panic: pool_do_get: shmpl free list modified: page 0xfffffd806b210000; item addr 0xfffffd806b210bd0; offset 0x40=0x69fe754b Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 193420 73858 32767 0x10 0 1 syz-executor * 76315 8344 32767 0x10 0x4000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834446fb) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ac7490,1,ffff8000383c29c8) at pool_do_get+0x5df pool_get(ffffffff83ac7490,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000fffe7ca8,ffff8000383c2c20,1b4,ffff8000383c2b70) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000fffe7ca8,ffff8000383c2c20,ffff8000383c2b70) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff8000383c2c20) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000383c2c20) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x9fc0d0f5a00, 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 0xfffffd806b210000; item addr 0xfffffd806b210bd0; offset 0x40=0x69fe754b ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834446fb) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ac7490,1,ffff8000383c29c8) at pool_do_get+0x5df pool_get(ffffffff83ac7490,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000fffe7ca8,ffff8000383c2c20,1b4,ffff8000383c2b70) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000fffe7ca8,ffff8000383c2c20,ffff8000383c2b70) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff8000383c2c20) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000383c2c20) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x9fc0d0f5a00, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000383c27f0 rbx 0xffffffff83915e07 cpu_info_full_primary+0x2e07 rdx 0 rcx 0xffff8000fffe7ca8 rax 0xffffffff83914ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xc019084c13adcc19 r11 0xf94d8651f727566f r12 0xffffffff83915c08 cpu_info_full_primary+0x2c08 r13 0 r14 0 r15 0x1 rip 0xffffffff8259c4c5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff8000383c27e0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=76315 pid=8344 tcnt=3 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=0xffff8000fffe6fb0,0xffff8000fffe6a90 process=0xffff8000fffe09c0 user=0xffff8000383bd000, vmspace=0xfffffd806c7819b8 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 12515 73178 90341 0 2 0x100000 sh 73858 193420 11906 32767 7 0x10 syz-executor 73858 515268 11906 32767 2 0x4000090 syz-executor 547 155287 60114 0 2 0 syz-executor 60114 343404 55909 0 3 0x82 wait syz-executor 8344 464825 38812 32767 2 0x10 syz-executor * 8344 76315 38812 32767 7 0x4000010 syz-executor 8344 362412 38812 32767 3 0x4000090 fsleep syz-executor 86009 467846 43235 0 2 0x2 arp 43235 59383 29054 0 3 0x10008a sigsusp sh 90341 32793 59501 0 3 0x10008a sigsusp sh 97096 56135 99388 32767 3 0x90 piperd syz-executor 54122 395040 64752 32767 3 0x90 piperd syz-executor 29054 351689 49969 0 3 0x80 wait syz-executor 64752 57306 55909 0 3 0x82 wait syz-executor 99388 262392 55909 0 3 0x82 wait syz-executor 49969 302060 55909 0 3 0x82 wait syz-executor 38812 261933 82860 32767 3 0x90 nanoslp syz-executor 59501 440002 21955 0 3 0x80 wait syz-executor 11906 389958 12716 32767 3 0x90 nanoslp syz-executor 82860 403599 55909 0 3 0x82 wait syz-executor 21955 522952 55909 0 3 0x82 wait syz-executor 12716 166035 55909 0 3 0x82 wait syz-executor 55909 4298 8950 0 3 0x82 nanoslp syz-executor 8950 432616 90013 