panic: pool_do_get: shmpl free list modified: page 0xfffffd806b62a000; item addr 0xfffffd806b62aaf0; offset 0x40=0x69f3c1a6 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *498245 61155 32767 0x10 0x4000000 1K syz-executor 240276 78423 32767 0x10 0 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83445d60) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff839a15c8,1,ffff80003c4412c8) at pool_do_get+0x5df pool_get(ffffffff839a15c8,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003b3f02c8,ffff80003c441520,101,ffff80003c441470) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003b3f02c8,ffff80003c441520,ffff80003c441470) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff80003c441520) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c441520) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x257343b780, 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 0xfffffd806b62a000; item addr 0xfffffd806b62aaf0; offset 0x40=0x69f3c1a6 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83445d60) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff839a15c8,1,ffff80003c4412c8) at pool_do_get+0x5df pool_get(ffffffff839a15c8,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003b3f02c8,ffff80003c441520,101,ffff80003c441470) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003b3f02c8,ffff80003c441520,ffff80003c441470) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff80003c441520) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c441520) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x257343b780, count: -8 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80003c4410f0 rbx 0xffff8000299aee07 rdx 0xffff8000015ce5c0 rcx 0xffff80003b3f02c8 rax 0xffff8000299adff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x97c815019a0886ca r11 0x2d534deef527947a r12 0xffff8000299aec08 r13 0 r14 0 r15 0x1 rip 0xffffffff8258e665 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c4410e0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=498245 pid=61155 tcnt=2 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=73, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003b3f1258,0xffffffff83a2cf28 process=0xffff80003b3e7040 user=0xffff80003c43c000, vmspace=0xfffffd806c20b9b8 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 61155 290078 4513 32767 2 0x10 syz-executor *61155 498245 4513 32767 7 0x4000010 syz-executor 52364 153746 70607 32767 2 0x10 syz-executor 78423 240276 26526 32767 7 0x10 syz-executor 78423 93121 26526 32767 2 0x4000010 syz-executor 76845 140795 19801 0 2 0 syz-executor 9317 354967 82022 32767 2 0x10 syz-executor 9317 211998 82022 32767 3 0x4000090 fsleep syz-executor 9317 265566 82022 32767 3 0x4000090 sbwait syz-executor 9317 420392 82022 32767 3 0x4000090 sbwait syz-executor 19801 136664 30859 0 3 0x82 wait syz-executor 21496 8381 49155 32767 2 0x10 syz-executor 21496 176498 49155 32767 3 0x4000090 kqsel syz-executor 21496 89703 49155 32767 3 0x4000090 fsleep syz-executor 20644 10371 30859 0 2 0x2 syz-executor 84882 325585 36354 32767 4 0x82010 syz-executor 84882 193966 36354 32767 2 0x4082010 syz-executor 84882 312894 36354 32767 3 0x4002010 suspend syz-executor 51479 455095 51085 0 3 0x100082 sbwait ndp 51085 112029 42780 0 3 0x10008a sigsusp sh 36354 140029 1 32767 3 0x90 wait syz-executor 70607 78693 54178 32767 3 0x90 nanoslp syz-executor 4513 375242 82470 32767 3 0x90 nanoslp syz-executor 82022 261031 60823 32767 3 0x90 nanoslp syz-executor 49155 248993 31470 32767 3 0x90 nanoslp syz-executor 42780 289044 63183 0 3 0x80 wait syz-executor 26526 78125 69399 32767 3 0x90 nanoslp syz-executor 54178 398377 30859 0 3 0x82 wait syz-executor 82470 136289 30859 0 3 0x82 wait syz-executor 31470 309535 30859 0 3 0x82 wait syz-executor 60823 340589 30859 0 3 0x82 wait syz-executor 63183 353480 30859 0 3 0x82 wait syz-executor 69399 68899 30859 0 3 0x82 wait syz-executor 30859 148179 18315 0 3 0x82 kqread syz-executor 18315 115475 51640 0 3 0x10008a sigsusp ksh 51640 235142 40362 0 3 0x98 kqread sshd-session 40362 277169 50503 0 3 0x92 kqread sshd-session 41303 406312 1 0 3 0x100083 ttyin getty 50503 407672 1 0 3 0x88 kqread sshd 23229 32267 80227 73 3 0x1100090 kqread syslogd 80227 