login: panic: pool_do_get: shmpl free list modified: page 0xfffffd8069370000; item addr 0xfffffd8069370938; offset 0x10=0xdeadbe00 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *152353 83030 32767 0x10 0x4000000 0K syz-executor.0 473828 83030 32767 0x10 0x4000000 1 syz-executor.0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x174 sys/kern/subr_prf.c:208 pool_do_get(ffffffff823682b8,1,ffff800020bdd5c4) at pool_do_get+0x4bf sys/kern/subr_pool.c:750 pool_get() at pool_get+0x106 sys/kern/subr_pool.c:587 shmget_allocate_segment(ffff800020b392d8,ffff800020bdd7a8,3,ffff800020bdd790) at shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:409 sys_shmget(ffff800020b392d8,ffff800020bdd7a8,ffff800020bdd790) at sys_shmget+0x13f sys/kern/sysv_shm.c:472 syscall(ffff800020bdd840) at syscall+0x5b8 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bdd840) at syscall+0x5b8 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,fffffffffffffff4,0,4,a7aa42f4010) at Xsyscall+0x128 end of kernel end trace frame: 0xa7d408d64b0, 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 0xfffffd8069370000; item addr 0xfffffd8069370938; offset 0x10=0xdeadbe00 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x174 sys/kern/subr_prf.c:208 pool_do_get(ffffffff823682b8,1,ffff800020bdd5c4) at pool_do_get+0x4bf sys/kern/subr_pool.c:750 pool_get() at pool_get+0x106 sys/kern/subr_pool.c:587 shmget_allocate_segment(ffff800020b392d8,ffff800020bdd7a8,3,ffff800020bdd790) at shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:409 sys_shmget(ffff800020b392d8,ffff800020bdd7a8,ffff800020bdd790) at sys_shmget+0x13f sys/kern/sysv_shm.c:472 syscall(ffff800020bdd840) at syscall+0x5b8 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bdd840) at syscall+0x5b8 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,fffffffffffffff4,0,4,a7aa42f4010) at Xsyscall+0x128 end of kernel end trace frame: 0xa7d408d64b0, count: -8 ddb{0}> show registers rdi 0xffffffff81454e67 db_enter+0x17 rsi 0x3a2c __ALIGN_SIZE+0x2a2c rbp 0xffff800020bdd400 rbx 0xffff800020bdd4b0 rdx 0x3a2d __ALIGN_SIZE+0x2a2d rcx 0xffff80000214b000 rax 0xffff80000214b000 r8 0xffffffff81cae0b3 kprintf+0x183 r9 0x1 r10 0x25 r11 0x23af739172ccb790 r12 0x3000000008 r13 0xffff800020bdd410 r14 0x100 r15 0x1 rip 0xffffffff81454e68 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020bdd3f0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=152353 stat=onproc flags process=10 proc=4000000 pri=75, usrpri=75, nice=20 forw=0xffffffffffffffff, list=0xffff800020b38720,0xffff800020b38028 process=0xffff800020b3ba50 user=0xffff800020bd8000, vmspace=0xfffffd806e936710 estcpu=25, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 83030 340226 16509 32767 2 0x10 syz-executor.0 *83030 152353 16509 32767 7 0x4000010 syz-executor.0 83030 473828 16509 32767 7 0x4000010 syz-executor.0 83030 30505 16509 32767 3 0x4000090 fsleep syz-executor.0 83030 424176 16509 32767 3 0x4000090 fsleep syz-executor.0 83030 70290 16509 32767 3 0x4000090 fsleep syz-executor.0 16509 521080 32430 32767 2 0x490 syz-executor.0 32430 188738 83969 0 3 0x82 wait syz-executor.0 82900 380983 0 0 3 0x14200 bored sosplice 83969 405540 62081 0 3 0x82 thrsleep syz-fuzzer 83969 375050 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 26519 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 349682 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 169326 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 