panic: pool_cache_item_mWaAgRiNcIN_Gc:h ecSPkL: NOmTb uLfOWpEl REcDp OuN f SrYeSe CAliLLs t1 m3o6d i-fi35e7d:6 0i EtXeImT ad0dr 9 0 xStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND *418769 62549 0 0x2 0 0 syz-executor.0 117442 2126 0 0x12 0 1 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7fffff74c0, count: 14 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_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd807e94e200+16 0x0!=0xa29eb1bbfce413d6 ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7fffff74c0, count: -1 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff800020f6bc20 rbx 0 rdx 0xffff800020e6dd48 rcx 0 rax 0x38 r8 0xffffffff81b1c4cf kprintf+0x16f r9 0x1 r10 0x25 r11 0x87754b05314e49b1 r12 0 r13 0 r14 0xffff800020e6dd48 r15 0 rip 0xffffffff810d13f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800020f6bba0 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{0}> show proc PROC (syz-executor.0) pid=418769 stat=onproc flags process=2 proc=0 pri=17, usrpri=83, nice=20 forw=0xffffffffffffffff, list=0xffff800020e6cea8,0xffff800020e93af8 process=0xffff800020e81348 user=0xffff800020f66000, vmspace=0xfffffd807f000170 estcpu=33, cpticks=2, pctcpu=0.7 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 42023 119236 33199 0 2 0x2 syz-executor.1 *62549 418769 33199 0 7 0x2 syz-executor.0 33199 235573 91866 0 3 0x82 thrsleep syz-fuzzer 33199 42494 91866 0 3 0x4000082 nanosleep syz-fuzzer 33199 381421 91866 0 3 0x4000082 thrsleep syz-fuzzer 33199 237513 91866 0 3 0x4000082 thrsleep syz-fuzzer 33199 191531 91866 0 3 0x4000082 nanosleep syz-fuzzer 33199 222401 91866 0 3 0x4000082 thrsleep syz-fuzzer 33199 383238 91866 0 3 0x4000082 thrsleep syz-fuzzer 33199 354201 91866 0 3 0x4000082 thrsleep syz-fuzzer 33199 303293 91866 0 3 0x4000082 kqread syz-fuzzer 33199 414943 91866 0 3 0x4000082 thrsleep syz-fuzzer 91866 417166 2126 0 3 0x10008a pause ksh 2126 117442 41906 0 7 0x12 sshd 66782 309388 1 0 3 0x100083 ttyin getty 41906 408906 1 0 3 0x80 select sshd 60912 522457 45654 74 3 0x100092 bpf pflogd 45654 142347 1 0 3 0x80 netio pflogd 53945 321592 23510 73 3 0x100090 kqread syslogd 23510 413632 1 0 3 0x100082 netio syslogd 44695 274205 1 77 3 0x100090 poll dhclient 92314 268440 1 0 3 0x80 poll dhclient 55230 175575 0 0 3 0x14200 bored smr 89257 105074 0 0 3 0x14200 pgzero zerothread 49278 247504 0 0 3 0x14200 aiodoned aiodoned 73571 122563 0 0 3 0x14200 syncer update 30325 151324 0 0 3 0x14200 cleaner cleaner 91518 446463 0 0 3 0x14200 reaper reaper 68917 38154 0 0 3 0x14200 pgdaemon pagedaemon 84644 83450 0 0 3 0x14200 bored crynlk 7328 333461 0 0 3 0x14200 bored crypto 16321 417193 0 0 3 0x40014200 acpi0 acpi0 65990 434178 0 0 3 0x40014200 idle1 44942 318573 0 0 2 0x14200 softnet 24500 220322 0 0 3 0x14200 bored systqmp 48726 187130 0 0 3 0x14200 bored systq 81080 7769 0 0 3 0x40014200 bored softclock 6464 315426 0 0 3 0x40014200 idle0 1 404902 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &iopl->mtx r = 0 (0xffff800000038170) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 scsi_xsh_runqueue+0x37 scsi_pending_start sys/scsi/scsi_base.c:214 [inline] #3 scsi_xsh_runqueue+0x37 sys/scsi/scsi_base.c:576 #4 scsi_xsh_add+0xc9 sys/scsi/scsi_base.c:535 #5 sdstrategy+0x187 sys/scsi/sd.c:585 #6 spec_strategy+0x74 sys/kern/spec_vnops.c:468 #7 ufs_strategy+0x17c #8 VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:712 #9 bwrite+0x1b9 sys/kern/vfs_bio.c:756 #10 VOP_BWRITE+0x4a sys/kern/vfs_vops.c:724 #11 ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1248 #12 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #13 domkdirat+0x121 sys/kern/vfs_syscalls.c:3051 #14 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #14 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #15 