panic: timeout_add: to_ticks (-2) < 0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 187546 76209 0 0 0 0 syz-executor.1 * 79915 76209 0 0 0x4000000 1K syz-executor.1 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x174 sys/kern/subr_prf.c:208 timeout_add(ffff80000066d060,fffffffe) at timeout_add+0x194 sys/kern/kern_timeout.c:190 pcppi_bell(ffff80000066d000,5fe,fffffffe,1) at pcppi_bell+0x2a0 sys/dev/isa/pcppi.c:234 spkrioctl(1b00,20005302,ffff800020bfd910,2,ffff800020b432d8) at spkrioctl+0x230 tone sys/dev/isa/spkr.c:89 [inline] spkrioctl(1b00,20005302,ffff800020bfd910,2,ffff800020b432d8) at spkrioctl+0x230 sys/dev/isa/spkr.c:503 VOP_IOCTL(fffffd8074527298,20005302,ffff800020bfd910,2,fffffd807f7c7a20,ffff800020b432d8) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290 vn_ioctl(fffffd806cf4c7c8,20005302,ffff800020bfd910,ffff800020b432d8) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512 sys_ioctl(ffff800020b432d8,ffff800020bfda58,ffff800020bfda40) at sys_ioctl+0x646 syscall(ffff800020bfdaf0) at syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bfdaf0) at syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,ffffffffffffff88,0,3,69b129f5010) at Xsyscall+0x128 end of kernel end trace frame: 0x69d2a37d5b0, count: 5 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 timeout_add: to_ticks (-2) < 0 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x174 sys/kern/subr_prf.c:208 timeout_add(ffff80000066d060,fffffffe) at timeout_add+0x194 sys/kern/kern_timeout.c:190 pcppi_bell(ffff80000066d000,5fe,fffffffe,1) at pcppi_bell+0x2a0 sys/dev/isa/pcppi.c:234 spkrioctl(1b00,20005302,ffff800020bfd910,2,ffff800020b432d8) at spkrioctl+0x230 tone sys/dev/isa/spkr.c:89 [inline] spkrioctl(1b00,20005302,ffff800020bfd910,2,ffff800020b432d8) at spkrioctl+0x230 sys/dev/isa/spkr.c:503 VOP_IOCTL(fffffd8074527298,20005302,ffff800020bfd910,2,fffffd807f7c7a20,ffff800020b432d8) at VOP_IOCTL+0x9a sys/kern/vfs_vops.c:290 vn_ioctl(fffffd806cf4c7c8,20005302,ffff800020bfd910,ffff800020b432d8) at vn_ioctl+0xc9 sys/kern/vfs_vnops.c:512 sys_ioctl(ffff800020b432d8,ffff800020bfda58,ffff800020bfda40) at sys_ioctl+0x646 syscall(ffff800020bfdaf0) at syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff800020bfdaf0) at syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,ffffffffffffff88,0,3,69b129f5010) at Xsyscall+0x128 end of kernel end trace frame: 0x69d2a37d5b0, count: -10 ddb{1}> show registers rdi 0xffffffff812c7447 db_enter+0x17 rsi 0xe13 rbp 0xffff800020bfd530 rbx 0xffff800020bfd5e0 rdx 0xe14 rcx 0xffff800002b49000 rax 0xffff800002b49000 r8 0xffffffff8155ffb3 kprintf+0x183 r9 0x1 r10 0x25 r11 0x50268002119616e8 r12 0x3000000008 r13 0xffff800020bfd540 r14 0x100 r15 0x1 rip 0xffffffff812c7448 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020bfd520 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=79915 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020b43530,0xffffffff8233fe30 process=0xffff800020b45078 user=0xffff800020bf8000, vmspace=0xfffffd807efff870 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 76209 187546 38157 0 7 0 syz-executor.1 *76209 79915 38157 0 7 0x4000000 syz-executor.1 81434 418603 15730 0 3 0x2 biowait syz-executor.0 22350 314188 1 0 3 0x100083 ttyin getty 46895 454297 0 0 3 0x14200 bored sosplice 38157 74532 15730 0 3 0x82 nanosleep syz-executor.1 15730 196828 12252 0 3 0x82 thrsleep syz-fuzzer 15730 334036 12252 0 3 0x4000082 nanosleep syz-fuzzer 15730 144092 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 9992 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 482930 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 483651 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 506189 12252 0 3 