 2 0 8 0 amappl1 80 10975 0 10671 13 0 13 13 0 8 3 amappl 88 4037 0 3907 5 0 5 5 0 92 1 uvmvnodes 80 105 0 0 3 0 3 3 0 8 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 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 6 0 2 1 0 1 1 0 8 0 uaddrrnd 24 615 0 594 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 615 0 594 1 0 1 1 0 8 0 vmmpekpl 168 6859 0 6829 2 0 2 2 0 8 0 vmmpepl 168 47732 0 46566 81 0 81 81 0 357 17 vmsppl 368 614 0 594 4 1 3 4 0 8 0 rwobjpl 40 16450 0 15860 11 1 10 11 0 8 0 pdppl 4096 1236 0 1188 100 48 52 82 0 8 4 pvpl 32 283427 0 277553 87 0 87 87 0 265 22 pmappl 216 614 0 594 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 541 0 62 14 0 14 14 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8347e1d1) at panic+0x1cf sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ad10c0,1,ffff80002f0ab3d8) at pool_do_get+0x5bc pool_get(ffffffff83ad10c0,1) at pool_get+0x11a sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c8fa7e8,ffff80002f0ab620,40,ffff80002f0ab570) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c8fa7e8,ffff80002f0ab620,ffff80002f0ab570) at sys_shmget+0x195 sys/kern/sysv_shm.c:501 syscall(ffff80002f0ab620) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002f0ab620) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6cb9d43b450, count: -8 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8347e1d1) at panic+0x1cf sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ad10c0,1,ffff80002f0ab3d8) at pool_do_get+0x5bc pool_get(ffffffff83ad10c0,1) at pool_get+0x11a sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c8fa7e8,ffff80002f0ab620,40,ffff80002f0ab570) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c8fa7e8,ffff80002f0ab620,ffff80002f0ab570) at sys_shmget+0x195 sys/kern/sysv_shm.c:501 syscall(ffff80002f0ab620) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002f0ab620) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6cb9d43b450, count: -8