panic: WpAoRoNlI_NcGa:c hSeP_Li tNeOmT_ mLagOWiEcR_EchDe cONk :S YmSbCuAfLLp l 2c p-1u 18f5re4e56 5li2s6 tE XmIodT if0 iae d : Stopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND *300051 42796 0 0x2 0 0 syz-executor.1 118095 43878 0 0x12 0 1 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc5530, 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 0xfffffd8064bbbf00+16 0x0!=0x90f3a74d470844a2 ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc5530, count: -1 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff800022da91c0 rbx 0 rdx 0xffff800020aa0018 rcx 0 rax 0x3b r8 0xffffffff8162ae5f kprintf+0x16f r9 0x1 r10 0x25 r11 0x9f00815c5e61d645 r12 0 r13 0 r14 0xffff800020aa0018 r15 0 rip 0xffffffff820853f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800022da9140 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{0}> show proc PROC (syz-executor.1) pid=300051 stat=onproc flags process=2 proc=0 pri=81, usrpri=81, nice=20 forw=0xffffffffffffffff, list=0xffff800020aa0c70,0xffff800020aa1170 process=0xffff800020aa2e30 user=0xffff800022da4000, vmspace=0xfffffd806e7885c8 estcpu=36, cpticks=1, pctcpu=1.21 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 36998 374812 42796 0 2 0 syz-executor.1 20898 349739 80627 0 3 0x2 biowait syz-executor.0 14903 510880 0 0 3 0x14200 bored sosplice *42796 300051 80627 0 7 0x2 syz-executor.1 80627 204901 62171 0 3 0x82 thrsleep syz-fuzzer 80627 266116 62171 0 3 0x4000082 nanosleep syz-fuzzer 80627 82646 62171 0 3 0x4000082 thrsleep syz-fuzzer 80627 189096 62171 0 3 0x4000082 thrsleep syz-fuzzer 80627 491447 62171 0 3 0x4000082 thrsleep syz-fuzzer 80627 133505 62171 0 3 0x4000082 kqread syz-fuzzer 80627 39285 62171 0 3 0x4000082 thrsleep syz-fuzzer 80627 19457 62171 0 3 0x4000082 thrsleep syz-fuzzer 80627 451305 62171 0 3 0x4000082 nanosleep syz-fuzzer 80627 57884 62171 0 3 0x4000082 thrsleep syz-fuzzer 62171 15190 43878 0 3 0x10008a pause ksh 43878 118095 19185 0 7 0x12 sshd 90915 361885 1 0 3 0x100083 ttyin getty 19185 410781 1 0 3 0x80 select sshd 69789 486971 27464 74 3 0x100092 bpf pflogd 27464 487334 1 0 3 0x80 netio pflogd 33137 294248 50303 73 3 0x100090 kqread syslogd 50303 347176 1 0 3 0x100082 netio syslogd 65384 316226 1 77 3 0x100090 poll dhclient 75343 429494 1 0 3 0x80 poll dhclient 20138 469736 0 0 3 0x14200 pgzero zerothread 45071 324233 0 0 3 0x14200 aiodoned aiodoned 96140 190635 0 0 3 0x14200 syncer update 46290 410261 0 0 3 0x14200 cleaner cleaner 91880 263297 0 0 3 0x14200 reaper reaper 43463 373145 0 0 3 0x14200 pgdaemon pagedaemon 97514 33686 0 0 3 0x14200 bored crynlk 95218 505715 0 0 3 0x14200 bored crypto 9520 135446 0 0 3 0x40014200 acpi0 acpi0 54702 462034 0 0 3 0x40014200 idle1 61172 442000 0 0 3 0x14200 bored softnet 61513 422971 0 0 3 0x14200 bored systqmp 72903 30635 0 0 3 0x14200 bored systq 98955 318542 0 0 3 0x40014200 bored softclock 56973 197462 0 0 3 0x40014200 idle0 56643 43436 0 0 3 0x14200 bored smr 1 366343 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex vmmpekpl r = 0 (0xffffffff8264d468) #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 