panic: pool_do_get: shmpl free list modified: page 0xfffffd8074897000; item addr 0xfffffd8074897868; offset 0x40=0x80000b0 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 78594 811 0 0 0 0 syz-executor *289075 811 0 0 0x4000000 1K syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4d39) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8396d950,1,ffff80002a3565d8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8396d950,1) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000ffff3200,ffff80002a356830,40,ffff80002a356780) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000ffff3200,ffff80002a356830,ffff80002a356780) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80002a356830) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a356830) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00ce62fae0, 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: pool_do_get: shmpl free list modified: page 0xfffffd8074897000; item addr 0xfffffd8074897868; offset 0x40=0x80000b0 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4d39) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8396d950,1,ffff80002a3565d8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8396d950,1) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000ffff3200,ffff80002a356830,40,ffff80002a356780) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000ffff3200,ffff80002a356830,ffff80002a356780) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80002a356830) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a356830) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00ce62fae0, count: -8 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a356410 rbx 0xffff8000299dedd7 rdx 0xffff800001484bc0 rcx 0xffff8000ffff3200 rax 0xffff8000299ddff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x9222c39040d9f16b r11 0xe7273cc71926a7e r12 0xffff8000299debd8 r13 0 r14 0 r15 0x1 rip 0xffffffff82b0f3a5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a356400 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=289075 pid=811 tcnt=2 stat=onproc flags process=0 proc=4000000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000ffff2a50,0xffffffff8395fb18 process=0xffff80003b01d380 user=0xffff80002a351000, vmspace=0xfffffd805c8bd988 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 811 78594 7219 0 7 0 syz-executor * 811 289075 7219 0 7 0x4000000 syz-executor 94915 352182 32899 0 3 0x82 sysctllk syz-executor 76389 517156 32899 0 3 0x82 sysctllk syz-executor 88059 42568 32899 0 3 0x82 sysctllk syz-executor 92117 476550 0 0 3 0x14200 acct acct 92548 71240 32899 0 3 0x82 sysctllk syz-executor 81161 322904 32899 0 3 0x82 sysctllk syz-executor 48287 17132 32899 0 3 0x82 sysctllk syz-executor 58293 185127 1 0 3 0x82 sysctllk getty 20604 427248 1 0 3 0 vmmapbsy syz-executor 20604 452362 1 0 3 0x4000000 vmmapbsy syz-executor 20604 226723 1 0 3 0x4000000 fltagain2 syz-executor 20604 90779 1 0 3 0x4000080 pipeiolk syz-executor 20604 456994 1 0 3 0x4000000 pipecl syz-executor 20604 468463 1 0 3 0x4000000 fltagain2 syz-executor 66933 178712 0 0 3 0x14200 bored sosplice 7219 117395 32899 0 3 0x82 nanoslp syz-executor 85808 112357 32899 0 3 0x82 nanoslp syz-executor 32899 78477 58525 0 3 0x82 kqread syz-executor 58525 448691 66100 0 3 0x10008a sigsusp ksh 66100 45743 62048 0 3 0x98 kqread sshd-session 62048 182597 37760 0 3 0x92 kqread sshd-session 37760 517928 1 0 3 0x88 kqread sshd 63155 132863 61579 74 3 0x1100092 bpf pflogd 61579 437507 1 0 3 0x80 sbwait pflogd 73656 173811 40420 73 3 0x1100090 kqread syslogd 40420 339418 1 0 3 0x100082 sbwait syslogd 79969 441700 1 0 3 0x100080 kqread resolvd 41430 335453 93190 77 3 0x100092 sysctllk dhcpleased 70976 352747 93190 77 3 0x100092 kqread dhcpleased 93190 460860 1 0 3 0x80 kqread dhcpleased 4783 358899 0 0 3 0x14200 bored smr 68949 362702 0 0 3 0x14200 pgzero zerothread 90864 404621 0 0 3 0x14200 aiodoned aiodoned 86281 384319 0 0 3 0x14200 syncer update 73570 474956 0 0 3 0x14200 cleaner cleaner 91891 79631 0 0 3 0x14200 reaper reaper 27346 29343 0 0 3 0x14200 pgdaemon pagedaemon 46774 173815 0 0 3 0x14200 bored viomb 36938 461879 0 0 3 0x40014200 acpi0 acpi0 83089 479714 0 0 3 0x40014200 idle1 86383 14549 0 0 3 0x14200 bored softnet3 25962 361842 0 