panic: pool_do_get: shmpl free list modified: page 0xfffffd8062243000; item addr 0xfffffd8062243e00; offset 0x24=0x100ca Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *268839 71398 0 0 0x4000000 0K syz-executor.1 65752 72476 0 0 0x4000000 1 syz-executor.0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8220d3b4) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_get(ffffffff8263a120,1,ffff800023bb5a58) at pool_do_get+0x472 sys/kern/subr_pool.c:744 pool_get(ffffffff8263a120,1) at pool_get+0xeb sys/kern/subr_pool.c:581 shmget_allocate_segment(ffff800020ac1160,ffff800023bb5be8,169,ffff800023bb5c30) at shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:405 sys_shmget(ffff800020ac1160,ffff800023bb5be8,ffff800023bb5c30) at sys_shmget+0x13f sys/kern/sysv_shm.c:468 syscall(ffff800023bb5cb0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800023bb5cb0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2474dc4eb90, 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 pool_do_get: shmpl free list modified: page 0xfffffd8062243000; item addr 0xfffffd8062243e00; offset 0x24=0x100ca ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8220d3b4) at panic+0x15c sys/kern/subr_prf.c:207 pool_do_get(ffffffff8263a120,1,ffff800023bb5a58) at pool_do_get+0x472 sys/kern/subr_pool.c:744 pool_get(ffffffff8263a120,1) at pool_get+0xeb sys/kern/subr_pool.c:581 shmget_allocate_segment(ffff800020ac1160,ffff800023bb5be8,169,ffff800023bb5c30) at shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:405 sys_shmget(ffff800020ac1160,ffff800023bb5be8,ffff800023bb5c30) at sys_shmget+0x13f sys/kern/sysv_shm.c:468 syscall(ffff800023bb5cb0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800023bb5cb0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2474dc4eb90, count: -8 ddb{0}> show registers rdi 0xffffffff813ee2e7 db_enter+0x17 rsi 0x36b9 __ALIGN_SIZE+0x26b9 rbp 0xffff800023bb58a0 rbx 0xffff800023bb5950 rdx 0x36ba __ALIGN_SIZE+0x26ba rcx 0xffff800021b8c000 rax 0xffff800021b8c000 r8 0xffffffff81cd657f kprintf+0x16f r9 0x1 r10 0x25 r11 0x8c97342d0e3a9c22 r12 0x3000000008 r13 0xffff800023bb58b0 r14 0x100 r15 0x1 rip 0xffffffff813ee2e8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800023bb5890 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.1) pid=268839 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020ac0290,0xffffffff82617120 process=0xffff800020aec000 user=0xffff800023bb0000, vmspace=0xfffffd807f0085c0 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 71398 509819 65132 0 2 0 syz-executor.1 *71398 268839 65132 0 7 0x4000000 syz-executor.1 72476 128119 45782 0 2 0 syz-executor.0 72476 65752 45782 0 7 0x4000000 syz-executor.0 89994 172040 0 0 3 0x14200 bored sosplice 65132 123358 1881 0 2 0x482 syz-executor.1 45782 320851 1881 0 2 0x482 syz-executor.0 1881 498994 73496 0 3 0x82 thrsleep syz-fuzzer 1881 372620 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 86811 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 436956 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 195214 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 303069 73496 0 3 0x4000082 kqread syz-fuzzer 1881 2535 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 43419 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 358905 73496 0 3 0x4000082 thrsleep syz-fuzzer 1881 117441 73496 0 3 0x4000082 thrsleep syz-fuzzer 73496 24559 18782 0 3 0x10008a pause ksh 18782 508227 80466 0 3 0x92 select sshd 42847 240373 1 0 3 0x100083 ttyin getty 80466 152580 1 0 3 0x80 select sshd 84252 82997 74163 74 3 0x100092 bpf pflogd 74163 402267 1 0 3 0x80 netio pflogd 24673 267324 45654 73 3 0x100090 kqread syslogd 45654 355047 