uvm_mapent_alloc+0x394 sys/uvm/uvm_map.c:1741 #5 uvm_map+0x2a5 sys/uvm/uvm_map.c:1224 #6 uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:334 #7 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #8 fork1+0x295 sys/kern/kern_fork.c:366 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #10 Xsyscall+0x128 Process 20898 (syz-executor.0) thread 0xffff800020aa09f8 (349739) exclusive rrwlock inode r = 0 (0xfffffd806eb17a28) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:453 #3 VOP_LOCK+0xf9 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:571 #5 vget+0x1c8 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:1776 #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 (0xfffffd806d8d8928) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:453 #3 VOP_LOCK+0xf9 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:1776 #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 Process 42796 (syz-executor.1) thread 0xffff800020aa0018 (300051) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82633630) #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 vmmpekpl r = 0 (0xffffffff8264d468) #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 uvm_mapent_alloc+0x394 sys/uvm/uvm_map.c:1741 #5 uvm_map+0x2a5 sys/uvm/uvm_map.c:1224 #6 uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:334 #7 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #8 fork1+0x295 sys/kern/kern_fork.c:366 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #10 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9523 7060K 7574K 78643K 11462 0 pcb 13 8K 8K 78643K 100 0 rtable 108 4K 4K 78643K 406 0 ifaddr 81 16K 17K 78643K 142 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1491 0 iov 0 0K 48K 78643K 83 0 mount 1 1K 1K 78643K 1 0 vnodes 1217 76K 77K 78643K 1652 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 7 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 102 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 451 0 sigio 0 0K 0K 78643K 34 0 proc 61 63K 83K 78643K 592 0 subproc 32 2K 2K 78643K 68 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 20 0 in_multi 71 3K 3K 78643K 107 0 ether_multi 1 0K 0K 78643K 4 0 mrt 0 0K 0K 78643K 6 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 67 307K 307K 78643K 67 0 exec 0 0K 1K 78643K 286 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 126 55K 55K 78643K 2707 0 UVM aobj 44 2K 2K 78643K 46 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 102 0 NDP 12 0K 0K 78643K 31 0 temp 135 3027K 3658K 78643K 6042 0 kqueue 0 0K 0K 78643K 4 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 13 0 7 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 52 0 50 1 0 1 1 0 8 0 rtentry 112 81 0 37 2 0 2 2 0 8 0 unpcb 120 299 0 289 1 0 1 1 0 8 0 syncache 264 6 0 6 2 2 0 1 0 8 0 tcpqe 32 77 0 77 1 1 0 1 0 8 0 tcpcb 544 177 0 173 1 0 1 1 0 8 0 inpcb 280 685 0 678 7 5 2 3 0 8 1 rttmr 72 3 0 3 2 1 1 1 0 8 1 nd6 48 9 0 5 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 1 0 1 0 8 0 ppxss 1128 3 0 3 3 2 1 1 0 8 1 pffrag 232 10 0 10 4 4 