103798 1 0 3 0x100082 sbwait syslogd 37042 497710 1 0 3 0x100080 kqread resolvd 62141 272915 4055 77 3 0x100092 kqread dhcpleased 11801 58827 4055 77 3 0x100092 kqread dhcpleased 4055 191161 1 0 3 0x80 kqread dhcpleased 26660 376089 0 0 3 0x14200 bored smr 20620 522196 0 0 2 0x14200 zerothread 73711 169839 0 0 3 0x14200 aiodoned aiodoned 31455 352573 0 0 3 0x14200 syncer update 34956 41700 0 0 3 0x14200 cleaner cleaner 99082 520678 0 0 3 0x14200 reaper reaper 35664 398448 0 0 3 0x14200 pgdaemon pagedaemon 99166 185740 0 0 3 0x14200 bored viomb 75336 79090 0 0 3 0x40014200 acpi0 acpi0 53038 196474 0 0 3 0x40014200 idle1 52680 341443 0 0 3 0x14200 bored softnet1 24902 328383 0 0 3 0x14200 bored softnet0 60991 144294 0 0 3 0x14200 bored systqmp 59231 324068 0 0 3 0x14200 bored systq 55846 83701 0 0 3 0x14200 tmoslp softclockmp 98260 188449 0 0 3 0x40014200 tmoslp softclock 95775 382340 0 0 3 0x40014200 idle0 1 370500 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex shmpl r = 0 (0xffffffff839a15e0) #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+0x4b4 sys/kern/kern_lock.c:487 #2 pool_get+0x124 sys/kern/subr_pool.c:585 #3 shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 #4 sys_shmget+0x195 sys/kern/sysv_shm.c:484 #5 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #6 Xsyscall+0x128 Process 61155 (syz-executor) thread 0xffff80003b3f02c8 (498245) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8397a7c0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 syscall+0xaf4 mi_syscall sys/sys/syscall_mi.h:175 [inline] #1 syscall+0xaf4 sys/arch/amd64/amd64/trap.c:783 #2 Xsyscall+0x128 exclusive mutex shmpl r = 0 (0xffffffff839a15e0) #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+0x4b4 sys/kern/kern_lock.c:487 #2 pool_get+0x124 sys/kern/subr_pool.c:585 #3 shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 #4 sys_shmget+0x195 sys/kern/sysv_shm.c:484 #5 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #6 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11054 12017K 12034K 166960K 12148 0 pcb 17 12K 12K 166960K 17 0 rtable 213 6K 6K 166960K 349 0 pf 29 16K 16K 166960K 31 0 ifaddr 38 6K 7K 166960K 44 0 ifgroup 46 2K 2K 166960K 50 0 sysctl 3 1K 9K 166960K 7 0 counters 68 36K 37K 166960K 70 0 ioctlops 0 0K 2K 166960K 33 0 iov 0 0K 12K 166960K 8 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1296 82K 82K 166960K 1545 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 8 0K 1K 166960K 9 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 26 97K 125K 166960K 282 0 proc 58 99K 180K 166960K 505 0 subproc 74 4K 5K 166960K 191 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 21 0 in_multi 88 6K 7K 166960K 105 0 ether_multi 1 0K 0K 166960K 2 0 mrt 0 0K 0K 166960K 15 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 85 387K 387K 166960K 85 0 exec 0 0K 1K 166960K 378 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 246 171K 178K 166960K 3863 0 UVM aobj 7 2K 2K 166960K 9 0 pinsyscall 48 96K 114K 166960K 1336 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 1 0K 0K 166960K 6 0 NDP 10 0K 2K 166960K 27 0 temp 40 9074K 9138K 166960K 4445 0 kqueue 13 20K 23K 166960K 36 0 SYN cache 2 16K 16K 166960K 2 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 42 0 37 1 0 1 1 0 8 0 rtentry 176 111 0 13 5 0 5 5 0 8 0 unpcb 144 215 0 200 6 0 6 6 0 8 5 syncache 336 3 0 3 1 1 0 1 0 8 0 tcpcb 736 54 0 48 1 0 1 1 0 8 0 arp 136 18 0 2 1 0 1 1 0 8 0 ipq 40 1 0 1 1 0 1 1 0 8 1 ipqe 40 3 0 3 1 0 1 1 0 8 1 inpcb 328 167 0 157 4 2 2 4 0 8 1 ip6q 72 1 0 0 1 0 1 1 0 8 0 ip6af 40 1 0 0 1 0 1 1 0 8 0 nd6 152 24 0 4 1 0 1 1 0 8 0 kcovpl 48 21 0 13 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 454 0 46 29 1 28 29 0 8 0 art_table 40 455 0 46 5 0 5 5 0 8 0 art_node 32 111 0 22 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 3 1 0 1 1 0 8 1 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 6 0 0 1 0 1 1 0 8 0 shmpl 112 6 0 2 1 0 1 1 0 8 0 pool(0xffffffff839a15c8:shmpl): page inconsistency: page 0xfffffd806b62a000; 30 on list, 4 missing, 35 items per page dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1748 0 274 93 0 93 93 0 8 0 ffsino 296 1748 0 274 114 0 114 114 0 8 0 nchpl 144 2059 0 360 64 0 