panic: pWoAoRNl_IcaNcGh:e _iSPtLem _NmaOgTic L_OcWheERckE:D mObN ufSYpSlC AcpLLu f1re3e7 l-i1s4t 85m9o2di fEieXdI:T i0te 9m adStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND * 52840 43897 0 0x2 0 0 syz-executor.1 286576 74703 0 0x12 0 1 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffdbb80, 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 0xfffffd806d921b00+24 0xe4a9e2acd400496!=0xe4a9eaaa03d1996 ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffdbb80, count: -1 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff8000231951f0 rbx 0 rdx 0xffff800020e6d118 rcx 0 rax 0x39 r8 0xffffffff81b1c4cf kprintf+0x16f r9 0x1 r10 0x25 r11 0xe6894aed5e94dae0 r12 0 r13 0 r14 0xffff800020e6d118 r15 0 rip 0xffffffff810d13f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800023195170 ss 0 savectx+0xb1: movl $0,%gs:0x530 ddb{0}> show proc PROC (syz-executor.1) pid=52840 stat=onproc flags process=2 proc=0 pri=17, usrpri=71, nice=20 forw=0xffffffffffffffff, list=0xffff800020e6c758,0xffff800020ec6298 process=0xffff800020e81720 user=0xffff800023190000, vmspace=0xfffffd807f000a10 estcpu=36, cpticks=1, pctcpu=0.4 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 10244 469891 55363 0 2 0 syz-executor.0 10244 104419 55363 0 2 0x4000000 syz-executor.0 99265 267870 0 0 3 0x14200 bored sosplice *43897 52840 27614 0 7 0x2 syz-executor.1 55363 255732 27614 0 3 0x82 nanosleep syz-executor.0 27614 120518 17640 0 3 0x82 thrsleep syz-fuzzer 27614 306037 17640 0 3 0x4000082 nanosleep syz-fuzzer 27614 97742 17640 0 3 0x4000082 kqread syz-fuzzer 27614 141610 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 494997 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 66190 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 7267 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 173679 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 373701 17640 0 3 0x4000082 thrsleep syz-fuzzer 27614 155817 17640 0 3 0x4000082 thrsleep syz-fuzzer 17640 355791 74703 0 3 0x10008a pause ksh 74703 286576 86359 0 7 0x12 sshd 20183 242170 1 0 3 0x100083 ttyin getty 86359 438804 1 0 3 0x80 select sshd 21946 10758 57549 74 3 0x100092 bpf pflogd 57549 229438 1 0 3 0x80 netio pflogd 33834 37080 40207 73 3 0x100090 kqread syslogd 40207 208817 1 0 3 0x100082 netio syslogd 36999 152132 1 77 3 0x100090 poll dhclient 44091 407479 1 0 3 0x80 poll dhclient 41499 162162 0 0 3 0x14200 bored smr 96177 373517 0 0 2 0x14200 zerothread 88833 166268 0 0 3 0x14200 aiodoned aiodoned 99861 464685 0 0 3 0x14200 syncer update 47970 392342 0 0 3 0x14200 cleaner cleaner 93027 354843 0 0 3 0x14200 reaper reaper 50060 288833 0 0 3 0x14200 pgdaemon pagedaemon 66262 261594 0 0 3 0x14200 bored crynlk 19052 316328 0 0 3 0x14200 bored crypto 60482 185706 0 0 3 0x40014200 acpi0 acpi0 12022 300236 0 0 3 0x40014200 idle1 26549 260503 0 0 3 0x14200 bored softnet 27620 444787 0 0 3 0x14200 bored systqmp 31647 161721 0 0 3 0x14200 bored systq 63554 267371 0 0 3 0x40014200 bored softclock 67660 33885 0 0 3 0x40014200 idle0 1 52272 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &diskp->dk_mtx r = 0 (0xffff80000017ac98) #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 disk_busy+0x21 sys/kern/subr_disk.c:1235 #4 sdstart+0x3dc sys/scsi/sd.c:713 #5 scsi_iopool_run+0x129 scsi_ioh_pending sys/scsi/scsi_base.c:404 [inline] #5 scsi_iopool_run+0x129 sys/scsi/scsi_base.c:420 #6 scsi_xsh_runqueue+0x210 sys/scsi/scsi_base.c:596 #7 scsi_xsh_add+0xc9 sys/scsi/scsi_base.c:535 #8 sdstrategy+0x187 sys/scsi/sd.c:585 #9 spec_strategy+0x74 sys/kern/spec_vnops.c:468 #10 VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:712 #11 bwrite+0x1b9 sys/kern/vfs_bio.c:756 #12 ffs_update+0x2c2 sys/ufs/ffs/ffs_inode.c:113 #13 ffs_truncate+0xc76 #14 ufs_rmdir+0x3af sys/ufs/ufs/ufs_vnops.c:1355 #15 VOP_RMDIR+0xf8 sys/kern/vfs_vops.c:474 #16 dounlinkat+0x14c sys/kern/vfs_syscalls.c:1886 #17 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #17 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #18 Xsyscall+0x128 Process 43897 (syz-executor.1) thread 0xffff800020e6d118 (52840) 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 ufs_dirremove+0x291 #9 ufs_rmdir+0x247 sys/ufs/ufs/ufs_vnops.c:1328 #10 VOP_RMDIR+0xf8 sys/kern/vfs_vops.c:474 #11 dounlinkat+0x14c sys/kern/vfs_syscalls.c:1886 #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 (0xfffffd806dad8a38) #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 (0xfffffd806b357098) #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 exclusive mutex &diskp->dk_mtx r = 0 (0xffff80000017ac98) #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 disk_busy+0x21 sys/kern/subr_disk.c:1235 #4 sdstart+0x3dc sys/scsi/sd.c:713 #5 scsi_iopool_run+0x129 scsi_ioh_pending sys/scsi/scsi_base.c:404 [inline] #5 scsi_iopool_run+0x129 sys/scsi/scsi_base.c:420 #6 scsi_xsh_runqueue+0x210 sys/scsi/scsi_base.c:596 #7 scsi_xsh_add+0xc9 sys/scsi/scsi_base.c:535 #8 sdstrategy+0x187 sys/scsi/sd.c:585 #9 spec_strategy+0x74 sys/kern/spec_vnops.c:468 #10 VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:712 #11 bwrite+0x1b9 sys/kern/vfs_bio.c:756 #12 ffs_update+0x2c2 sys/ufs/ffs/ffs_inode.c:113 #13 ffs_truncate+0xc76 #14 ufs_rmdir+0x3af sys/ufs/ufs/ufs_vnops.c:1355 #15 VOP_RMDIR+0xf8 sys/kern/vfs_vops.c:474 #16 dounlinkat+0x14c sys/kern/vfs_syscalls.c:1886 #17 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #17 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #18 Xsyscall+0x128 Process 74703 (sshd) thread 0xffff800020ed1d50 (286576) 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 9529 6607K 6677K 78643K 10705 0 pcb 13 8K 8K 78643K 40 0 rtable 109 3K 3K 78643K 234 0 ifaddr 75 15K 15K 78643K 78 0 counters 43 33K 33K 78643K 43 0 ioctlops 0 0K 4K 78643K 1473 0 iov 0 0K 16K 78643K 26 0 mount 1 1K 1K 78643K 1 0 vnodes 1217 77K 77K 78643K 1262 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 25 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 134 0 sigio 0 0K 0K 78643K 2 0 proc 61 63K 95K 78643K 454 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 8 0 in_multi 65 3K 3K 78643K 78 0 ether_multi 1 0K 0K 78643K 6 0 mrt 0 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 49 228K 228K 78643K 49 0 exec 0 0K 1K 78643K 221 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 