kern.securelevel: 0 -> 1 creating runtime link editor directory cache. preserving editor files. starting network daemons: sshd. starting local daemons:. Tue Jul 9 07:55:23 PDT 2019 OpenBSD/amd64 (ci-openbsd-main-7.c.syzkaller.internal) (tty00) Warning: Permanently added '10.128.0.139' (ECDSA) to the list of known hosts. executing program login: panic: kernel diagnostic assertion "cpipe->pipe_buffer.cnt == 0" failed: file "/syzkaller/managers/main/kernel/sys/kern/sys_pipe.c", line 223 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *260067 45648 0 0x2 0x4000000 0 syz-executor4393 db_enter() at db_enter+0x18 panic() at panic+0x15c __assert(ffffffff81f8ad79,ffffffff81f99791,df,ffffffff81f2c9d6) at __assert+0x2e pipespace(fffffd803b498628,10000) at pipespace+0x16f pipe_write(fffffd803616a878,ffff800014990778,0) at pipe_write+0x952 dofilewritev(ffff8000ffff5648,7,ffff800014990778,0,ffff800014990880) at dofilewritev+0x1ac sys_write(ffff8000ffff5648,ffff800014990818,ffff800014990880) at sys_write+0x83 syscall(ffff8000149908e0) at syscall+0x508 Xsyscall(6,0,5e39bfb0138,0,5e39bfb0118,5e39bfb0110) at Xsyscall+0x128 end of kernel end trace frame: 0x5e61fb4ec30, count: 6 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic kernel diagnostic assertion "cpipe->pipe_buffer.cnt == 0" failed: file "/syzkaller/managers/main/kernel/sys/kern/sys_pipe.c", line 223 ddb> trace db_enter() at db_enter+0x18 panic() at panic+0x15c __assert(ffffffff81f8ad79,ffffffff81f99791,df,ffffffff81f2c9d6) at __assert+0x2e pipespace(fffffd803b498628,10000) at pipespace+0x16f pipe_write(fffffd803616a878,ffff800014990778,0) at pipe_write+0x952 dofilewritev(ffff8000ffff5648,7,ffff800014990778,0,ffff800014990880) at dofilewritev+0x1ac sys_write(ffff8000ffff5648,ffff800014990818,ffff800014990880) at sys_write+0x83 syscall(ffff8000149908e0) at syscall+0x508 Xsyscall(6,0,5e39bfb0138,0,5e39bfb0118,5e39bfb0110) at Xsyscall+0x128 end of kernel end trace frame: 0x5e61fb4ec30, count: -9 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000149904f0 rbx 0xffff8000149905a0 rdx 0x2 rcx 0x1 rax 0x1 r8 0xffff8000149904b0 r9 0x1 r10 0x9ddac5ae6114b634 r11 0xd55d3bf75e7a45ac r12 0x3000000008 r13 0xffff800014990500 r14 0x100 r15 0x1 rip 0xffffffff81c87f68 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000149904e0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor4393) pid=260067 stat=onproc flags process=2 proc=4000000 pri=16, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff4500,0xffff8000ffff58d0 process=0xffff800014942018 user=0xffff80001498b000, vmspace=0xfffffd803f013110 estcpu=1, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 45648 253492 71971 0 2 0x482 syz-executor4393 45648 115731 71971 0 2 0x4000002 syz-executor4393 45648 38703 71971 0 3 0x4000082 pipewr syz-executor4393 *45648 260067 71971 0 7 0x4000002 syz-executor4393 45648 103528 71971 0 3 0x4000082 fsleep syz-executor4393 45648 75861 71971 0 3 0x4000082 fsleep syz-executor4393 45648 392146 71971 0 3 0x4000082 fsleep syz-executor4393 45648 455744 71971 0 2 0x4000002 syz-executor4393 71971 234144 99194 0 3 0x10008a pause ksh 99194 515210 34369 0 3 0x92 select sshd 12737 522352 1 0 3 0x100083 ttyin getty 34369 510706 1 0 3 0x80 select sshd 16110 153239 77536 73 3 0x100090 kqread syslogd 77536 136398 1 0 3 0x100082 netio syslogd 44596 435276 1 77 3 0x100090 poll dhclient 10734 482124 1 0 3 0x80 poll dhclient 82322 236152 0 0 3 0x14200 pgzero zerothread 64891 67611 0 0 3 0x14200 aiodoned aiodoned 44407 386341 0 0 3 0x14200 syncer update 89078 343488 0 0 3 0x14200 cleaner cleaner 49214 340878 0 0 3 0x14200 reaper reaper 77519 439946 0 0 3 0x14200 pgdaemon pagedaemon 42863 345769 0 0 3 0x14200 bored crynlk 91543 86990 0 0 3 0x14200 bored crypto 