panic: pool_do_get: shmpl free list modified: page 0xfffffd805f28a000; item addr 0xfffffd805f28ae00; offset 0x40=0x68b00695 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 370257 55933 32767 0x10 0 1 syz-executor * 55265 76597 32767 0x10 0x4000000 0K syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83367500) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff838d5228,1,ffff80002dbff888) at pool_do_get+0x5df pool_get(ffffffff838d5228,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c451cb8,ffff80002dbffae0,a8,ffff80002dbffa30) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c451cb8,ffff80002dbffae0,ffff80002dbffa30) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002dbffae0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002dbffae0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x4cc791c9b00, 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 0xfffffd805f28a000; item addr 0xfffffd805f28ae00; offset 0x40=0x68b00695 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83367500) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff838d5228,1,ffff80002dbff888) at pool_do_get+0x5df pool_get(ffffffff838d5228,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c451cb8,ffff80002dbffae0,a8,ffff80002dbffa30) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c451cb8,ffff80002dbffae0,ffff80002dbffa30) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002dbffae0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002dbffae0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x4cc791c9b00, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80002dbff6b0 rbx 0xffffffff837f9ddf cpu_info_full_primary+0x2ddf rdx 0xffff800001436b00 rcx 0xffff80003c451cb8 rax 0xffffffff837f8ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x145773b4c89949f1 r11 0xeb6fe86c8ed4d03e r12 0xffffffff837f9be0 cpu_info_full_primary+0x2be0 r13 0 r14 0 r15 0x1 rip 0xffffffff82d888f5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002dbff6a0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=55265 pid=76597 tcnt=2 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c451a20,0xffff80003c4502d8 process=0xffff80003c47d370 user=0xffff80002dbfa000, vmspace=0xfffffd800eaef210 estcpu=36, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 55933 370257 61587 32767 7 0x10 syz-executor 55933 169810 61587 32767 2 0x4000010 syz-executor 76597 221050 30554 32767 2 0x10 syz-executor *76597 55265 30554 32767 7 0x4000010 syz-executor 5302 184712 80376 32767 2 0x10 syz-executor 5302 30028 80376 32767 2 0x4000010 syz-executor 85200 374840 65203 0 2 0x2 syz-executor 4392 93863 31476 32767 2 0x10 syz-executor 4392 254712 31476 32767 3 0x4000090 msgwait syz-executor 4392 512714 31476 32767 3 0x4000090 fsleep syz-executor 98291 288325 0 0 3 0x14200 bored sosplice 61587 510018 41349 32767 3 0x90 nanoslp syz-executor 35454 398202 89749 32767 3 0x90 wait syz-executor 31476 504992 44501 32767 3 0x90 nanoslp syz-executor 80376 440429 88362 32767 3 0x90 nanoslp syz-executor 63577 159664 67194 32767 3 0x90 wait syz-executor 30554 301796 35412 32767 3 0x90 nanoslp syz-executor 60822 168930 73351 32767 3 0x90 nanoslp syz-executor 89749 201707 65203 0 3 0x82 wait syz-executor 44501 281389 65203 0 3 0x82 wait syz-executor 41349 419671 65203 0 3 0x82 wait syz-executor 73351 488717 65203 0 3 0x82 wait syz-executor 67194 187261 65203 0 3 0x82 wait syz-executor 35412 371763 65203 0 3 0x82 wait syz-executor 88362 419155 65203 0 3 0x82 wait syz-executor 65203 313158 44331 0 3 0x82 kqread syz-executor 44331 63240 94449 0 3 0x10008a