panic: kernel diagnostic assertion "pr->ps_threadcnt == 0" failed: file "/syzkaller/managers/setuid/kernel/sys/kern/kern_exit.c", line 888 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 154668 67546 32767 0x10 0x4000000 0 syz-executor *282865 64953 0 0x14000 0x200 1K reaper db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bd8f7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834f80a8,ffffffff8349ae1e,378,ffffffff8351a308) at __assert+0x29 sys/kern/subr_prf.c:-1 process_zap(ffff80003c3cd360) at process_zap+0x31d sys/kern/kern_exit.c:889 reaper(ffff800045ffd9f8) at reaper+0x2b0 sys/kern/kern_exit.c:525 end trace frame: 0x0, count: 10 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: kernel diagnostic assertion "pr->ps_threadcnt == 0" failed: file "/syzkaller/managers/setuid/kernel/sys/kern/kern_exit.c", line 888 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bd8f7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834f80a8,ffffffff8349ae1e,378,ffffffff8351a308) at __assert+0x29 sys/kern/subr_prf.c:-1 process_zap(ffff80003c3cd360) at process_zap+0x31d sys/kern/kern_exit.c:889 reaper(ffff800045ffd9f8) at reaper+0x2b0 sys/kern/kern_exit.c:525 end trace frame: 0x0, count: -5 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a1f4bf0 rbx 0xffff80002999ee07 rdx 0 rcx 0xffff800045ffd9f8 rax 0xffff80002999dff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x21c96ebad97ab0a r11 0x599c42ca39920c5a r12 0xffff80002999ec08 r13 0 r14 0 r15 0x1 rip 0xffffffff81d8c1b5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a1f4be0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (reaper) tid=282865 pid=64953 tcnt=1 stat=onproc flags process=14000 proc=200 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff800045fffc88,0xffff800045ffd770 process=0xffff800045ffb9c0 user=0xffff80002a1ef000, vmspace=0xffffffff839e6928 estcpu=0, cpticks=10, pctcpu=0.2, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 80365 451320 89196 0 2 0 syz-executor 13859 169566 70255 32767 2 0x10 syz-executor 13859 5995 70255 32767 3 0x4000090 fsleep syz-executor 15171 81804 26138 32767 2 0x10 syz-executor 15171 281681 26138 32767 3 0x4000090 fsleep syz-executor 67546 394985 49253 32767 2 0x10 syz-executor 67546 154668 49253 32767 7 0x4000010 syz-executor 22317 63689 89196 0 2 0x10000002 syz-executor 4749 67102 7074 32767 2 0x10 syz-executor 4749 475101 7074 32767 2 0x4000010 syz-executor 4749 437514 7074 32767 2 0x4000010 syz-executor 4749 338157 7074 32767 3 0x4000090 fsleep syz-executor 11719 180927 51914 32767 2 0x10 syz-executor 11719 103043 51914 32767 3 0x4000090 lockf syz-executor 11719 118698 51914 32767 3 0x4000090 fsleep syz-executor 7074 133885 36929 32767 3 0x90 nanoslp syz-executor 26138 233623 72828 32767 3 0x90 nanoslp syz-executor 51914 465053 91563 32767 3 0x90 nanoslp syz-executor 49253 283851 95588 32767 3 0x90 nanoslp syz-executor 70255 102314 43606 32767 3 0x90 nanoslp syz-executor 51898 443143 41641 32767 3 0x10 biowait syz-executor 72828 332741 89196 0 3 0x82 wait syz-executor 41641 395397 89196 0 3 0x82 wait syz-executor 43606 150892 89196 0 3 0x82 wait syz-executor 36929 462005 89196 0 3 0x82 wait syz-executor 91563 477901 89196 0 3 0x82 wait syz-executor 95588 518085 89196 0 3 0x82 wait syz-executor 89196 