panic: pool_do_get: shmpl free list modified: page 0xfffffd8069840000; item addr 0xfffffd8069840770; offset 0x40=0x68a527f9 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 234615 72182 32767 0x10 0 1 syz-executor *252838 81539 32767 0x10 0x4000000 0K syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8336bcb4) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8387b540,1,ffff80002a3ef7a8) at pool_do_get+0x5df pool_get(ffffffff8387b540,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a372558,ffff80002a3efa00,2,ffff80002a3ef950) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a372558,ffff80002a3efa00,ffff80002a3ef950) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002a3efa00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3efa00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xad00637df30, 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 0xfffffd8069840000; item addr 0xfffffd8069840770; offset 0x40=0x68a527f9 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8336bcb4) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8387b540,1,ffff80002a3ef7a8) at pool_do_get+0x5df pool_get(ffffffff8387b540,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a372558,ffff80002a3efa00,2,ffff80002a3ef950) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a372558,ffff80002a3efa00,ffff80002a3ef950) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002a3efa00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3efa00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xad00637df30, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a3ef5d0 rbx 0xffffffff8381addf cpu_info_full_primary+0x2ddf rdx 0 rcx 0xffff80002a372558 rax 0xffffffff83819ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x7c5fb1cca4922579 r11 0x3299f477b62aa505 r12 0xffffffff8381abe0 cpu_info_full_primary+0x2be0 r13 0 r14 0 r15 0x1 rip 0xffffffff812c5975 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a3ef5c0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=252838 pid=81539 tcnt=2 stat=onproc flags process=10 proc=4000000 runpri=32, usrpri=54, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a373250,0xffff80002a372038 process=0xffff80003c47f050 user=0xffff80002a3ea000, vmspace=0xfffffd807e397020 estcpu=8, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 20721 150223 4821 32767 2 0x10 syz-executor 83518 113189 77837 32767 2 0x10 syz-executor 96645 285729 89907 32767 2 0x10 syz-executor 97100 375086 6136 32767 2 0x10 syz-executor 72182 234615 65515 32767 7 0x10 syz-executor 72182 74383 65515 32767 2 0x4000010 syz-executor 81539 179648 47522 32767 2 0x10 syz-executor *81539 252838 47522 32767 7 0x4000010 syz-executor 72413 422162 16327 0 2 0x2 syz-executor 18322 414843 33383 32767 3 0x90 nanoslp syz-executor 18322 122890 33383 32767 3 0x4000090 sbwait syz-executor 18322 402882 33383 32767 3 0x4000090 fsleep syz-executor 82965 298340 0 0 3 0x14200 bored sosplice 77837 234127 32240 32767 3 0x90 nanoslp syz-executor 4821 77751 33893 32767 3 0x90 nanoslp syz-executor 89907 202398 27945 32767 3 0x90 nanoslp syz-executor 6136 458438 21143 32767 3 0x90 nanoslp syz-executor 33383 455205 4962 32767 3 0x90 nanoslp syz-executor 65515 508850 19760 32767 3 0x90 nanoslp syz-executor 47522 208984 23709 32767 3 0x90 nanoslp syz-executor 33893 138754 16327 0 3 0x82 wait syz-executor 32240 255346 16327 0 3 0x82 wait syz-executor 27945 505226 16327 0 3 0x82 wait syz-executor 21143 424933 16327 0 3 0x82 wait syz-executor 4962 103933 16327 0 3 0x82 wait syz-executor 19760 513480 16327 0 3 0x82 wait syz-executor 23709 231825 16327 0 3 0x82 wait