0 1 0 482 0 pffrnode 88 10 0 10 4 4 0 1 0 8 0 pffrent 40 365 0 365 4 4 0 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 49 0 29 1 0 1 1 0 8 0 pfstkey 112 49 0 29 1 0 1 1 0 8 0 pfstate 328 49 0 27 3 0 3 3 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 256 391 0 174 17 3 14 15 0 8 0 art_table 32 392 0 174 2 0 2 2 0 8 0 art_node 16 80 0 40 1 0 1 1 0 8 0 sysvmsgpl 40 60 0 37 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 100 0 90 1 0 1 1 0 8 0 shmpl 112 44 0 2 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2238 0 832 46 0 46 46 0 8 0 ffsino 272 2238 0 832 94 0 94 94 0 8 0 nchpl 144 3117 0 1511 61 0 61 61 0 8 0 uvmvnodes 72 2518 0 0 46 0 46 46 0 8 0 vnodes 208 2518 0 0 133 0 133 133 0 8 0 namei 1024 10303 0 10303 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 4 0 0 1 0 1 1 0 8 0 vmpool 560 6 0 2 1 0 1 1 0 8 0 scxspl 192 8605 0 8604 12 11 1 7 0 8 0 plimitpl 152 47 0 39 1 0 1 1 0 8 0 sigapl 432 644 0 629 3 1 2 3 0 8 0 futexpl 56 10622 0 10622 1 0 1 1 0 8 1 knotepl 112 129 0 110 1 0 1 1 0 8 0 kqueuepl 104 93 0 91 1 0 1 1 0 8 0 pipepl 112 398 0 379 2 1 1 2 0 8 0 fdescpl 488 645 0 629 3 0 3 3 0 8 0 filepl 152 5668 0 5568 14 8 6 7 0 8 2 lockfpl 104 116 0 115 1 0 1 1 0 8 0 lockfspl 48 47 0 46 1 0 1 1 0 8 0 sessionpl 112 20 0 9 1 0 1 1 0 8 0 pgrppl 48 24 0 13 1 0 1 1 0 8 0 ucredpl 96 1483 0 1474 1 0 1 1 0 8 0 zombiepl 144 629 0 629 1 0 1 1 0 8 1 processpl 904 661 0 629 4 0 4 4 0 8 0 procpl 632 1832 0 1791 6 1 5 5 0 8 1 srpgc 64 2 0 2 1 1 0 1 0 8 0 sosppl 128 7 0 7 2 2 0 1 0 8 0 sockpl 384 1065 0 1046 11 7 4 6 0 8 2 mcl64k 65536 258 0 0 33 0 33 33 0 8 1 mcl16k 16384 3 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 9 0 0 2 0 2 2 0 8 0 mcl4k 4096 15 0 0 2 0 2 2 0 8 0 mcl2k2 2112 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 171 0 0 21 0 21 21 0 8 0 mtagpl 80 23 0 0 1 0 1 1 0 8 0 mbufpl 256 421 0 0 24 0 24 24 0 8 0 bufpl 280 7386 0 1354 431 0 431 431 0 8 0 anonpl 16 89020 0 69701 96 16 80 95 0 125 0 amapchunkpl 152 4618 0 4460 18 10 8 14 0 158 0 amappl16 192 3372 0 2322 77 23 54 65 0 8 1 amappl15 184 156 0 152 1 0 1 1 0 8 0 amappl14 176 39 0 37 1 0 1 1 0 8 0 amappl12 160 118 0 111 1 0 1 1 0 8 0 amappl11 152 263 0 245 1 0 1 1 0 8 0 amappl10 144 18 0 13 1 0 1 1 0 8 0 amappl9 136 629 0 626 1 0 1 1 0 8 0 amappl8 128 142 0 115 1 0 1 1 0 8 0 amappl7 120 123 0 111 1 0 1 1 0 8 0 amappl6 112 247 0 241 1 0 1 1 0 8 0 amappl5 104 255 0 239 1 0 1 1 0 8 0 amappl4 96 875 0 845 1 0 1 1 0 8 0 amappl3 88 167 0 159 1 0 1 1 0 8 0 amappl2 80 4208 0 4143 3 1 2 3 0 8 0 amappl1 72 24582 0 24140 25 14 11 21 0 8 0 amappl 80 2117 0 2068 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 45 0 2 1 0 1 1 0 8 0 uaddrrnd 24 651 0 631 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 651 0 631 1 0 1 1 0 8 0 vmmpekpl 168 9542 0 9507 2 0 2 2 0 8 0 vmmpepl 168 89561 0 87344 171 52 119 140 0 357 14 vmsppl 368 650 0 631 2 0 2 2 0 8 0 pdppl 4096 1309 0 1266 6 0 6 6 0 8 0 pvpl 32 260477 0 238030 223 34 189 221 0 265 3 pmappl 232 650 0 631 3 1 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 217 0 7 6 0 6 6 0 8 0