468121 92050 0 2 0x2 syz-executor 92050 494054 59919 0 3 0x10008a sigsusp ksh 59919 510040 74499 0 3 0x98 kqread sshd-session 74499 283078 86042 0 3 0x92 kqread sshd-session 72316 35622 1 0 3 0x100083 ttyin getty 86042 310523 1 0 3 0x88 kqread sshd 520 237723 57673 73 3 0x1100090 kqread syslogd 57673 524105 1 0 3 0x100082 sbwait syslogd 29797 455168 1 0 3 0x100080 kqread resolvd 76225 221186 98585 77 3 0x100092 kqread dhcpleased 58755 420992 98585 77 3 0x100092 kqread dhcpleased 98585 516533 1 0 3 0x80 kqread dhcpleased 8344 82194 0 0 3 0x14200 bored smr 20876 319282 0 0 2 0x14200 zerothread 46263 411133 0 0 3 0x14200 aiodoned aiodoned 92530 75950 0 0 3 0x14200 syncer update 45858 361925 0 0 3 0x14200 cleaner cleaner *64953 282865 0 0 7 0x14200 reaper 6816 508561 0 0 3 0x14200 pgdaemon pagedaemon 29814 362884 0 0 3 0x14200 bored viomb 65271 58826 0 0 3 0x40014200 acpi0 acpi0 46554 184237 0 0 3 0x40014200 idle1 96792 287028 0 0 3 0x14200 bored softnet1 27085 64080 0 0 3 0x14200 bored softnet0 7084 391558 0 0 3 0x14200 bored systqmp 4032 510896 0 0 3 0x14200 bored systq 78256 60852 0 0 3 0x14200 tmoslp softclockmp 72613 273030 0 0 3 0x40014200 tmoslp softclock 78549 457409 0 0 3 0x40014200 idle0 1 449104 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 67546 (syz-executor) thread 0xffff80003c400a88 (154668) exclusive rwlock fdlock r = 0 (0xffff80003c3e26a8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 sys_closefrom+0x1ed sys/kern/kern_descrip.c:1468 #3 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #3 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #4 Xsyscall+0x128 Process 51898 (syz-executor) thread 0xffff800045feefa8 (443143) exclusive rrwlock inode r = 0 (0xfffff6806b6198e0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline] #4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:159 #5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232 #6 ffs_inode_alloc+0x279 sys/ufs/ffs/ffs_alloc.c:393 #7 ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112 #8 VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394 #9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3062 #10 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffff6806d3159f0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:576 #5 vfs_lookup+0x12b sys/kern/vfs_lookup.c:431 #6 namei+0x7c5 sys/kern/vfs_lookup.c:250 #7 domkdirat+0x8b sys/kern/vfs_syscalls.c:3047 #8 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #9 Xsyscall+0x128 Process 64953 (reaper) thread 0xffff800045ffd9f8 (282865) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83af7200) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 #2 sleep_finish+0x2d8 sys/kern/kern_synch.c:369 #3 rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298 #4 knote_processexit+0x2b sys/kern/kern_event.c:2235 #5 reaper+0x26d sys/kern/kern_exit.c:515 #6 proc_trampoline+0x10 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11045 12014K 12034K 166960K 12142 0 pcb 17 12K 12K 166960K 17 0 rtable 197 5K 7K 166960K 354 0 pf 27 16K 16K 166960K 31 0 ifaddr 34 6K 7K 166960K 44 0 ifgroup 42 1K 2K 166960K 50 0 sysctl 1 1K 9K 166960K 5 0 counters 66 36K 37K 166960K 70 0 ioctlops 0 0K 4K 166960K 33 0 iov 0 0K 12K 166960K 10 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1288 