syz-executor 16327 271383 25623 0 2 0x2 syz-executor 25623 188681 26946 0 3 0x10008a sigsusp ksh 26946 275260 11754 0 3 0x98 kqread sshd-session 11754 310127 77082 0 3 0x92 kqread sshd-session 2320 508741 1 0 3 0x100083 ttyin getty 77082 501297 1 0 3 0x88 kqread sshd 77327 211898 88263 73 3 0x1100090 kqread syslogd 88263 192219 1 0 3 0x100082 sbwait syslogd 57942 380626 1 0 3 0x100080 kqread resolvd 90948 256292 96937 77 3 0x100092 kqread dhcpleased 84312 17307 96937 77 3 0x100092 kqread dhcpleased 96937 370316 1 0 3 0x80 kqread dhcpleased 96280 481593 0 0 3 0x14200 bored smr 62712 503274 0 0 2 0x14200 zerothread 36686 397579 0 0 3 0x14200 aiodoned aiodoned 33691 308680 0 0 3 0x14200 syncer update 35885 114774 0 0 3 0x14200 cleaner cleaner 11039 303687 0 0 3 0x14200 reaper reaper 57934 426461 0 0 3 0x14200 pgdaemon pagedaemon 98318 58824 0 0 3 0x14200 bored viomb 8162 310301 0 0 3 0x40014200 acpi0 acpi0 98744 57959 0 0 3 0x40014200 idle1 84764 71777 0 0 3 0x14200 bored softnet7 83589 126250 0 0 3 0x14200 bored softnet6 56316 3338 0 0 3 0x14200 bored softnet5 72925 339083 0 0 3 0x14200 bored softnet4 56769 316680 0 0 3 0x14200 bored softnet3 50739 483219 0 0 3 0x14200 bored softnet2 54503 216295 0 0 3 0x14200 bored softnet1 83188 377330 0 0 3 0x14200 bored softnet0 80983 353288 0 0 3 0x14200 bored systqmp 30351 142317 0 0 3 0x14200 bored systq 25297 468121 0 0 3 0x14200 tmoslp softclockmp 80754 117270 0 0 3 0x40014200 tmoslp softclock 55766 476250 0 0 3 0x40014200 idle0 1 173078 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 (0xffffffff8387b558) #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:748 #7 Xsyscall+0x128 Process 81539 (syz-executor) thread 0xffff80002a372558 (252838) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8399cf80) #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:748 #2 Xsyscall+0x128 exclusive mutex shmpl r = 0 (0xffffffff8387b558) #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:748 #7 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10191 10954K 10968K 166960K 11272 0 pcb 17 12K 12K 166960K 17 0 rtable 193 5K 6K 166960K 272 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 9 0 counters 66 36K 36K 166960K 68 0 ioctlops 0 0K 2K 166960K 37 0 iov 0 0K 12K 166960K 11 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1334 84K 84K 166960K 1495 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 11 0 VM map 2 1K 1K 166960K 2 0 sem 10 0K 0K 166960K 10 0 dirhash 12 2K 2K 166960K 24 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 24 86K 121K 166960K 433 0 sigio 0 0K 0K 166960K 10 0 proc 59 115K 147K 166960K 505 0 subproc 63 3K 4K 166960K 135 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 32 0 in_multi 88 6K 7K 166960K 105 0 ether_multi 1 0K 0K 166960K 2 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 67 307K 307K 166960K 67 0 exec 0 0K 1K 166960K 438 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 216 167K 195K 166960K 5351 0 UVM aobj 14 3K 4K 166960K 16 0 pinsyscall 45 90K 109K 166960K 1442 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 16 0 NDP 10 0K 2K 166960K 27 0 temp 33 8642K 8707K 166960K 5107 0 kqueue 13 20K 29K 166960K 83 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 64 0 61 1 0 1 1 0 8 0 rtentry 176 99 0 11 5 0 5 5 0 8 0 unpcb 144 343 0 324 4 0 4 4 0 8 3 syncache 336 6 0 6 1 0 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 736 91 0 86 2 0 2 2 0 8 1 arp 128 10 0 1 1 0 1 1 0 8 0 inpcb 328 452 0 443 12 2 10 12 0 8 8 nd6 144 20 0 3 1 0 1 1 0 8 0 kcovpl 48 15 0 8 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 448 0 45 28 0 28 28 