sigsusp ksh 94449 279320 71383 0 3 0x98 kqread sshd-session 71383 184651 95412 0 3 0x92 kqread sshd-session 21292 35758 1 0 3 0x100083 ttyin getty 95412 248750 1 0 3 0x88 kqread sshd 16597 338682 64417 73 3 0x1100090 kqread syslogd 64417 172031 1 0 3 0x100082 sbwait syslogd 81773 32364 1 0 3 0x100080 kqread resolvd 52945 387917 61163 77 3 0x100092 kqread dhcpleased 57988 472481 61163 77 3 0x100092 kqread dhcpleased 61163 246534 1 0 3 0x80 kqread dhcpleased 59104 22723 0 0 3 0x14200 bored smr 47429 374114 0 0 2 0x14200 zerothread 82015 60803 0 0 3 0x14200 aiodoned aiodoned 25240 233731 0 0 3 0x14200 syncer update 80011 186118 0 0 3 0x14200 cleaner cleaner 41242 122313 0 0 3 0x14200 reaper reaper 73382 333299 0 0 3 0x14200 pgdaemon pagedaemon 86619 126842 0 0 3 0x14200 bored viomb 84640 135630 0 0 3 0x40014200 acpi0 acpi0 45411 135516 0 0 3 0x40014200 idle1 67183 338344 0 0 3 0x14200 bored softnet7 6983 321224 0 0 3 0x14200 bored softnet6 66784 263073 0 0 3 0x14200 bored softnet5 73088 383048 0 0 3 0x14200 bored softnet4 61803 218381 0 0 3 0x14200 bored softnet3 72649 41089 0 0 3 0x14200 bored softnet2 55672 382119 0 0 3 0x14200 bored softnet1 80127 23432 0 0 3 0x14200 bored softnet0 52416 212155 0 0 3 0x14200 bored systqmp 60221 191967 0 0 3 0x14200 bored systq 56183 189911 0 0 3 0x14200 tmoslp softclockmp 92487 356249 0 0 3 0x40014200 tmoslp softclock 22284 258363 0 0 3 0x40014200 idle0 1 410292 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex shmpl r = 0 (0xffffffff838d5240) #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:746 #7 Xsyscall+0x128 Process 76597 (syz-executor) thread 0xffff80003c451cb8 (55265) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff838d02f0) #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:746 #2 Xsyscall+0x128 exclusive mutex shmpl r = 0 (0xffffffff838d5240) #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:746 #7 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10194 10954K 10968K 166960K 11275 0 pcb 17 12K 12K 166960K 17 0 rtable 193 5K 6K 166960K 266 0 pf 29 16K 16K 166960K 31 0 ifaddr 38 6K 7K 166960K 44 0 ifgroup 46 2K 2K 166960K 50 0 sysctl 1 1K 9K 166960K 7 0 counters 66 36K 36K 166960K 68 0 ioctlops 0 0K 2K 166960K 30 0 iov 0 0K 24K 166960K 44 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1334 84K 84K 166960K 1373 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 4 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 20 0 dirhash 12 2K 2K 166960K 15 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 24 89K 129K 166960K 285 0 sigio 0 0K 0K 166960K 5 0 proc 58 99K 163K 166960K 499 0 subproc 65 4K 4K 166960K 92 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 36 0 in_multi 88 6K 7K 166960K 106 0 ether_multi 1 0K 0K 166960K 1 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 355 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 244 152K 174K 166960K 3991 0 UVM aobj 4 2K 3K 166960K 5 0 pinsyscall 45 90K 111K 166960K 1292 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 11 0 NDP 10 0K 1K 166960K 27 0 temp 43 8644K 8708K 166960K 4272 0 kqueue 13 20K 26K 166960K 47 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 52 0 49 1 0 1 1 0 8 0 rtentry 176 98 0 10 5 0 5 5 0 8 0 unpcb 144 123 0 104 1 0 1 1 0 8 0 syncache 336 6 0 6 1 0 1 1 0 8 1 tcpqe 32 3 0 3 1 0 1 1 0 8 1 tcpcb 736 68 0 61 2 0 2 2 0 8 1 arp 128 10 0 1 1 0 1 1 0 8 0 ipq 40 1 0 1 1 0 1 1 0 8 1 ipqe 40 2 0 2 1 0 1 1 0 8 1 inpcb 328 205 0 195 2 0 2 2 0 8 0 ip6q 72 2 0 0 1 0 1 1 0 8 0 ip6af 40 2 0 0 1 0 1 1 0 8 0 nd6 144 19 0 2 1 0 1 1 0 8 0 kcovpl 48 