220744 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 177885 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 228363 62081 0 3 0x4000082 thrsleep syz-fuzzer 83969 110296 62081 0 3 0x4000082 kqread syz-fuzzer 83969 2617 62081 0 3 0x4000082 thrsleep syz-fuzzer 62081 145082 65200 0 3 0x10008a pause ksh 65200 18088 86576 0 3 0x92 select sshd 69719 281363 1 0 3 0x100083 ttyin getty 86576 134472 1 0 3 0x80 select sshd 85830 40345 12947 73 3 0x100090 kqread syslogd 12947 114475 1 0 3 0x100082 netio syslogd 1905 343293 1 77 3 0x100090 poll dhclient 38505 75429 1 0 3 0x80 poll dhclient 9553 441626 0 0 3 0x14200 pgzero zerothread 44341 445539 0 0 3 0x14200 aiodoned aiodoned 74929 262463 0 0 3 0x14200 syncer update 83287 115170 0 0 3 0x14200 cleaner cleaner 99090 55629 0 0 3 0x14200 reaper reaper 2886 487545 0 0 3 0x14200 pgdaemon pagedaemon 62950 306457 0 0 3 0x14200 bored crynlk 10229 424593 0 0 3 0x14200 bored crypto 92040 519580 0 0 3 0x40014200 acpi0 acpi0 73688 336443 0 0 3 0x40014200 idle1 51219 464242 0 0 3 0x14200 bored softnet 32629 162179 0 0 3 0x14200 bored systqmp 2151 274365 0 0 3 0x14200 bored systq 40054 335080 0 0 3 0x40014200 bored softclock 87405 332774 0 0 3 0x40014200 idle0 33115 258874 0 0 3 0x14200 bored smr 1 119228 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 (0xffffffff823682c8) locked @ /syzkaller/managers/setuid/kernel/sys/kern/subr_pool.c:583 #0 witness_lock+0x594 sys/kern/subr_witness.c:1201 #1 pool_get+0xda sys/kern/subr_pool.c:584 #2 shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:409 #3 sys_shmget+0x13f sys/kern/sysv_shm.c:472 #4 syscall+0x5b8 mi_syscall sys/sys/syscall_mi.h:99 [inline] #4 syscall+0x5b8 sys/arch/amd64/amd64/trap.c:574 #5 Xsyscall+0x128 Process 83030 (syz-executor.0) thread 0xffff800020b392d8 (152353) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82347588) locked @ /syzkaller/managers/setuid/kernel/sys/sys/syscall_mi.h:90 #0 witness_lock+0x594 sys/kern/subr_witness.c:1201 #1 syscall+0x48b mi_syscall sys/sys/syscall_mi.h:91 [inline] #1 syscall+0x48b sys/arch/amd64/amd64/trap.c:574 #2 Xsyscall+0x128 exclusive mutex shmpl r = 0 (0xffffffff823682c8) locked @ /syzkaller/managers/setuid/kernel/sys/kern/subr_pool.c:583 #0 witness_lock+0x594 sys/kern/subr_witness.c:1201 #1 pool_get+0xda sys/kern/subr_pool.c:584 #2 shmget_allocate_segment+0x15e sys/kern/sysv_shm.c:409 #3 sys_shmget+0x13f sys/kern/sysv_shm.c:472 #4 syscall+0x5b8 mi_syscall sys/sys/syscall_mi.h:99 [inline] #4 syscall+0x5b8 sys/arch/amd64/amd64/trap.c:574 #5 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9454 6318K 6321K 78643K 10671 0 0 pcb 23 9K 11K 78643K 412 0 0 rtable 79 2K 3K 78643K 981 0 0 ifaddr 29 9K 10K 78643K 188 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 48 0 0 iov 0 0K 16K 78643K 48 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1200 75K 75K 78643K 1791 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 11 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 1K 78643K 89 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 5 13K 33K 78643K 758 0 0 sigio 0 0K 0K 78643K 2 0 0 proc 41 38K 58K 78643K 877 0 0 subproc 34 34817K 69634K 78643K 918 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 102 0 0 in_multi 22 1K 2K 78643K 320 0 0 ether_multi 1 0K 0K 78643K 2 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 54 238K 238K 78643K 54 0 0 exec 0 0K 1K 78643K 323 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 86 12K 