25176 50148 0 0 3 0x40014200 acpi0 acpi0 198 190801 0 0 3 0x14200 bored softnet 57872 57968 0 0 3 0x14200 bored systqmp 26068 116655 0 0 3 0x14200 bored systq 94205 30204 0 0 3 0x40014200 bored softclock 79993 270526 0 0 3 0x40014200 idle0 81989 92445 0 0 3 0x14200 bored smr 1 176016 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9428 6307K 6308K 78643K 10521 0 0 pcb 23 9K 9K 78643K 55 0 0 rtable 61 1K 2K 78643K 116 0 0 ifaddr 21 7K 7K 78643K 21 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 13 0 0 iov 0 0K 12K 78643K 2 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1180 74K 74K 78643K 1185 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 1K 78643K 2 0 0 VM map 2 0K 0K 78643K 2 0 0 sem 2 0K 0K 78643K 2 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 1 0K 0K 78643K 1 0 0 proc 40 30K 38K 78643K 257 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 in_multi 11 0K 0K 78643K 11 0 0 ether_multi 1 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 18 79K 79K 78643K 18 0 0 exec 0 0K 1K 78643K 152 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 65 11K 11K 78643K 713 0 0 UVM aobj 2 2K 2K 78643K 2 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 NDP 3 0K 0K 78643K 3 0 0 temp 30 2707K 2771K 78643K 1715 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 2 0 0 1 0 1 1 0 8 0 inpcbpl 280 22 0 16 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 syncache 264 5 0 5 1 0 1 1 0 8 1 tcpcb 544 8 0 5 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 96 0 0 6 0 6 6 0 8 0 art_table 32 97 0 0 1 0 1 1 0 8 0 art_node 16 22 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1392 0 16 45 0 45 45 0 8 0 ffsino 240 1392 0 16 81 0 81 81 0 8 0 nchpl 144 1567 0 31 57 0 57 57 0 8 0 uvmvnodes 72 1401 0 0 26 0 26 26 0 8 0 vnodes 200 1401 0 0 74 0 74 74 0 8 0 namei 1024 3367 0 3367 2 1 1 1 0 8 1 scxspl 192 2634 0 2634 8 2 6 6 0 8 6 plimitpl 152 14 0 8 1 0 1 1 0 8 0 sigapl 432 176 0 166 2 0 2 2 0 8 0 futexpl 56 16 0 13 1 0 1 1 0 8 0 knotepl 112 5 0 0 1 0 1 1 0 8 0 kqueuepl 104 1 0 0 1 0 1 1 0 8 0 pipepl 112 122 0 111 2 1 1 1 0 8 0 fdescpl 424 177 0 166 2 0 2 2 0 8 0 filepl 120 845 0 796 2 0 2 2 0 8 0 lockfpl 104 8 0 6 2 1 1 1 0 8 0 lockfspl 48 4 0 3 2 1 1 1 0 8 0 sessionpl 112 18 0 9 1 0 1 1 0 8 0 pgrppl 48 18 0 9 1 0 1 1 0 8 0 ucredpl 96 47 0 40 1 0 1 1 0 8 0 zombiepl 144 166 0 166 2 1 1 1 0 8 1 processpl 864 191 0 166 4 0 4 4 0 8 0 procpl 632 198 0 166 3 0 3 3 0 8 0 sockpl 384 64 0 48 2 0 2 2 0 8 0 mcl4k 4096 10 0 10 1 0 1 1 0 8 1 mcl2k 2048 6106 0 6069 8 1 7 8 0 8 2 mtagpl 80 2 0 2 1 1 0 1 0 8 0 mbufpl 256 10399 0 10354 8 3 5 6 0 8 1 bufpl 256 2208 0 262 122 0 122 122 0 8 0 anonpl 16 18242 0 16762 8 2 6 7 0 62 0 amapchunkpl 152 490 0 441 2 0 2 2 0 158 0 amappl16 192 93 0 70 2 0 2 2 0 8 0 amappl14 176 36 0 32 1 0 1 1 0 8 0 amappl12 160 8 0 8 1 0 1 1 0 8 1 amappl11 152 41 0 30 1 0 1 1 0 8 0 amappl10 144 46 0 45 1 0 1 1 0 8 0 amappl9 136 376 0 374 1 0 1 1 0 8 0 amappl8 128 88 0 83 1 0 1 1 0 8 0 amappl7 120 13 0 12 1 0 1 1 0 8 0 amappl6 112 40 0 36 1 0 1 1 0 8 0 amappl5 104 167 0 158 1 0 1 1 0 8 0 amappl4 96 399 0 375 1 0 1 1 0 8 0 amappl3 88 148 0 137 1 0 1 1 0 8 0 amappl2 80 724 0 668 3 1 2 2 0 8 0 amappl1 72 12179 0 11741 16 6 10 16 0 8 0 amappl 80 371 0 345 1 0 1 1 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 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 177 0 166 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 177 0 166 1 0 1 1 0 8 0 vmmpekpl 168 5340 0 5326 1 0 1 1 0 8 0 vmmpepl 168 25952 0 25088 50 12 38 48 0 357 0 vmsppl 272 176 0 166 1 0 1 1 0 8 0 pdppl 4096 360 0 332 5 0 5 5 0 8 0 pvpl 32 71901 0 68781 30 4 26 26 0 265 0 pmappl 200 176 0 166 1 0 1 1 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 241 0 7 7 0 7 7 0 8 0 ddb>