10 0 3 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 457 0 42 29 0 29 29 0 8 1 art_table 40 458 0 42 5 0 5 5 0 8 0 art_node 32 98 0 19 1 0 1 1 0 8 0 sysvmsgpl 40 6 0 5 1 0 1 1 0 8 0 semapl 112 15 0 5 1 0 1 1 0 8 0 shmpl 112 2 0 1 1 0 1 1 0 8 0 pool(0xffffffff838d5228:shmpl): page inconsistency: page 0xfffffd805f28a000; 33 on list, 1 missing, 35 items per page dirhash 1024 19 0 2 3 0 3 3 0 8 0 dino2pl 256 1722 0 214 95 0 95 95 0 8 0 ffsino 296 1722 0 214 117 0 117 117 0 8 0 nchpl 144 2085 0 407 63 0 63 63 0 8 0 uvmvnodes 80 1823 0 0 38 0 38 38 0 8 0 vnodes 216 1823 0 0 102 0 102 102 0 8 0 namei 1024 6377 0 6377 2 0 2 2 0 8 2 percpumem 16 49 0 1 1 0 1 1 0 8 0 kstatmem 264 24 0 2 2 0 2 2 0 8 0 scxspl 216 7917 0 7917 9 1 8 8 1 8 8 plimitpl 152 59 0 35 2 0 2 2 0 8 1 sigapl 424 557 0 498 8 0 8 8 0 8 0 knotepl 120 311 0 0 10 0 10 10 0 8 0 kqueuepl 224 64 0 54 1 0 1 1 0 8 0 pipepl 344 119 0 92 3 0 3 3 0 8 0 fdescpl 528 534 0 498 4 0 4 4 0 8 0 filepl 160 2218 0 2007 12 0 12 12 0 8 1 lockfpl 104 26 0 24 1 0 1 1 0 8 0 lockfspl 48 13 0 11 1 0 1 1 0 8 0 sessionpl 144 26 0 11 1 0 1 1 0 8 0 pgrppl 48 40 0 17 1 0 1 1 0 8 0 ucredpl 104 301 0 283 1 0 1 1 0 8 0 zombiepl 144 501 0 498 1 0 1 1 0 8 0 processpl 1232 557 0 498 7 1 6 6 0 8 0 procpl 664 789 0 725 7 0 7 7 0 8 0 sosppl 168 4 0 4 1 0 1 1 0 8 1 sockpl 752 414 0 382 5 0 5 5 0 8 1 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 110 0 0 14 0 14 14 0 8 0 mcl2k 2048 37 0 0 5 0 5 5 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 229 0 0 15 0 15 15 0 8 0 bufpl 280 3177 0 116 219 0 219 219 0 8 0 anonpl 32 7619 0 0 62 0 62 62 0 246 0 amapchunkpl 152 12898 0 12363 41 2 39 39 0 158 15 amappl16 200 2036 0 2013 16 2 14 14 0 8 10 amappl15 192 9 0 9 1 1 0 1 0 8 0 amappl14 184 107 0 97 1 0 1 1 0 8 0 amappl13 176 6 0 6 1 1 0 1 0 8 0 amappl12 168 1131 0 1095 2 0 2 2 0 8 0 amappl11 160 42 0 32 1 0 1 1 0 8 0 amappl10 152 2 0 2 1 1 0 1 0 8 0 amappl9 144 262 0 262 1 1 0 1 0 8 0 amappl8 136 23 0 21 1 0 1 1 0 8 0 amappl7 128 94 0 84 1 0 1 1 0 8 0 amappl6 120 168 0 165 1 0 1 1 0 8 0 amappl5 112 113 0 107 1 0 1 1 0 8 0 amappl4 104 264 0 249 1 0 1 1 0 8 0 amappl3 96 2086 0 1961 4 0 4 4 0 8 0 amappl2 88 604 0 551 2 0 2 2 0 8 0 amappl1 80 8965 0 8396 14 0 14 14 0 8 0 amappl 88 3338 0 3160 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 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 4 0 1 1 0 1 1 0 8 0 uaddrrnd 24 534 0 498 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 534 0 498 1 0 1 1 0 8 0 vmmpekpl 168 6014 0 5970 3 0 3 3 0 8 0 vmmpepl 168 40285 0 38223 109 0 109 109 0 357 8 vmsppl 488 533 0 498 7 1 6 6 0 8 1 rwobjpl 80 15719 0 13068 60 0 60 60 0 8 2 pdppl 4096 1076 0 996 110 24 86 100 0 8 6 pvpl 32 15065 0 0 123 1 122 123 0 265 0 pmappl 256 533 0 498 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 287 0 27 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(ffffffff83367500) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff838d5228,1,ffff80002dbff888) at pool_do_get+0x5df pool_get(ffffffff838d5228,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80003c451cb8,ffff80002dbffae0,a8,ffff80002dbffa30) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80003c451cb8,ffff80002dbffae0,ffff80002dbffa30) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002dbffae0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002dbffae0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x4cc791c9b00, 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: 0x7e9d232fc7c0, 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: 0x7e9d232fc7c0, count: -3