0x4000082 kqread syz-fuzzer 15730 85799 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 90125 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 488223 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 97400 12252 0 3 0x4000082 thrsleep syz-fuzzer 15730 350801 12252 0 3 0x4000082 thrsleep syz-fuzzer 12252 258735 87507 0 3 0x10008a pause ksh 87507 219035 22061 0 3 0x92 select sshd 22061 26610 1 0 3 0x80 select sshd 26459 22527 89029 73 3 0x100090 kqread syslogd 89029 91034 1 0 3 0x100082 netio syslogd 72566 239329 1 77 3 0x100090 poll dhclient 18221 407392 1 0 3 0x80 poll dhclient 98539 393064 0 0 3 0x14200 pgzero zerothread 11231 355806 0 0 3 0x14200 aiodoned aiodoned 12539 153870 0 0 3 0x14200 syncer update 93907 128026 0 0 3 0x14200 cleaner cleaner 27767 101672 0 0 3 0x14200 reaper reaper 33127 522436 0 0 3 0x14200 pgdaemon pagedaemon 28913 43952 0 0 3 0x14200 bored crynlk 17141 273337 0 0 3 0x14200 bored crypto 90057 278216 0 0 3 0x40014200 acpi0 acpi0 786 303475 0 0 3 0x40014200 idle1 45600 345713 0 0 3 0x14200 bored softnet 57362 492839 0 0 3 0x14200 bored systqmp 68397 145243 0 0 3 0x14200 bored systq 82622 117501 0 0 3 0x40014200 bored softclock 87564 421250 0 0 3 0x40014200 idle0 1 123485 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 76209 (syz-executor.1) thread 0xffff800020b432d8 (79915) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8230eba0) locked @ /syzkaller/managers/multicore/kernel/sys/sys/syscall_mi.h:90 #0 witness_lock+0x58a sys/kern/subr_witness.c:1205 #1 syscall+0x47f mi_syscall sys/sys/syscall_mi.h:91 [inline] #1 syscall+0x47f sys/arch/amd64/amd64/trap.c:574 #2 Xsyscall+0x128 Process 81434 (syz-executor.0) thread 0xffff800020b43788 (418603) exclusive rrwlock inode r = 0 (0xfffffd8077eb1d58) locked @ /syzkaller/managers/multicore/kernel/sys/ufs/ufs/ufs_ihash.c:140 #0 witness_lock+0x58a sys/kern/subr_witness.c:1205 #1 _rw_enter+0x44d sys/kern/kern_rwlock.c:280 #2 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #3 ufs_ihashins+0x67 sys/ufs/ufs/ufs_ihash.c:140 #4 ffs_vget+0x13d sys/ufs/ffs/ffs_vfsops.c:1352 #5 ffs_inode_alloc+0x1c3 sys/ufs/ffs/ffs_alloc.c:392 #6 ufs_mkdir+0x10f sys/ufs/ufs/ufs_vnops.c:1164 #7 VOP_MKDIR+0x76 sys/kern/vfs_vops.c:449 #8 domkdirat+0x12d sys/kern/vfs_syscalls.c:2881 #9 syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] #9 syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 #10 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd80749c1700) locked @ /syzkaller/managers/multicore/kernel/sys/ufs/ufs/ufs_vnops.c:1547 #0 witness_lock+0x58a sys/kern/subr_witness.c:1205 #1 _rw_enter+0x44d sys/kern/kern_rwlock.c:280 #2 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #3 VOP_LOCK+0x57 sys/kern/vfs_vops.c:602 #4 vn_lock+0x6e sys/kern/vfs_vnops.c:549 #5 vfs_lookup+0xf5 sys/kern/vfs_lookup.c:387 #6 namei+0x4b2 sys/kern/vfs_lookup.c:224 #7 domkdirat+0x81 sys/kern/vfs_syscalls.c:2866 #8 syscall+0x5ac mi_syscall sys/sys/syscall_mi.h:99 [inline] #8 syscall+0x5ac sys/arch/amd64/amd64/trap.c:574 #9 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9498 6342K 6357K 78643K 11024 0 0 pcb 23 9K 10K 78643K 620 0 0 rtable 100 3K 4K 78643K 601 0 0 ifaddr 49 12K 13K 78643K 224 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 27 0 0 iov 0 0K 16K 78643K 102 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1196 75K 75K 78643K 1974 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 23 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 173 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1792 194K 288K 78643K 12592 0 0 file desc 5 13K 21K 78643K 1178 0 0 sigio 0 0K 0K 78643K 16 0 0 proc 42 38K 70K 78643K 542 0 0 subproc 64 65538K 67586K 78643K 279 