1 0 3 0x100082 netio syslogd 81830 76402 1 77 3 0x100090 poll dhclient 80512 165627 1 0 3 0x80 poll dhclient 5104 28314 0 0 2 0x14200 zerothread 31241 107290 0 0 3 0x14200 aiodoned aiodoned 77470 225797 0 0 3 0x14200 syncer update 58164 26889 0 0 3 0x14200 cleaner cleaner 67427 324336 0 0 3 0x14200 reaper reaper 60635 441304 0 0 3 0x14200 pgdaemon pagedaemon 659 280694 0 0 3 0x14200 bored crynlk 45312 382641 0 0 3 0x14200 bored crypto 64835 178163 0 0 3 0x40014200 acpi0 acpi0 28669 316897 0 0 3 0x40014200 idle1 55458 345732 0 0 2 0x14200 softnet 32957 217014 0 0 3 0x14200 bored systqmp 80665 387496 0 0 3 0x14200 bored systq 89299 113776 0 0 3 0x40014200 bored softclock 12293 441895 0 0 3 0x40014200 idle0 85647 325655 0 0 3 0x14200 bored smr 1 277478 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 (0xffffffff8263a130) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pool_get+0xbf sys/kern/subr_pool.c:578 #4 shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:405 #5 sys_shmget+0x13f sys/kern/sysv_shm.c:468 #6 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #6 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #7 Xsyscall+0x128 CPU 1: exclusive mutex mbufpl r = 0 (0xffffffff8263a8b8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 pool_cache_get+0xa3 pl_enter_try sys/kern/subr_pool.c:109 [inline] #2 pool_cache_get+0xa3 pool_list_enter sys/kern/subr_pool.c:1797 [inline] #2 pool_cache_get+0xa3 pool_cache_list_alloc sys/kern/subr_pool.c:1814 [inline] #2 pool_cache_get+0xa3 sys/kern/subr_pool.c:1887 #3 pool_get+0x91 sys/kern/subr_pool.c:572 #4 m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 #5 ip_fragment+0x13a sys/netinet/ip_output.c:682 #6 ip_output+0xfc1 sys/netinet/ip_output.c:501 #7 rip_output+0x252 sys/netinet/raw_ip.c:289 #8 rip_usrreq+0x46a sys/netinet/raw_ip.c:538 #9 sosend+0x645 sys/kern/uipc_socket.c:524 #10 sendit+0x52b sys/kern/uipc_syscalls.c:662 #11 sys_sendto+0x80 sys/kern/uipc_syscalls.c:527 #12 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #12 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #13 Xsyscall+0x128 Process 71398 (syz-executor.1) thread 0xffff800020ac1160 (268839) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82651ec8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 syscall+0x400 mi_syscall sys/sys/syscall_mi.h:83 [inline] #1 syscall+0x400 sys/arch/amd64/amd64/trap.c:555 #2 Xsyscall+0x128 exclusive mutex shmpl r = 0 (0xffffffff8263a130) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pool_get+0xbf sys/kern/subr_pool.c:578 #4 shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:405 #5 sys_shmget+0x13f sys/kern/sysv_shm.c:468 #6 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #6 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #7 Xsyscall+0x128 Process 72476 (syz-executor.0) thread 0xffff800020ac0290 (65752) exclusive rwlock netlock r = 0 (0xffffffff824c24a8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x51b sys/kern/uipc_socket.c:512 #3 sendit+0x52b sys/kern/uipc_syscalls.c:662 #4 sys_sendto+0x80 sys/kern/uipc_syscalls.c:527 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #6 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9494 6469K 6982K 78643K 10731 0 pcb 13 8K 8K 78643K 25 0 rtable 108 3K 4K 78643K 229 0 ifaddr 54 12K 12K 78643K 60 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1469 0 iov 0 0K 2K 78643K 2 0 mount 1 1K 1K 78643K 1 0 vnodes 1232 77K 77K 78643K 1272 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 4 0 VM map 2 1K 1K 78643K 2 0 sem 10 0K 0K 78643K 14 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 6 17K 25K 78643K 70 0 proc 59 63K 83K 78643K 447 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 