panic: pool_cache_iWtAeRmN_INmaGg:i cS_PcLh eNcOkT: mLbOuWfEpRl cEpuD fOrNe eSY lSCiAsLt Lm o1d37i fi-e2d3:4 3i0t4e mE XadITd r0 0x9f ffStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND * 1958 15718 0 0x2 0 0 syz-executor.0 168794 11885 0 0x12 0 1 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc6cb0, 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 0xfffffd8061577e00+16 0x0!=0x92facf967046394d ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc6cb0, count: -1 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff800020b21470 rbx 0 rdx 0xffff800020ab09f8 rcx 0 rax 0x39 r8 0xffffffff8101132f kprintf+0x16f r9 0x1 r10 0x25 r11 0x96b7a053ad01b73 r12 0 r13 0 r14 0xffff800020ab09f8 r15 0 rip 0xffffffff817993f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800020b213f0 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{0}> show proc PROC (syz-executor.0) pid=1958 stat=onproc flags process=2 proc=0 pri=77, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffff800020a5e4f8,0xffff800020ab0790 process=0xffff800020add500 user=0xffff800020b1c000, vmspace=0xfffffd807f008b80 estcpu=36, cpticks=1, pctcpu=0.18 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 55113 382294 25211 0 2 0 syz-executor.1 55113 96786 25211 0 3 0x4000080 select syz-executor.1 *15718 1958 87070 0 7 0x2 syz-executor.0 39979 25579 0 0 3 0x14200 bored sosplice 25211 269456 87070 0 3 0x82 nanosleep syz-executor.1 87070 367570 65776 0 3 0x82 thrsleep syz-fuzzer 87070 468833 65776 0 3 0x4000082 nanosleep syz-fuzzer 87070 509473 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 114381 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 80347 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 387473 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 371537 65776 0 3 0x4000082 kqread syz-fuzzer 87070 130067 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 31507 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 480388 65776 0 3 0x4000082 thrsleep syz-fuzzer 87070 418577 65776 0 3 0x4000082 thrsleep syz-fuzzer 65776 447929 11885 0 3 0x10008a pause ksh 11885 168794 24578 0 7 0x12 sshd 51263 93539 1 0 3 0x100083 ttyin getty 24578 203773 1 0 3 0x80 select sshd 29379 306840 83728 74 3 0x100092 bpf pflogd 83728 450686 1 0 3 0x80 netio pflogd 8649 72497 49714 73 3 0x100090 kqread syslogd 49714 11540 1 0 3 0x100082 netio syslogd 23985 217589 1 77 3 0x100090 poll dhclient 18358 465644 1 0 3 0x80 poll dhclient 54823 200538 0 0 2 0x14200 zerothread 70491 261339 0 0 3 0x14200 aiodoned aiodoned 75309 418839 0 0 3 0x14200 syncer update 68049 399358 0 0 3 0x14200 cleaner cleaner 79737 50572 0 0 3 0x14200 reaper reaper 78639 200776 0 0 3 0x14200 pgdaemon pagedaemon 65240 436082 0 0 3 0x14200 bored crynlk 13452 24230 0 0 3 0x14200 bored crypto 19860 208177 0 0 3 0x40014200 acpi0 acpi0 85976 60094 0 0 3 0x40014200 idle1 33790 166227 0 0 3 0x14200 bored softnet 30512 179187 0 0 3 0x14200 bored systqmp 73698 481369 0 0 3 0x14200 bored systq 3254 426445 0 0 3 0x40014200 bored softclock 19914 21559 0 0 3 0x40014200 idle0 14180 101694 0 0 3 0x14200 bored smr 1 340139 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 15718 (syz-executor.0) thread 0xffff800020ab09f8 (1958) exclusive rrwlock inode r = 0 (0xfffffd8061a163d0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:451 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:571 #5 vget+0x1c3 sys/kern/vfs_subr.c:672 #6 ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1323 #8 ufs_lookup+0x14b4 sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:91 #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:1785 #13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd8061a16700) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:451 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:571 #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:1785 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #9 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82684eb8) #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 Process 11885 (sshd) thread 0xffff800020ac18c0 (168794) exclusive rwlock netlock r = 0 (0xffffffff824ec968) #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 dofilewritev+0x1b7 sys/kern/sys_generic.c:364 #4 sys_write+0x83 sys/kern/sys_generic.c:284 #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 Kern Lim devbuf 9550 6434K 6942K 78643K 11897 0 0 pcb 13 8K 8K 78643K 138 0 0 rtable 96 12K 12K 78643K 419 0 0 ifaddr 77 13K 15K 78643K 173 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1502 