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 187 0 0 in_multi 33 2K 2K 78643K 152 0 0 ether_multi 1 0K 0K 78643K 8 0 0 mrt 0 0K 0K 78643K 1 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 72 318K 318K 78643K 72 0 0 exec 0 0K 1K 78643K 265 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 96 21K 30K 78643K 4529 0 0 UVM aobj 55 3K 3K 78643K 61 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 30 0 0 NDP 9 0K 0K 78643K 69 0 0 temp 149 2366K 2432K 78643K 6330 0 0 kqueue 0 0K 0K 78643K 6 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 10 0 6 1 0 1 1 0 8 0 inpcbpl 280 567 0 560 1 0 1 1 0 8 0 plimitpl 152 37 0 30 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 95 0 55 2 0 2 2 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpcb 544 215 0 211 1 0 1 1 0 8 0 nd6 48 16 0 12 1 0 1 1 0 8 0 ppxss 1128 28 0 28 8 8 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 448 0 260 12 0 12 12 0 8 0 art_table 32 449 0 260 2 0 2 2 0 8 0 art_node 16 94 0 60 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 7 1 0 1 1 0 8 0 semapl 112 171 0 161 1 0 1 1 0 8 0 shmpl 112 59 0 6 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 3556 0 2142 46 0 46 46 0 8 0 ffsino 272 3556 0 2142 95 0 95 95 0 8 0 nchpl 144 5420 0 3809 61 0 61 61 0 8 0 uvmvnodes 72 3813 0 0 70 0 70 70 0 8 0 vnodes 200 3813 0 0 201 0 201 201 0 8 0 namei 1024 16024 0 16023 2 1 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scsiplug 64 5 0 5 3 3 0 1 0 8 0 scxspl 192 14035 0 14034 12 11 1 6 0 8 0 sigapl 432 1329 0 1316 2 0 2 2 0 8 0 futexpl 56 16301 0 16301 1 0 1 1 0 8 1 knotepl 112 400 0 373 3 2 1 2 0 8 0 kqueuepl 104 325 0 323 1 0 1 1 0 8 0 pipepl 112 922 0 903 4 3 1 2 0 8 0 fdescpl 488 1330 0 1316 3 1 2 3 0 8 0 filepl 152 8094 0 7999 12 7 5 5 0 8 1 lockfpl 104 386 0 385 7 6 1 1 0 8 0 lockfspl 32 556 0 555 7 6 1 1 0 8 0 sessionpl 112 24 0 14 1 0 1 1 0 8 0 pgrppl 48 36 0 26 1 0 1 1 0 8 0 ucredpl 96 2221 0 2214 1 0 1 1 0 8 0 zombiepl 144 1316 0 1316 3 2 1 1 0 8 1 processpl 840 1345 0 1316 4 0 4 4 0 8 0 procpl 600 3802 0 3761 4 0 4 4 0 8 0 srpgc 64 36 0 36 1 1 0 1 0 8 0 sosppl 128 19 0 19 7 7 0 1 0 8 0 sockpl 384 1116 0 1099 9 6 3 3 0 8 1 mcl64k 65536 614 0 0 76 12 64 65 0 8 1 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 13 0 0 2 0 2 2 0 8 0 mcl9k 9216 8 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 128 0 0 14 1 13 14 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 718 0 0 35 0 35 35 0 8 0 bufpl 256 7331 0 1019 395 0 395 395 0 8 0 anonpl 16 137881 0 130220 87 53 34 49 0 125 0 amapchunkpl 152 7731 0 7640 23 18 5 9 0 158 0 amappl16 192 6864 0 6443 68 44 24 34 0 8 2 amappl15 184 8 0 7 1 0 1 1 0 8 0 amappl14 176 10 0 9 2 1 1 1 0 8 0 amappl13 168 552 0 548 1 0 1 1 0 8 0 amappl12 160 43 0 40 2 1 1 1 0 8 0 amappl11 152 772 0 760 1 0 1 1 0 8 0 amappl10 144 56 0 55 2 1 1 1 0 8 0 amappl9 136 924 0 920 1 0 1 1 0 8 0 amappl8 128 210 0 184 1 0 1 1 0 8 0 amappl7 120 565 0 559 1 0 1 1 0 8 0 amappl6 112 53 0 47 1 0 1 1 0 8 0 amappl5 104 143 0 132 1 0 1 1 0 8 0 amappl4 96 288 0 263 2 1 1 2 0 8 0 amappl3 88 175 0 169 1 0 1 1 0 8 0 amappl2 80 11783 0 11730 2 0 2 2 0 8 0 amappl1 72 37030 0 36615 24 14 10 19 0 8 0 amappl 72 4053 0 4018 1 0 1 1 0 75 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 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 60 0 6 1 0 1 1 0 8 0 uaddrrnd 24 1330 0 1316 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1330 0 1316 1 0 1 1 0 8 0 vmmpekpl 168 15172 0 15149 2 0 2 2 0 8 0 vmmpepl 168 146664 0 145293 114 44 70 75 0 357 5 vmsppl 360 1329 0 1316 2 0 2 2 0 8 0 pdppl 4096 2668 0 2632 6 1 5 6 0 8 0 pvpl 32 388873 0 378206 224 115 109 127 0 265 19 pmappl 224 1329 0 1316 1 0 1 1 0 8 0 extentpl 40 39 0 25 1 0 1 1 0 8 0 phpool 112 645 0 17 18 0 18 18 0 8 0