0 3 0x10008a sigsusp ksh 90013 427438 15155 0 3 0x98 kqread sshd-session 15155 117569 54947 0 3 0x92 kqread sshd-session 68378 398937 1 0 3 0x100083 ttyin getty 54947 220330 1 0 3 0x88 kqread sshd 51626 289546 72968 73 3 0x1100090 kqread syslogd 72968 507580 1 0 3 0x100082 sbwait syslogd 6720 256792 1 0 3 0x100080 kqread resolvd 17115 434953 80462 77 3 0x100092 kqread dhcpleased 30468 680 80462 77 3 0x100092 kqread dhcpleased 80462 233560 1 0 3 0x80 kqread dhcpleased 16262 199648 0 0 3 0x14200 bored smr 91906 422337 0 0 2 0x14200 zerothread 568 143880 0 0 3 0x14200 aiodoned aiodoned 86919 217706 0 0 3 0x14200 syncer update 25230 72345 0 0 3 0x14200 cleaner cleaner 98330 410433 0 0 3 0x14200 reaper reaper 64735 365320 0 0 3 0x14200 pgdaemon pagedaemon 50185 476647 0 0 3 0x14200 bored viomb 97946 261322 0 0 3 0x40014200 acpi0 acpi0 39810 513379 0 0 3 0x40014200 idle1 50335 349640 0 0 3 0x14200 bored softnet1 7858 73492 0 0 3 0x14200 bored softnet0 52414 351128 0 0 3 0x14200 bored systqmp 23405 209533 0 0 3 0x14200 bored systq 88503 488367 0 0 3 0x14200 tmoslp softclockmp 694 181036 0 0 3 0x40014200 tmoslp softclock 9079 263853 0 0 3 0x40014200 idle0 1 235425 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 (0xffffffff83ac74a8) #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 8344 (syz-executor) thread 0xffff8000fffe7ca8 (76315) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83a37d80) #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 (0xffffffff83ac74a8) #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{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11050 12014K 12034K 166960K 12165 0 pcb 17 12K 12K 166960K 17 0 rtable 163 4K 7K 166960K 486 0 pf 27 16K 16K 166960K 44 0 ifaddr 30 5K 7K 166960K 66 0 ifgroup 42 1K 2K 166960K 75 0 sysctl 1 1K 9K 166960K 6 0 counters 66 36K 37K 166960K 82 0 ioctlops 0 0K 2K 166960K 33 0 iov 0 0K 16K 166960K 24 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1350 85K 85K 166960K 1790 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 6 0K 1K 166960K 8 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 22 81K 135K 166960K 465 0 sigio 0 0K 0K 166960K 1 0 proc 58 99K 196K 166960K 667 0 subproc 63 3K 8K 166960K 504 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 11 0 in_multi 57 4K 7K 166960K 148 0 ether_multi 1 0K 0K 166960K 2 0 mrt 0 0K 0K 166960K 3 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 79 360K 360K 166960K 79 0 exec 0 0K 1K 166960K 470 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 197 144K 214K 166960K 4376 0 UVM aobj 6 2K 2K 166960K 7 0 pinsyscall 44 88K 116K 166960K 1656 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 17 1K 2K 166960K 41 0 temp 32 9074K 9138K 166960K 5627 0 kqueue 13 20K 26K 166960K 39 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 47 0 44 1 0 1 1 0 8 0 rtentry 176 162 0 89 5 0 5 5 0 8 1 unpcb 144 339 0 324 11 0 11 11 0 8 10 syncache 336 4 0 4 1 0 1 1 0 8 1 tcpcb 736 45 0 41 2 0 2 2 0 8 1 arp 136 29 0 16 1 0 1 1 0 8 0 inpcb 328 143 0 136 2 0 2 2 0 8 1 nd6 152 36 0 24 1 0 1 1 0 8 0 kcovpl 48 56 0 49 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 642 0 356 29 4 25 29 0 8 5 art_table 40 643 0 356 5 0 5 5 0 8 1 art_node 32 162 0 95 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 2 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 4 0 0 1 0 1 1 0 8 0 shmpl 112 4 0 1 1 0 1 1 0 8 0 