0 3 0x14200 bored softnet2 57716 257123 0 0 3 0x14200 bored softnet1 35327 250863 0 0 2 0x14200 softnet0 44043 511167 0 0 3 0x14200 bored systqmp 81565 333519 0 0 3 0x14200 bored systq 15994 486813 0 0 3 0x14200 tmoslp softclockmp 79817 153379 0 0 3 0x40014200 tmoslp softclock 75300 381191 0 0 3 0x40014200 idle0 1 56677 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex shmpl r = 0 (0xffffffff8396d968) #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:311 #2 mtx_enter+0x62 sys/kern/kern_lock.c:261 #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:742 #7 Xsyscall+0x128 Process 811 (syz-executor) thread 0xffff8000ffff3200 (289075) Process 20604 (syz-executor) thread 0xffff80002a2967d0 (452362) Process 20604 (syz-executor) thread 0xffff80002a2974a0 (468463) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10241 11033K 12329K 166960K 13918 0 pcb 19 16K 17K 166960K 449 0 rtable 136 11K 11K 166960K 792 0 pf 42 19K 23K 166960K 737 0 ifaddr 28 4K 8K 166960K 160 0 ifgroup 54 2K 3K 166960K 270 0 sysctl 4 1K 9K 166960K 20 0 counters 72 37K 38K 166960K 708 0 ioctlops 0 0K 8K 166960K 2292 0 iov 0 0K 24K 166960K 238 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1509 95K 96K 166960K 3491 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 33 0 VM map 2 1K 1K 166960K 2 0 sem 22 17K 17K 166960K 256 0 dirhash 12 2K 2K 166960K 90 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 13 27K 97K 166960K 2519 0 sigio 0 0K 0K 166960K 48 0 proc 64 79K 127K 166960K 844 0 subproc 27 1K 4K 166960K 84 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 320 0 in_multi 39 2K 7K 166960K 237 0 ether_multi 1 0K 0K 166960K 36 0 mrt 1 0K 0K 166960K 26 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 247 1102K 1102K 166960K 247 0 exec 0 0K 1K 166960K 801 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 3 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 199 124K 182K 166960K 26199 0 UVM aobj 117 5K 6K 166960K 122 0 pinsyscall 38 76K 108K 166960K 3685 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 1K 166960K 187 0 NDP 12 0K 1K 166960K 105 0 temp 62 8695K 8944K 166960K 124986 0 kqueue 13 20K 32K 166960K 534 0 SYN cache 2 8K 16K 166960K 3 0 ddb{1}> 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 120 322 0 319 5 4 1 3 0 8 0 rtentry 176 264 0 221 6 0 6 6 0 8 0 unpcb 144 1702 0 1683 17 16 1 6 0 8 0 syncache 336 11 0 11 2 2 0 1 0 8 0 tcpcb 736 1038 0 1034 33 32 1 13 0 8 0 arp 128 60 0 53 1 0 1 1 0 8 0 inpcb 328 3151 0 3141 39 37 2 12 0 8 0 nd6 144 32 0 23 1 0 1 1 0 8 0 pkpcb 40 19 0 19 7 6 1 1 0 8 1 kcovpl 48 9 0 6 1 0 1 1 0 8 0 mppekey 1024 2 0 2 2 2 0 1 0 8 0 ppxss 1192 298 0 295 8 7 1 1 0 8 0 pppxif 1504 15 0 15 10 10 0 1 0 8 0 pfstscr 40 3 0 3 3 3 0 1 0 8 0 pffrag 232 8 0 8 1 1 0 1 0 482 0 pffrnode 88 8 0 8 1 1 0 1 0 8 0 pffrent 40 21 0 21 1 1 0 1 0 8 0 pfosfp 40 1429 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1429 0 714 21 0 21 21 0 8 0 pfrktable 1344 1 0 0 1 0 1 1 0 8 0 pfanchor 1288 5 0 1 1 0 1 1 0 8 0 pftag 88 3 0 0 1 0 1 1 0 8 0 pfqueue 320 2 0 2 2 2 0 1 0 8 0 pfstitem 24 181 0 137 1 0 1 1 0 8 0 pfstkey 128 190 0 146 3 1 2 3 0 8 0 pfstate 384 186 0 142 9 2 7 9 0 8 0 pfrule 1344 198 0 181 4 2 2 2 0 8 0 rttmr 136 7 0 7 3 3 0 1 0 8 0 art_heap8 4096 5 0 2 5 2 3 5 0 8 0 art_heap4 256 1078 0 868 32 14 18 30 0 8 0 art_table 32 1083 0 870 4 0 4 4 0 8 0 art_node 16 255 0 219 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 6 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 248 0 228 1 0 1 1 0 8 0 shmpl 112 119 0 5 4 0 4 4 0 8 0 pool(0xffffffff8396d950:shmpl): page inconsistency: page 0xfffffd8074897000; 25 on list, 9 missing, 35 items per page dirhash 1024 72 0 55 3 0 3 3 0 8 0 dino2pl 256 6333 0 4824 95 0 95 95 0 8 0 ffsino 288 6333 0 4824 109 1 108 109 0 8 0 nchpl 144 9871 0 8164 64 0 64 64 0 8 0 rtmask 32 16 0 14 10 9 1 1 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 34964 0 34964 7 6 1 3 0 8 1 percpumem 16 369 0 318 1 0 1 1 0 8 0 kstatmem 264 180 0 150 6 3 3 3 0 8 0 acpiwqpl 32 2 0 2 1 0 1 1 1 8 1 scsiplug 72 8 0 8 6 6 0 1 0 8 0 scxspl 216 69476 0 69476 21 20 1 8 1 8 1 plimitpl 152 791 0 773 1 0 1 1 0 8 0 sigapl 424 2829 0 2782 7 1 6 7 0 8 0 knotepl 120 549 0 0 17 0 17 17 0 8 0 kqueuepl 224 1145 0 1136 14 13 1 5 0 8 0 pipepl 336 474 