0 8 2 art_table 40 449 0 45 5 0 5 5 0 8 0 art_node 32 99 0 20 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 2 1 0 1 1 0 8 1 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 8 0 0 1 0 1 1 0 8 0 shmpl 112 13 0 2 1 0 1 1 0 8 0 pool(0xffffffff8387b540:shmpl): page inconsistency: page 0xfffffd8069840000; 23 on list, 11 missing, 35 items per page dirhash 1024 25 0 8 3 0 3 3 0 8 0 dino2pl 256 1981 0 468 95 0 95 95 0 8 0 ffsino 296 1981 0 468 117 0 117 117 0 8 0 nchpl 144 2515 0 834 63 0 63 63 0 8 0 uvmvnodes 80 2125 0 0 44 0 44 44 0 8 0 vnodes 216 2125 0 0 119 0 119 119 0 8 0 namei 1024 8059 0 8059 1 0 1 1 0 8 1 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 8958 0 8958 4 1 3 3 1 8 3 plimitpl 152 91 0 69 2 0 2 2 0 8 1 sigapl 424 697 0 638 8 0 8 8 0 8 0 knotepl 120 306 0 0 10 0 10 10 0 8 0 kqueuepl 224 237 0 228 5 0 5 5 0 8 4 pipepl 344 154 0 127 4 0 4 4 0 8 0 fdescpl 528 674 0 638 3 0 3 3 0 8 0 filepl 160 3457 0 3258 15 0 15 15 0 8 6 lockfpl 104 75 0 73 1 0 1 1 0 8 0 lockfspl 48 29 0 27 1 0 1 1 0 8 0 sessionpl 144 31 0 16 1 0 1 1 0 8 0 pgrppl 48 55 0 32 1 0 1 1 0 8 0 ucredpl 104 643 0 625 1 0 1 1 0 8 0 zombiepl 144 638 0 638 1 0 1 1 0 8 1 processpl 1232 697 0 638 7 1 6 6 0 8 0 procpl 664 1130 0 1067 7 0 7 7 0 8 0 sosppl 168 3 0 3 1 0 1 1 0 8 1 sockpl 752 863 0 832 16 4 12 16 0 8 8 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl16k 16384 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 124 0 0 16 0 16 16 0 8 0 mcl2k 2048 32 0 0 4 0 4 4 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 266 0 0 17 0 17 17 0 8 0 bufpl 280 3589 0 116 249 0 249 249 0 8 0 anonpl 32 8478 0 0 69 0 69 69 0 246 0 amapchunkpl 152 17273 0 16852 34 1 33 33 0 158 11 amappl16 200 2815 0 2798 17 6 11 14 0 8 8 amappl15 192 4 0 4 1 1 0 1 0 8 0 amappl14 184 109 0 99 1 0 1 1 0 8 0 amappl13 176 65 0 65 1 1 0 1 0 8 0 amappl12 168 1268 0 1237 3 1 2 2 0 8 0 amappl11 160 45 0 35 1 0 1 1 0 8 0 amappl10 152 4 0 4 1 1 0 1 0 8 0 amappl9 144 282 0 282 1 1 0 1 0 8 0 amappl8 136 19 0 17 1 0 1 1 0 8 0 amappl7 128 114 0 104 1 0 1 1 0 8 0 amappl6 120 206 0 203 1 0 1 1 0 8 0 amappl5 112 119 0 113 1 0 1 1 0 8 0 amappl4 104 259 0 245 1 0 1 1 0 8 0 amappl3 96 3001 0 2904 4 0 4 4 0 8 0 amappl2 88 625 0 571 2 0 2 2 0 8 0 amappl1 80 9524 0 8970 15 0 15 15 0 8 1 amappl 88 4649 0 4498 6 0 6 6 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 15 0 2 1 0 1 1 0 8 0 uaddrrnd 24 674 0 638 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 674 0 638 1 0 1 1 0 8 0 vmmpekpl 168 7113 0 7076 3 0 3 3 0 8 0 vmmpepl 168 49322 0 47363 105 0 105 105 0 357 13 vmsppl 488 673 0 638 7 1 6 6 0 8 1 rwobjpl 80 18305 0 15391 62 0 62 62 0 8 1 pdppl 4096 1356 0 1276 109 27 82 96 0 8 2 pvpl 32 15299 0 0 124 0 124 124 0 265 0 pmappl 256 673 0 638 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 287 0 30 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(ffffffff8336bcb4) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff8387b540,1,ffff80002a3ef7a8) at pool_do_get+0x5df pool_get(ffffffff8387b540,1) at pool_get+0x162 sys/kern/subr_pool.c:-1 shmget_allocate_segment(ffff80002a372558,ffff80002a3efa00,2,ffff80002a3ef950) at shmget_allocate_segment+0x1af sys/kern/sysv_shm.c:-1 sys_shmget(ffff80002a372558,ffff80002a3efa00,ffff80002a3ef950) at sys_shmget+0x195 sys/kern/sysv_shm.c:482 syscall(ffff80002a3efa00) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3efa00) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xad00637df30, 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: 0x7c98c06dffe0, 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: 0x7c98c06dffe0, count: -3