64 64 0 8 0 vnodes 216 1948 0 0 109 0 109 109 0 8 0 namei 1024 6215 0 6215 1 0 1 1 0 8 1 percpumem 16 50 0 1 1 0 1 1 0 8 0 kstatmem 264 25 0 2 2 0 2 2 0 8 0 scxspl 216 6689 0 6689 4 3 1 3 1 8 1 plimitpl 152 105 0 80 3 1 2 2 0 8 0 sigapl 424 539 0 485 7 0 7 7 0 8 0 knotepl 120 58 0 0 2 0 2 2 0 8 0 kqueuepl 224 40 0 30 1 0 1 1 0 8 0 pipepl 344 225 0 195 9 0 9 9 0 8 6 fdescpl 528 523 0 485 4 0 4 4 0 8 0 filepl 160 2520 0 2302 15 0 15 15 0 8 5 lockfpl 104 71 0 69 1 0 1 1 0 8 0 lockfspl 48 16 0 14 1 0 1 1 0 8 0 sessionpl 144 76 0 60 1 0 1 1 0 8 0 pgrppl 48 102 0 78 1 0 1 1 0 8 0 ucredpl 104 429 0 412 1 0 1 1 0 8 0 zombiepl 144 485 0 485 1 0 1 1 0 8 1 processpl 1232 539 0 485 5 0 5 5 0 8 0 procpl 664 699 0 636 7 0 7 7 0 8 0 sockpl 752 425 0 395 17 5 12 16 0 8 8 mcl64k 65536 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 113 0 0 15 0 15 15 0 8 0 mcl2k 2048 24 0 0 3 0 3 3 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 221 0 0 14 0 14 14 0 8 0 bufpl 280 2394 0 102 164 0 164 164 0 8 0 anonpl 32 7410 0 0 60 0 60 60 0 246 0 amapchunkpl 152 11521 0 10821 37 3 34 34 0 158 6 amappl16 200 2478 0 2462 19 10 9 14 0 8 7 amappl15 192 7 0 6 1 0 1 1 0 8 0 amappl14 184 399 0 397 1 0 1 1 0 8 0 amappl13 176 113 0 102 1 0 1 1 0 8 0 amappl12 168 759 0 725 2 0 2 2 0 8 0 amappl11 160 5 0 5 1 1 0 1 0 8 0 amappl10 152 58 0 48 1 0 1 1 0 8 0 amappl9 144 294 0 294 1 1 0 1 0 8 0 amappl8 136 108 0 106 1 0 1 1 0 8 0 amappl7 128 152 0 138 1 0 1 1 0 8 0 amappl6 120 183 0 181 1 0 1 1 0 8 0 amappl5 112 85 0 78 1 0 1 1 0 8 0 amappl4 104 250 0 234 1 0 1 1 0 8 0 amappl3 96 2012 0 1891 5 1 4 4 0 8 0 amappl2 88 497 0 443 2 0 2 2 0 8 0 amappl1 80 9367 0 8768 14 0 14 14 0 8 0 amappl 88 3175 0 2999 5 0 5 5 0 92 0 uvmvnodes 80 104 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 18 0 17 1 0 1 1 0 8 0 aobjpl 72 8 0 2 1 0 1 1 0 8 0 uaddrrnd 24 523 0 485 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 523 0 485 1 0 1 1 0 8 0 vmmpekpl 168 6259 0 6219 3 0 3 3 0 8 0 vmmpepl 168 41608 0 39554 100 1 99 100 0 357 9 vmsppl 488 522 0 485 7 1 6 6 0 8 0 rwobjpl 80 14812 0 13818 25 0 25 25 0 8 2 pdppl 4096 1053 0 970 111 28 83 97 0 8 0 pvpl 32 16455 0 0 133 0 133 133 0 265 0 pmappl 256 522 0 485 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 281 0 33 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8389bff0) 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(ffffffff83979fc0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff83979fc0) at __mp_lock+0x192 sys/kern/kern_lock.c:173 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862 Xsoftclock() at Xsoftclock+0x27 end of kernel end trace frame: 0x775005432ea0, count: 8 ddb{0}> trace x86_ipi_db(ffffffff8389bff0) 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(ffffffff83979fc0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff83979fc0) at __mp_lock+0x192 sys/kern/kern_lock.c:173 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:862 Xsoftclock() at Xsoftclock+0x27 end of kernel end trace frame: 0x775005432ea0, 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(ffffffff83445d60) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff839a15c8,1,ffff80003c4412c8) at pool_do_get+0x5df pool_get(ffffffff839a15c8,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003b3f02c8,ffff80003c441520,101,ffff80003c441470) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003b3f02c8,ffff80003c441520,ffff80003c441470) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff80003c441520) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c441520) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x257343b780, count: 7 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83445d60) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff839a15c8,1,ffff80003c4412c8) at pool_do_get+0x5df pool_get(ffffffff839a15c8,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003b3f02c8,ffff80003c441520,101,ffff80003c441470) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003b3f02c8,ffff80003c441520,ffff80003c441470) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff80003c441520) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c441520) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x257343b780, count: -8