21K 78643K 1351 0 UVM aobj 4 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 26 0 NDP 11 0K 0K 78643K 15 0 temp 90 3036K 3104K 78643K 5095 0 kqueue 3 4K 16K 78643K 11 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 8 0 1 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 31 0 29 1 0 1 1 0 8 0 rtentry 112 50 0 4 2 0 2 2 0 8 0 unpcb 120 53 0 43 1 0 1 1 0 8 0 syncache 264 8 0 8 2 1 1 1 0 8 1 tcpqe 32 389 0 389 1 1 0 1 0 8 0 tcpcb 544 235 0 231 2 0 2 2 0 8 1 inpcb 280 329 0 322 2 0 2 2 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 1 2 0 2 2 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 204 0 2 13 0 13 13 0 8 0 art_table 32 206 0 2 2 0 2 2 0 8 0 art_node 16 49 0 7 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 21 0 11 1 0 1 1 0 8 0 shmpl 112 2 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1575 0 170 89 0 89 89 0 8 0 ffsino 272 1575 0 170 94 0 94 94 0 8 0 nchpl 144 1933 0 319 61 0 61 61 0 8 0 uvmvnodes 72 1639 0 0 30 0 30 30 0 8 0 vnodes 208 1639 0 0 87 0 87 87 0 8 0 namei 1024 5081 0 5081 1 0 1 1 0 8 1 percpumem 16 32 0 0 1 0 1 1 0 8 0 vmpool 560 2 0 2 1 0 1 1 0 8 1 scxspl 192 6163 0 6163 8 1 7 7 0 8 7 plimitpl 152 21 0 13 1 0 1 1 0 8 0 sigapl 424 350 0 318 4 0 4 4 0 8 0 futexpl 56 1945 0 1945 1 0 1 1 0 8 1 knotepl 112 92 0 73 2 0 2 2 0 8 1 kqueuepl 144 30 0 28 1 0 1 1 0 8 0 pipelkpl 48 108 0 98 1 0 1 1 0 8 0 pipepl 120 216 0 197 1 0 1 1 0 8 0 fdescpl 496 334 0 318 3 0 3 3 0 8 0 filepl 152 1884 0 1784 5 0 5 5 0 8 1 lockfpl 104 35 0 34 1 0 1 1 0 8 0 lockfspl 48 15 0 14 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 96 163 0 154 1 0 1 1 0 8 0 zombiepl 144 318 0 318 1 0 1 1 0 8 1 processpl 984 350 0 318 5 0 5 5 0 8 0 procpl 624 609 0 567 4 0 4 4 0 8 0 sosppl 128 2 0 2 1 0 1 1 0 8 1 sockpl 400 414 0 395 4 0 4 4 0 8 2 mcl64k 65536 8 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 214 0 0 26 0 26 26 0 8 0 mtagpl 80 10 0 0 1 0 1 1 0 8 0 mbufpl 256 236 0 0 14 0 14 14 0 8 0 bufpl 280 4482 0 191 307 0 307 307 0 8 0 anonpl 16 44809 0 29568 63 1 62 62 0 124 0 amapchunkpl 152 1665 0 1532 8 0 8 8 0 158 1 amappl16 192 1364 0 534 43 0 43 43 0 8 1 amappl15 184 2 0 1 2 1 1 1 0 8 0 amappl14 176 80 0 74 1 0 1 1 0 8 0 amappl13 168 79 0 75 1 0 1 1 0 8 0 amappl12 160 8 0 4 1 0 1 1 0 8 0 amappl11 152 61 0 45 1 0 1 1 0 8 0 amappl10 144 18 0 14 1 0 1 1 0 8 0 amappl9 136 438 0 436 1 0 1 1 0 8 0 amappl8 128 340 0 328 1 0 1 1 0 8 0 amappl7 120 119 0 108 1 0 1 1 0 8 0 amappl6 112 31 0 25 1 0 1 1 0 8 0 amappl5 104 181 0 166 1 0 1 1 0 8 0 amappl4 96 542 0 514 1 0 1 1 0 8 0 amappl3 88 157 0 150 1 0 1 1 0 8 0 amappl2 80 1765 0 1691 3 1 2 3 0 8 0 amappl1 72 17523 0 17083 25 14 11 20 0 8 1 amappl 80 855 0 813 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 0 1 0 1 1 0 8 0 uaddrrnd 24 336 0 320 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 336 0 320 1 0 1 1 0 8 0 vmmpekpl 168 6633 0 6600 2 0 2 2 0 8 0 vmmpepl 168 47679 0 45717 110 7 103 103 0 357 15 vmsppl 368 335 0 320 2 0 2 2 0 8 0 pdppl 4096 680 0 640 6 0 6 6 0 8 0 pvpl 32 154289 0 135907 153 1 152 152 0 265 3 pmappl 232 335 0 320 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 268 0 3 8 0 8 8 0 8 0