0 0 iov 0 0K 16K 78643K 267 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 77K 78643K 1691 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 13 0 0 VM map 9 4K 4K 78643K 9 0 0 sem 11 1K 1K 78643K 16 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1809 196K 290K 78643K 12766 0 0 file desc 5 13K 25K 78643K 563 0 0 sigio 0 0K 0K 78643K 12 0 0 proc 62 63K 83K 78643K 532 0 0 subproc 32 2K 2K 78643K 51 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 39 0 0 in_multi 27 1K 2K 78643K 71 0 0 ether_multi 1 0K 0K 78643K 4 0 0 mrt 0 0K 0K 78643K 3 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 114 503K 503K 78643K 114 0 0 exec 0 0K 1K 78643K 276 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 124 71K 71K 78643K 2917 0 0 UVM aobj 59 7K 7K 78643K 65 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 116 0 0 NDP 15 0K 0K 78643K 36 0 0 temp 151 3559K 3631K 78643K 19513 0 0 kqueue 0 0K 0K 78643K 5 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 15 0 8 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 67 0 65 1 0 1 1 0 8 0 rtentry 112 71 0 36 2 0 2 2 0 8 0 unpcb 120 548 0 538 2 0 2 2 0 8 1 syncache 264 7 0 7 3 3 0 1 0 8 0 tcpqe 32 146 0 146 2 2 0 1 0 8 0 tcpcb 544 220 0 215 2 1 1 2 0 8 0 inpcb 280 1533 0 1524 7 2 5 5 0 8 4 rttmr 72 1 0 1 1 0 1 1 0 8 1 nd6 48 7 0 6 1 0 1 1 0 8 0 pkpcb 40 8 0 8 1 1 0 1 0 8 0 ppxss 1128 10 0 10 3 2 1 1 0 8 1 pffrag 232 12 0 12 2 1 1 1 0 482 1 pffrnode 88 12 0 12 2 1 1 1 0 8 1 pffrent 40 364 0 364 2 1 1 1 0 8 1 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 63 0 9 1 0 1 1 0 8 0 pfstkey 112 63 0 9 2 0 2 2 0 8 0 pfstate 328 63 0 7 5 0 5 5 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 256 309 0 138 15 1 14 14 0 8 2 art_table 32 310 0 138 2 0 2 2 0 8 0 art_node 16 70 0 37 1 0 1 1 0 8 0 sysvmsgpl 40 81 0 41 1 0 1 1 0 8 0 semupl 112 4 0 4 1 1 0 1 0 8 0 semapl 112 10 0 1 1 0 1 1 0 8 0 shmpl 112 63 0 6 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2340 0 938 46 0 46 46 0 8 0 ffsino 272 2340 0 938 95 0 95 95 0 8 0 nchpl 144 3475 0 1884 61 0 61 61 0 8 0 uvmvnodes 72 2707 0 0 50 0 50 50 0 8 0 vnodes 208 2707 0 0 143 0 143 143 0 8 0 namei 1024 10446 0 10446 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 7 0 0 1 0 1 1 0 8 0 vmpool 552 7 0 0 1 0 1 1 0 8 0 scsiplug 64 1 0 1 1 1 0 1 0 8 0 scxspl 192 10033 0 10033 11 9 2 7 0 8 2 plimitpl 152 53 0 45 1 0 1 1 0 8 0 sigapl 432 758 0 743 3 1 2 3 0 8 0 futexpl 56 13944 0 13944 1 0 1 1 0 8 1 knotepl 112 146 0 127 1 0 1 1 0 8 0 kqueuepl 104 190 0 188 1 0 1 1 0 8 0 pipepl 160 548 0 529 3 1 2 2 0 8 1 fdescpl 488 759 0 743 3 0 3 3 0 8 0 filepl 152 6866 0 6766 9 2 7 7 0 8 3 lockfpl 104 286 0 285 1 0 1 1 0 8 0 lockfspl 48 73 0 72 1 0 1 1 0 8 0 sessionpl 112 19 0 8 1 0 1 1 0 8 0 pgrppl 48 26 0 15 1 0 1 1 0 8 0 ucredpl 96 704 0 695 1 0 1 1 0 8 0 zombiepl 144 749 0 749 1 0 1 1 0 8 1 processpl 896 781 0 749 4 0 4 4 0 8 0 procpl 632 2073 0 2030 5 0 5 5 0 8 1 srpgc 64 4 0 4 2 2 0 1 0 8 0 sosppl 128 8 0 8 3 2 1 1 0 8 1 sockpl 384 2170 0 2150 10 2 8 8 0 8 5 mcl64k 65536 13 0 0 2 0 2 2 0 8 0 mcl16k 16384 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 15 0 0 2 0 2 2 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 7 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 162 0 0 20 0 20 20 0 8 0 mtagpl 80 11 0 0 1 0 1 1 0 8 0 mbufpl 256 803 0 0 48 0 48 48 0 8 0 bufpl 256 7786 0 1310 405 0 405 405 0 8 0 anonpl 16 90468 0 68693 104 2 102 102 0 124 14 amapchunkpl 152 5014 0 4856 17 7 10 14 0 158 2 amappl16 192 3998 0 2789 72 5 67 72 0 8 6 amappl14 176 56 0 51 1 0 1 1 0 8 0 amappl13 168 259 0 257 1 0 1 1 0 8 0 amappl12 160 10 0 7 2 1 1 1 0 8 0 amappl11 152 57 0 42 1 0 1 1 0 8 0 amappl10 144 11 0 6 1 0 1 1 0 8 0 amappl9 136 740 0 735 1 0 1 1 0 8 0 amappl8 128 312 0 280 2 0 2 2 0 8 0 amappl7 120 44 0 38 1 0 1 1 0 8 0 amappl6 112 65 0 55 1 0 1 1 0 8 0 amappl5 104 168 0 153 1 0 1 1 0 8 0 amappl4 96 1021 0 990 1 0 1 1 0 8 0 amappl3 88 147 0 142 1 0 1 1 0 8 0 amappl2 80 5373 0 5300 3 1 2 3 0 8 0 amappl1 72 26629 0 26191 25 15 10 20 0 8 0 amappl 80 2345 0 2294 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 64 0 6 1 0 1 1 0 8 0 uaddrrnd 24 766 0 743 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 766 0 743 1 0 1 1 0 8 0 vmmpekpl 168 10441 0 10408 2 0 2 2 0 8 0 vmmpepl 168 101182 0 98808 168 29 139 148 0 357 30 vmsppl 368 758 0 743 2 0 2 2 0 8 0 pdppl 4096 1539 0 1493 7 0 7 7 0 8 0 pvpl 32 272514 0 247504 237 2 235 235 0 265 32 pmappl 232 765 0 743 3 1 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 608 0 5 18 0 18 18 0 8 0