pool(0xffffffff83ac7490:shmpl): page inconsistency: page 0xfffffd806b210000; 31 on list, 3 missing, 35 items per page dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1698 0 183 95 0 95 95 0 8 0 ffsino 296 1698 0 183 117 0 117 117 0 8 0 nchpl 144 1999 0 255 65 0 65 65 0 8 0 vnodes 216 2211 0 0 123 0 123 123 0 8 0 namei 1024 6830 0 6830 2 0 2 2 0 8 2 percpumem 16 56 0 8 1 0 1 1 0 8 0 kstatmem 264 37 0 16 2 0 2 2 0 8 0 scxspl 216 6775 0 6775 4 2 2 3 1 8 2 plimitpl 152 134 0 113 2 0 2 2 0 8 0 sigapl 424 653 0 603 8 0 8 8 0 8 0 knotepl 120 535 0 0 17 0 17 17 0 8 0 kqueuepl 224 39 0 30 1 0 1 1 0 8 0 pipepl 344 267 0 240 4 0 4 4 0 8 0 fdescpl 528 637 0 603 4 0 4 4 0 8 0 filepl 160 2770 0 2581 21 2 19 21 0 8 8 lockfpl 104 33 0 31 1 0 1 1 0 8 0 lockfspl 48 13 0 11 1 0 1 1 0 8 0 sessionpl 144 72 0 58 1 0 1 1 0 8 0 pgrppl 48 130 0 109 1 0 1 1 0 8 0 ucredpl 104 186 0 171 1 0 1 1 0 8 0 zombiepl 144 603 0 603 1 0 1 1 0 8 1 processpl 1232 653 0 603 5 0 5 5 0 8 0 procpl 664 777 0 724 6 0 6 6 0 8 1 sosppl 176 1 0 1 1 0 1 1 0 8 1 sockpl 752 530 0 505 31 20 11 31 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 119 0 0 15 0 15 15 0 8 0 mcl2k 2048 23 0 0 3 0 3 3 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 210 0 0 14 0 14 14 0 8 0 bufpl 280 2460 0 102 169 0 169 169 0 8 0 anonpl 32 5386 0 0 44 0 44 44 0 246 0 amapchunkpl 152 12647 0 12267 29 0 29 29 0 158 11 amappl16 200 2073 0 2062 5 2 3 5 0 8 2 amappl15 192 95 0 95 1 1 0 1 0 8 0 amappl14 184 466 0 463 1 0 1 1 0 8 0 amappl13 176 121 0 110 1 0 1 1 0 8 0 amappl12 168 889 0 860 2 0 2 2 0 8 0 amappl11 160 3 0 3 1 1 0 1 0 8 0 amappl10 152 82 0 71 1 0 1 1 0 8 0 amappl9 144 262 0 262 1 1 0 1 0 8 0 amappl8 136 123 0 122 1 0 1 1 0 8 0 amappl7 128 145 0 133 1 0 1 1 0 8 0 amappl6 120 235 0 232 1 0 1 1 0 8 0 amappl5 112 110 0 103 1 0 1 1 0 8 0 amappl4 104 261 0 245 1 0 1 1 0 8 0 amappl3 96 2260 0 2168 5 1 4 4 0 8 1 amappl2 88 524 0 471 2 0 2 2 0 8 0 amappl1 80 10455 0 9882 14 0 14 14 0 8 0 amappl 88 3578 0 3447 5 0 5 5 0 92 1 uvmvnodes 80 101 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 6 0 1 1 0 1 1 0 8 0 uaddrrnd 24 637 0 603 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 637 0 603 1 0 1 1 0 8 0 vmmpekpl 168 7533 0 7481 4 0 4 4 0 8 0 vmmpepl 168 48122 0 46327 96 0 96 96 0 357 11 vmsppl 488 636 0 603 7 1 6 6 0 8 0 rwobjpl 80 15914 0 14997 25 1 24 24 0 8 0 pdppl 4096 1281 0 1206 125 34 91 101 0 8 16 pvpl 32 12924 0 0 106 1 105 105 0 265 0 pmappl 256 636 0 603 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 299 0 41 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(ffffffff834446fb) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83ac7490,1,ffff8000383c29c8) at pool_do_get+0x5df pool_get(ffffffff83ac7490,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff8000fffe7ca8,ffff8000383c2c20,1b4,ffff8000383c2b70) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff8000fffe7ca8,ffff8000383c2c20,ffff8000383c2b70) at sys_shmget+0x195 sys/kern/sysv_shm.c:484 syscall(ffff8000383c2c20) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000383c2c20) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x9fc0d0f5a00, count: -8 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299adff0) 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: 0x7a965842b3b0, count: 12 ddb{1}> trace x86_ipi_db(ffff8000299adff0) 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: 0x7a965842b3b0, count: -3