Xsyscall+0x128 Process 42023 (syz-executor.1) thread 0xffff800020e93ae8 (119236) exclusive rrwlock inode r = 0 (0xfffffd806495b920) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:575 #5 vget+0x1c8 sys/kern/vfs_subr.c:671 #6 ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1329 #8 ufs_lookup+0x14b7 sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:90 #10 vfs_lookup+0x7a6 sys/kern/vfs_lookup.c:568 #11 namei+0x63c sys/kern/vfs_lookup.c:249 #12 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1853 #13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806b3721a8) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:575 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1853 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #9 Xsyscall+0x128 Process 62549 (syz-executor.0) thread 0xffff800020e6dd48 (418769) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82677920) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 #2 mi_switch+0x392 sys/kern/sched_bsd.c:435 #3 sleep_finish+0x113 sys/kern/kern_synch.c:418 #4 sleep_finish_all+0x32 sleep_finish_timeout sys/kern/kern_synch.c:447 [inline] #4 sleep_finish_all+0x32 sys/kern/kern_synch.c:393 #5 tsleep+0x1cc sys/kern/kern_synch.c:155 #6 biowait+0xa6 sys/kern/vfs_bio.c:1255 #7 bwrite+0x1e4 sys/kern/vfs_bio.c:765 #8 ffs_update+0x2c2 sys/ufs/ffs/ffs_inode.c:113 #9 ufs_mkdir+0x665 sys/ufs/ufs/ufs_vnops.c:1232 #10 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #11 domkdirat+0x121 sys/kern/vfs_syscalls.c:3051 #12 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #12 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #13 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806495b1b0) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 ufs_ihashins+0x45 sys/ufs/ufs/ufs_ihash.c:140 #4 ffs_vget+0x13e sys/ufs/ffs/ffs_vfsops.c:1358 #5 ffs_inode_alloc+0x1cf sys/ufs/ffs/ffs_alloc.c:392 #6 ufs_mkdir+0xf4 sys/ufs/ufs/ufs_vnops.c:1162 #7 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #8 domkdirat+0x121 sys/kern/vfs_syscalls.c:3051 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #10 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806b3722b8) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:311 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:575 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 domkdirat+0x75 sys/kern/vfs_syscalls.c:3036 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #9 Xsyscall+0x128 exclusive mutex &iopl->mtx r = 0 (0xffff800000038170) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 scsi_xsh_runqueue+0x37 scsi_pending_start sys/scsi/scsi_base.c:214 [inline] #3 scsi_xsh_runqueue+0x37 sys/scsi/scsi_base.c:576 #4 scsi_xsh_add+0xc9 sys/scsi/scsi_base.c:535 #5 sdstrategy+0x187 sys/scsi/sd.c:585 #6 spec_strategy+0x74 sys/kern/spec_vnops.c:468 #7 ufs_strategy+0x17c #8 VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:712 #9 bwrite+0x1b9 sys/kern/vfs_bio.c:756 #10 VOP_BWRITE+0x4a sys/kern/vfs_vops.c:724 #11 ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1248 #12 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #13 domkdirat+0x121 sys/kern/vfs_syscalls.c:3051 #14 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #14 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #15 Xsyscall+0x128 Process 2126 (sshd) thread 0xffff800020ed1390 (117442) exclusive rwlock netlock r = 0 (0xffffffff825363f8) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x559 sys/kern/uipc_socket.c:537 #3 dofilewritev+0x1b6 sys/kern/sys_generic.c:365 #4 sys_write+0x83 sys/kern/sys_generic.c:285 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9532 6671K 7060K 78643K 11053 0 pcb 13 8K 8K 78643K 39 0 rtable 89 2K 3K 78643K 238 0 ifaddr 68 13K 13K 78643K 91 0 counters 43 33K 34K 