12 0 in_multi 29 1K 2K 78643K 41 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 42 185K 185K 78643K 42 0 exec 0 0K 1K 78643K 211 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 117 22K 26K 78643K 1164 0 UVM aobj 2 2K 2K 78643K 4 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 2 0 NDP 8 0K 0K 78643K 13 0 temp 83 3009K 3073K 78643K 6739 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 25 0 23 1 0 1 1 0 8 0 rtentry 112 53 0 9 2 0 2 2 0 8 0 unpcb 120 43 0 32 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 256 0 256 1 0 1 1 0 8 1 tcpcb 544 40 0 36 1 0 1 1 0 8 0 inpcb 280 112 0 104 2 0 2 2 0 8 1 nd6 48 5 0 2 1 0 1 1 0 8 0 ppxss 1128 1 0 0 1 0 1 1 0 8 0 pffrag 232 3 0 2 1 0 1 1 0 482 0 pffrnode 88 3 0 2 1 0 1 1 0 8 0 pffrent 40 106 0 90 1 0 1 1 0 8 0 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 20 0 0 1 0 1 1 0 8 0 pfstkey 112 20 0 0 1 0 1 1 0 8 0 pfstate 328 20 0 0 2 0 2 2 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 249 0 45 14 0 14 14 0 8 0 art_table 32 250 0 45 2 0 2 2 0 8 0 art_node 16 52 0 11 1 0 1 1 0 8 0 sysvmsgpl 40 4 0 3 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 8 0 0 1 0 1 1 0 8 0 shmpl 112 2 0 2 1 0 1 1 0 8 1 pool(0xffffffff8263a120:shmpl): page inconsistency: page 0xfffffd8062243000; 34 on list, 0 missing, 35 items per page dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1483 0 73 46 0 46 46 0 8 0 ffsino 272 1483 0 73 95 0 95 95 0 8 0 nchpl 144 1771 0 149 61 0 61 61 0 8 0 uvmvnodes 72 1568 0 0 29 0 29 29 0 8 0 vnodes 208 1568 0 0 83 0 83 83 0 8 0 namei 1024 4705 0 4705 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 5224 0 5224 2 1 1 2 0 8 1 plimitpl 152 17 0 9 1 0 1 1 0 8 0 sigapl 432 269 0 253 3 0 3 3 0 8 1 futexpl 56 907 0 907 1 0 1 1 0 8 1 knotepl 112 57 0 38 1 0 1 1 0 8 0 kqueuepl 104 10 0 8 1 0 1 1 0 8 0 pipepl 160 178 0 157 1 0 1 1 0 8 0 fdescpl 488 270 0 253 3 0 3 3 0 8 0 filepl 152 1563 0 1450 5 0 5 5 0 8 0 lockfpl 104 17 0 16 1 0 1 1 0 8 0 lockfspl 48 6 0 5 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 111 0 102 1 0 1 1 0 8 0 zombiepl 144 253 0 253 1 0 1 1 0 8 1 processpl 896 286 0 253 4 0 4 4 0 8 0 procpl 632 386 0 342 5 0 5 5 0 8 1 sosppl 128 3 0 3 1 0 1 1 0 8 1 sockpl 384 180 0 159 4 0 4 4 0 8 1 mcl64k 65536 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 171 0 0 21 0 21 21 0 8 0 mtagpl 80 4 0 0 1 0 1 1 0 8 0 mbufpl 256 378 0 0 24 0 24 24 0 8 0 bufpl 280 6330 0 1344 357 0 357 357 0 8 0 anonpl 16 48917 0 29820 90 1 89 89 0 125 12 amapchunkpl 152 1405 0 1245 8 0 8 8 0 158 1 amappl16 192 1502 0 454 62 4 58 62 0 8 5 amappl15 184 77 0 72 1 0 1 1 0 8 0 amappl14 176 31 0 30 1 0 1 1 0 8 0 amappl13 168 20 0 17 1 0 1 1 0 8 0 amappl12 160 2 0 1 2 1 1 1 0 8 0 amappl11 152 59 0 44 1 0 1 1 0 8 0 amappl10 144 16 0 12 1 0 1 1 0 8 0 amappl9 136 605 0 601 1 0 1 1 0 8 0 amappl8 128 125 0 101 1 0 1 1 0 8 0 amappl7 120 111 0 98 1 0 1 1 0 8 0 amappl6 112 57 0 50 1 0 1 1 0 8 0 amappl5 104 129 0 115 1 0 1 1 0 8 0 amappl4 96 521 0 488 2 1 1 2 0 8 0 amappl3 88 118 0 111 1 0 1 1 0 8 0 amappl2 80 1298 0 1212 3 1 2 3 0 8 0 amappl1 72 16281 0 15822 25 11 14 20 0 8 4 amappl 80 638 0 590 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 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 64 3 0 2 1 0 1 1 0 8 0 uaddrrnd 24 270 0 253 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 270 0 253 1 0 1 1 0 8 0 vmmpekpl 168 6046 0 6013 2 0 2 2 0 8 0 vmmpepl 168 42468 0 40144 137 5 132 132 0 357 30 vmsppl 368 269 0 253 2 0 2 2 0 8 0 pdppl 4096 547 0 506 6 0 6 6 0 8 0 pvpl 32 159731 0 137376 213 0 213 213 0 265 32 pmappl 232 269 0 253 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 175 0 3 5 0 5 5 0 8 0