0 445 6 3 3 6 0 8 0 fdescpl 520 2804 0 2777 3 0 3 3 0 8 0 filepl 160 20245 0 20074 38 27 11 18 0 8 0 lockfpl 104 1403 0 1401 2 1 1 2 0 8 0 lockfspl 48 470 0 468 1 0 1 1 0 8 0 sessionpl 144 29 0 21 1 0 1 1 0 8 0 pgrppl 48 137 0 120 1 0 1 1 0 8 0 ucredpl 104 3260 0 3247 1 0 1 1 0 8 0 zombiepl 144 3555 0 3554 2 1 1 1 0 8 0 processpl 1240 2829 0 2782 5 0 5 5 0 8 0 procpl 656 7412 0 7359 8 2 6 7 0 8 0 srpgc 96 24 0 24 7 7 0 1 0 8 0 sosppl 168 15 0 15 5 5 0 1 0 8 0 sockpl 728 5259 0 5227 71 67 4 18 0 8 0 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 114 0 0 15 0 15 15 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 66 0 0 7 0 7 7 0 8 0 mtagpl 96 19 0 0 1 0 1 1 0 8 0 mbufpl 256 457 0 0 23 0 23 23 0 8 0 bufpl 280 28861 0 22719 440 0 440 440 0 8 0 anonpl 32 13563 0 0 111 1 110 110 0 246 0 amapchunkpl 152 101318 0 100899 58 36 22 33 0 158 0 amappl16 200 12740 0 12585 105 91 14 33 0 8 0 amappl15 192 41 0 41 1 1 0 1 0 8 0 amappl14 184 128 0 116 1 0 1 1 0 8 0 amappl13 176 28 0 28 2 2 0 1 0 8 0 amappl12 168 3471 0 3450 4 2 2 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 144 322 0 321 1 0 1 1 0 8 0 amappl8 136 19 0 16 1 0 1 1 0 8 0 amappl7 128 122 0 109 1 0 1 1 0 8 0 amappl6 120 199 0 195 1 0 1 1 0 8 0 amappl5 112 156 0 145 1 0 1 1 0 8 0 amappl4 104 352 0 332 1 0 1 1 0 8 0 amappl3 96 18195 0 18115 4 0 4 4 0 8 0 amappl2 88 721 0 657 2 0 2 2 0 8 0 amappl1 80 19341 0 18749 17 2 15 16 0 8 0 amappl 88 25172 0 25043 5 0 5 5 0 92 0 dma32768 32768 1 0 1 1 1 0 1 0 8 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 2 0 2 2 2 0 1 0 8 0 dma1024 1024 3 0 2 1 0 1 1 0 8 0 dma256 256 7 0 7 2 2 0 1 0 8 0 dma128 128 256 0 256 4 4 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 8 0 8 2 2 0 1 0 8 0 dma16 16 20 0 19 1 0 1 1 0 8 0 aobjpl 72 121 0 5 3 0 3 3 0 8 0 uaddrrnd 24 2804 0 2777 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2804 0 2777 1 0 1 1 0 8 0 vmmpekpl 168 22331 0 22265 4 0 4 4 0 8 0 vmmpepl 168 187177 0 185373 122 22 100 118 0 357 0 vmsppl 480 2803 0 2777 6 2 4 5 0 8 0 rwobjpl 72 57457 0 50401 138 9 129 135 0 8 0 pdppl 4096 5615 0 5554 109 48 61 87 0 8 0 pvpl 32 21843 0 0 177 0 177 177 0 265 0 pmappl 256 2803 0 2777 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 461 0 116 11 0 11 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff838a2ff0) 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 __mp_lock(ffffffff83901df0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff83901df0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x12a sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 end of kernel end trace frame: 0x7080172ddf70, count: 8 ddb{0}> trace x86_ipi_db(ffffffff838a2ff0) 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 __mp_lock(ffffffff83901df0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff83901df0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x12a sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 end of kernel end trace frame: 0x7080172ddf70, count: -7 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4d39) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8396d950,1,ffff80002a3565d8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8396d950,1) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000ffff3200,ffff80002a356830,40,ffff80002a356780) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000ffff3200,ffff80002a356830,ffff80002a356780) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80002a356830) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a356830) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00ce62fae0, count: 7 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833d4d39) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8396d950,1,ffff80002a3565d8) at pool_do_get+0x5ea sys/kern/subr_pool.c:-1 pool_get(ffffffff8396d950,1) at pool_get+0x149 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000ffff3200,ffff80002a356830,40,ffff80002a356780) at shmget_allocate_segment+0x1a7 sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000ffff3200,ffff80002a356830,ffff80002a356780) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80002a356830) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a356830) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc00ce62fae0, count: -8