81K 81K 166960K 1428 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 3 0 VM map 2 1K 1K 166960K 2 0 sem 5 0K 0K 166960K 5 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 21 74K 125K 166960K 233 0 proc 58 99K 147K 166960K 503 0 subproc 63 3K 4K 166960K 144 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 2 0K 0K 166960K 3 0 in_multi 77 5K 7K 166960K 99 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 6 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 67 307K 307K 166960K 67 0 exec 0 0K 1K 166960K 371 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 222 151K 177K 166960K 3456 0 UVM aobj 5 2K 2K 166960K 5 0 pinsyscall 42 84K 112K 166960K 1316 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 3 0 NDP 9 0K 2K 166960K 27 0 temp 32 9118K 9134K 166960K 3976 0 kqueue 20 29K 29K 166960K 42 0 SYN cache 2 16K 16K 166960K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 41 0 37 1 0 1 1 0 8 0 rtentry 176 113 0 23 6 0 6 6 0 8 0 unpcb 144 75 0 60 1 0 1 1 0 8 0 syncache 336 5 0 5 1 0 1 1 0 8 1 tcpqe 32 2 0 2 1 0 1 1 0 8 1 tcpcb 736 67 0 61 1 0 1 1 0 8 0 arp 136 19 0 4 1 0 1 1 0 8 0 ipq 40 1 0 0 1 0 1 1 0 8 0 ipqe 40 1 0 0 1 0 1 1 0 8 0 inpcb 328 138 0 125 2 0 2 2 0 8 0 nd6 152 25 0 6 1 0 1 1 0 8 0 kcovpl 48 16 0 9 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 468 0 88 30 0 30 30 0 8 4 art_table 40 469 0 88 5 0 5 5 0 8 0 art_node 32 113 0 31 1 0 1 1 0 8 0 sysvmsgpl 40 1 0 0 1 0 1 1 0 8 0 semapl 72 3 0 0 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 1650 0 175 93 0 93 93 0 8 0 ffsino 296 1650 0 175 114 0 114 114 0 8 0 nchpl 144 1931 0 234 64 0 64 64 0 8 0 vnodes 216 1803 0 0 101 0 101 101 0 8 0 namei 1024 6025 0 6024 1 0 1 1 0 8 0 percpumem 16 50 0 2 1 0 1 1 0 8 0 kstatmem 264 25 0 4 2 0 2 2 0 8 0 scxspl 216 6441 0 6440 4 2 2 3 1 8 1 plimitpl 152 129 0 107 2 0 2 2 0 8 0 sigapl 424 509 0 459 7 0 7 7 0 8 0 knotepl 120 291 0 0 9 0 9 9 0 8 0 kqueuepl 224 70 0 25 3 0 3 3 0 8 0 pipepl 344 153 0 123 3 0 3 3 0 8 0 fdescpl 528 493 0 460 4 0 4 4 0 8 0 filepl 160 2083 0 1844 11 0 11 11 0 8 0 lockfpl 104 26 0 22 1 0 1 1 0 8 0 lockfspl 48 12 0 9 1 0 1 1 0 8 0 sessionpl 144 36 0 21 1 0 1 1 0 8 0 pgrppl 48 52 0 30 1 0 1 1 0 8 0 ucredpl 104 194 0 177 1 0 1 1 0 8 0 zombiepl 144 460 0 459 1 0 1 1 0 8 0 processpl 1232 509 0 459 5 0 5 5 0 8 0 procpl 664 607 0 549 7 0 7 7 0 8 0 sockpl 752 254 0 222 5 0 5 5 0 8 1 mcl64k 65536 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 123 0 0 16 0 16 16 0 8 0 mcl2k 2048 24 0 0 3 0 3 3 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 208 0 0 13 0 13 13 0 8 0 bufpl 272 2311 0 102 148 0 148 148 0 8 0 anonpl 32 7394 0 0 60 0 60 60 0 247 0 amapchunkpl 152 9918 0 9443 30 0 30 30 0 158 8 amappl16 200 2057 0 2039 14 4 10 14 0 8 8 amappl15 192 3 0 3 1 1 0 1 0 8 0 amappl14 184 409 0 408 1 0 1 1 0 8 0 amappl13 176 119 0 109 1 0 1 1 0 8 0 amappl12 168 726 0 694 2 0 2 2 0 8 0 amappl11 160 4 0 4 1 1 0 1 0 8 0 amappl10 152 57 0 47 1 0 1 1 0 8 0 amappl9 144 271 0 271 1 1 0 1 0 8 0 amappl8 136 89 0 88 1 0 1 1 0 8 0 amappl7 128 143 0 130 1 0 1 1 0 8 0 amappl6 120 156 0 155 1 0 1 1 0 8 0 amappl5 112 91 0 84 1 0 1 1 0 8 0 amappl4 104 261 0 247 1 0 1 1 0 8 0 amappl3 96 1795 0 1685 5 1 4 4 0 8 0 amappl2 88 519 0 467 2 0 2 2 0 8 0 amappl1 80 10842 0 10284 15 0 15 15 0 8 1 amappl 