29K 78643K 3138 0 0 UVM aobj 41 2K 2K 78643K 47 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 69 0 0 NDP 4 0K 0K 78643K 84 0 0 temp 96 2376K 2447K 78643K 6181 0 0 kqueue 0 0K 0K 78643K 11 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 29 0 26 1 0 1 1 0 8 0 inpcbpl 280 399 0 389 1 0 1 1 0 8 0 plimitpl 152 99 0 92 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 266 0 235 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpcb 544 126 0 122 1 0 1 1 0 8 0 nd6 48 54 0 52 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1226 0 1079 12 0 12 12 0 8 0 art_table 32 1227 0 1079 2 0 2 2 0 8 0 art_node 16 265 0 237 1 0 1 1 0 8 0 sysvmsgpl 40 7 0 7 1 1 0 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 83 0 73 1 0 1 1 0 8 0 shmpl 112 45 0 6 2 0 2 2 0 8 0 shmpl: pool(0xffffffff823682b8:shmpl): page inconsistency: page 0xfffffd8069370000; item ordinal 0; addr 0x13cf7287fd20864a dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2276 0 837 47 0 47 47 0 8 0 ffsino 272 2276 0 837 97 0 97 97 0 8 0 nchpl 144 3484 0 1877 61 1 60 61 0 8 0 uvmvnodes 72 2744 0 0 50 0 50 50 0 8 0 vnodes 200 2744 0 0 145 0 145 145 0 8 0 namei 1024 11089 0 11089 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 9829 0 9829 9 8 1 6 0 8 1 sigapl 432 853 0 840 3 1 2 3 0 8 0 futexpl 56 6658 0 6655 1 0 1 1 0 8 0 knotepl 112 761 0 748 1 0 1 1 0 8 0 kqueuepl 104 223 0 220 1 0 1 1 0 8 0 pipepl 112 818 0 805 4 3 1 2 0 8 0 fdescpl 488 854 0 840 3 0 3 3 0 8 1 filepl 152 5779 0 5701 10 5 5 7 0 8 1 lockfpl 104 174 0 173 4 3 1 1 0 8 0 lockfspl 32 305 0 304 4 3 1 1 0 8 0 sessionpl 112 42 0 33 1 0 1 1 0 8 0 pgrppl 48 53 0 44 1 0 1 1 0 8 0 ucredpl 96 1534 0 1526 1 0 1 1 0 8 0 zombiepl 144 840 0 840 2 1 1 1 0 8 1 processpl 840 870 0 840 4 0 4 4 0 8 0 procpl 600 2088 0 2044 4 0 4 4 0 8 0 srpgc 64 154 0 154 2 1 1 1 0 8 1 sosppl 128 13 0 13 4 4 0 1 0 8 0 sockpl 384 806 0 786 5 2 3 4 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 6 0 0 1 0 1 1 0 8 0 mcl9k 9216 4 0 0 1 0 1 1 0 8 0 mcl8k 8192 6 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 122 0 0 14 2 12 14 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 157 0 0 9 0 9 9 0 8 0 bufpl 256 7024 0 1122 369 0 369 369 0 8 0 anonpl 16 111322 0 105510 52 19 33 41 0 125 5 amapchunkpl 152 6451 0 6361 24 15 9 11 0 158 5 amappl16 192 3845 0 3485 38 18 20 30 0 8 1 amappl15 184 91 0 87 1 0 1 1 0 8 0 amappl14 176 196 0 191 2 1 1 1 0 8 0 amappl13 168 160 0 156 1 0 1 1 0 8 0 amappl12 160 188 0 183 1 0 1 1 0 8 0 amappl11 152 57 0 46 1 0 1 1 0 8 0 amappl10 144 161 0 156 1 0 1 1 0 8 0 amappl9 136 805 0 803 1 0 1 1 0 8 0 amappl8 128 420 0 398 1 0 1 1 0 8 0 amappl7 120 135 0 128 1 0 1 1 0 8 0 amappl6 112 76 0 70 1 0 1 1 0 8 0 amappl5 104 237 0 226 1 0 1 1 0 8 0 amappl4 96 998 0 972 2 1 1 2 0 8 0 amappl3 88 317 0 311 1 0 1 1 0 8 0 amappl2 80 5585 0 5534 2 0 2 2 0 8 0 amappl1 72 29016 0 28581 23 13 10 19 0 8 0 amappl 72 2486 0 2450 1 0 1 1 0 75 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 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 46 0 6 1 0 1 1 0 8 0 uaddrrnd 24 854 0 840 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 854 0 840 1 0 1 1 0 8 0 vmmpekpl 168 10990 0 10965 2 0 2 2 0 8 0 vmmpepl 168 105649 0 104319 106 31 75 76 0 357 12 vmsppl 360 853 0 840 2 0 2 2 0 8 0 pdppl 4096 1716 0 1680 6 0 6 6 0 8 1 pvpl 32 317549 0 308067 147 50 97 113 0 265 15 pmappl 224 853 0 840 3 1 2 2 0 8 1 extentpl 40 39 0 25 1 0 1 1 0 8 0 phpool 112 520 0 5 15 0 15 15 0 8 0