78643K 49 0 ioctlops 0 0K 4K 78643K 1473 0 iov 0 0K 32K 78643K 11 0 mount 1 1K 1K 78643K 1 0 vnodes 1224 77K 77K 78643K 1344 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 9 0K 1K 78643K 12 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 4 9K 25K 78643K 110 0 sigio 0 0K 0K 78643K 2 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 4 0 in_multi 37 2K 2K 78643K 47 0 ether_multi 1 0K 0K 78643K 5 0 mrt 0 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 85 387K 387K 78643K 85 0 exec 0 0K 1K 78643K 214 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 97 21K 22K 78643K 1263 0 UVM aobj 6 2K 2K 78643K 6 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 16 0 NDP 11 0K 0K 78643K 18 0 temp 91 3037K 3105K 78643K 2846 0 kqueue 3 4K 18K 78643K 42 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 23 0 21 1 0 1 1 0 8 0 rtentry 112 48 0 12 2 0 2 2 0 8 0 unpcb 120 61 0 51 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 638 0 638 1 1 0 1 0 8 0 tcpcb 544 40 0 36 1 0 1 1 0 8 0 inpcb 280 128 0 121 1 0 1 1 0 8 0 rttmr 72 1 0 1 1 0 1 1 0 8 1 nd6 48 6 0 0 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 16 0 1 1 0 1 1 0 8 0 pfstkey 112 16 0 1 1 0 1 1 0 8 0 pfstate 328 16 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 256 200 0 47 13 0 13 13 0 8 1 art_table 32 201 0 47 2 0 2 2 0 8 0 art_node 16 47 0 17 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 0 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 7 0 0 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1544 0 135 89 0 89 89 0 8 0 ffsino 272 1544 0 135 95 0 95 95 0 8 0 nchpl 144 1869 0 256 61 0 61 61 0 8 0 uvmvnodes 72 1691 0 0 31 0 31 31 0 8 0 vnodes 208 1691 0 0 89 0 89 89 0 8 0 namei 1024 5243 0 5243 1 0 1 1 0 8 1 percpumem 16 35 0 3 1 0 1 1 0 8 0 scxspl 192 5685 0 5685 8 3 5 7 0 8 5 plimitpl 152 21 0 13 1 0 1 1 0 8 0 sigapl 424 325 0 295 4 0 4 4 0 8 0 futexpl 56 1535 0 1535 1 0 1 1 0 8 1 knotepl 112 113 0 94 1 0 1 1 0 8 0 kqueuepl 144 82 0 80 1 0 1 1 0 8 0 pipelkpl 48 80 0 70 1 0 1 1 0 8 0 pipepl 120 160 0 141 1 0 1 1 0 8 0 fdescpl 496 310 0 295 3 0 3 3 0 8 0 filepl 152 1906 0 1806 6 0 6 6 0 8 2 lockfpl 104 18 0 17 1 0 1 1 0 8 0 lockfspl 48 9 0 8 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 96 300 0 290 1 0 1 1 0 8 0 zombiepl 144 295 0 295 2 1 1 1 0 8 1 processpl 984 325 0 295 6 1 5 5 0 8 1 procpl 624 514 0 475 4 0 4 4 0 8 0 sockpl 400 212 0 193 4 1 3 3 0 8 1 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 182 0 0 22 0 22 22 0 8 0 mtagpl 80 10 0 0 1 0 1 1 0 8 0 mbufpl 256 224 0 0 13 0 13 13 0 8 0 bufpl 280 4305 0 190 294 0 294 294 0 8 0 anonpl 16 41641 0 27348 60 1 59 59 0 124 0 amapchunkpl 152 1461 0 1310 8 0 8 8 0 158 0 amappl16 192 1183 0 414 39 0 39 39 0 8 0 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 98 0 93 1 0 1 1 0 8 0 amappl13 168 68 0 64 1 0 1 1 0 8 0 amappl12 160 11 0 7 1 0 1 1 0 8 0 amappl11 152 54 0 39 1 0 1 1 0 8 0 amappl10 144 15 0 12 1 0 1 1 0 8 0 amappl9 136 394 0 392 1 0 1 1 0 8 0 amappl8 128 296 0 283 1 0 1 1 0 8 0 amappl7 120 119 0 108 1 0 1 1 0 8 0 amappl6 112 24 0 21 1 0 1 1 0 8 0 amappl5 104 169 0 154 1 0 1 1 0 8 0 amappl4 96 532 0 504 1 0 1 1 0 8 0 amappl3 88 182 0 176 1 0 1 1 0 8 0 amappl2 80 1492 0 1432 3 1 2 3 0 8 0 amappl1 72 16808 0 16381 25 15 10 20 0 8 0 amappl 80 764 0 720 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 5 0 0 1 0 1 1 0 8 0 uaddrrnd 24 310 0 295 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 310 0 295 1 0 1 1 0 8 0 vmmpekpl 168 6371 0 6343 2 0 2 2 0 8 0 vmmpepl 168 44620 0 42833 114 11 103 107 0 357 18 vmsppl 368 309 0 295 2 0 2 2 0 8 0 pdppl 4096 628 0 590 6 0 6 6 0 8 0 pvpl 32 149479 0 132112 150 2 148 148 0 265 4 pmappl 232 309 0 295 2 1 1 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 260 0 4 8 0 8 8 0 8 0