88 2761 0 2601 5 0 5 5 0 92 0 uvmvnodes 80 101 0 0 3 0 3 3 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 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 72 4 0 0 1 0 1 1 0 8 0 uaddrrnd 24 494 0 461 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 494 0 461 1 0 1 1 0 8 0 vmmpekpl 168 6223 0 6176 3 0 3 3 0 8 0 vmmpepl 168 41193 0 39313 102 0 102 102 0 357 11 vmsppl 488 493 0 461 7 1 6 6 0 8 0 rwobjpl 80 15430 0 14521 26 0 26 26 0 8 3 pdppl 4096 995 0 922 107 24 83 97 0 8 10 pvpl 32 13660 0 0 111 0 111 111 0 265 0 pmappl 256 493 0 461 4 1 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 426 0 27 12 0 12 12 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8399fff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_lock(ffffffff83af6a00) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff83af6a00) at __mp_lock+0x192 sys/kern/kern_lock.c:173 intr_handler(ffff80002a354b30,ffff8000002a3480) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:560 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f rw_exit_write(ffff80003c3e2690) at rw_exit_write+0x10a rw_exited sys/kern/kern_rwlock.c:508 [inline] rw_exit_write(ffff80003c3e2690) at rw_exit_write+0x10a sys/kern/kern_rwlock.c:161 fdrelease(ffff80003c400a88,ae) at fdrelease+0x165 sys/kern/kern_descrip.c:763 sys_closefrom(ffff80003c400a88,ffff80002a354dc0,ffff80002a354d10) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471 syscall(ffff80002a354dc0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a354dc0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6b85c8db990, count: 4 ddb{0}> trace x86_ipi_db(ffffffff8399fff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_lock(ffffffff83af6a00) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline] __mp_lock(ffffffff83af6a00) at __mp_lock+0x192 sys/kern/kern_lock.c:173 intr_handler(ffff80002a354b30,ffff8000002a3480) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:560 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f rw_exit_write(ffff80003c3e2690) at rw_exit_write+0x10a rw_exited sys/kern/kern_rwlock.c:508 [inline] rw_exit_write(ffff80003c3e2690) at rw_exit_write+0x10a sys/kern/kern_rwlock.c:161 fdrelease(ffff80003c400a88,ae) at fdrelease+0x165 sys/kern/kern_descrip.c:763 sys_closefrom(ffff80003c400a88,ffff80002a354dc0,ffff80002a354d10) at sys_closefrom+0x13c sys/kern/kern_descrip.c:1471 syscall(ffff80002a354dc0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a354dc0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6b85c8db990, count: -11 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bd8f7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834f80a8,ffffffff8349ae1e,378,ffffffff8351a308) at __assert+0x29 sys/kern/subr_prf.c:-1 process_zap(ffff80003c3cd360) at process_zap+0x31d sys/kern/kern_exit.c:889 reaper(ffff800045ffd9f8) at reaper+0x2b0 sys/kern/kern_exit.c:525 end trace frame: 0x0, count: 10 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834bd8f7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff834f80a8,ffffffff8349ae1e,378,ffffffff8351a308) at __assert+0x29 sys/kern/subr_prf.c:-1 process_zap(ffff80003c3cd360) at process_zap+0x31d sys/kern/kern_exit.c:889 reaper(ffff800045ffd9f8) at reaper+0x2b0 sys/kern/kern_exit.c:525 end trace frame: 0x0, count: -5