panic: kernel diagnostic assertion "rn != NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/pipex.c", line 501 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8334145d) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff8337bc0d,ffffffff832ce345,1f5,ffffffff8333058a) at __assert+0x29 sys/kern/subr_prf.c:-1 pipex_unlink_session_locked(ffff8000ffffd4f0) at pipex_unlink_session_locked+0x402 pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline] pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:153 pppacclose(637e,41,2000,ffff80003c9a3cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335 spec_close(ffff80003c97fa20) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806b8450f8,41,fffffd8007bfb820,ffff80003c9a3cb0) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd806bb96978,ffff80003c9a3cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806bb96978,ffff80003c9a3cb0) at closef+0x190 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c9a3cb0) at fdfree+0x115 sys/kern/kern_descrip.c:1195 exit1(ffff80003c9a3cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c9a3cb0,ffff80003c97fd80,ffff80003c97fcd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c97fd70, count: 0 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 *cpu0: kernel diagnostic assertion "rn != NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/pipex.c", line 501 ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8334145d) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff8337bc0d,ffffffff832ce345,1f5,ffffffff8333058a) at __assert+0x29 sys/kern/subr_prf.c:-1 pipex_unlink_session_locked(ffff8000ffffd4f0) at pipex_unlink_session_locked+0x402 pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline] pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:153 pppacclose(637e,41,2000,ffff80003c9a3cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335 spec_close(ffff80003c97fa20) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806b8450f8,41,fffffd8007bfb820,ffff80003c9a3cb0) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd806bb96978,ffff80003c9a3cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806bb96978,ffff80003c9a3cb0) at closef+0x190 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c9a3cb0) at fdfree+0x115 sys/kern/kern_descrip.c:1195 exit1(ffff80003c9a3cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c9a3cb0,ffff80003c97fd80,ffff80003c97fcd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c97fd80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80003c97fd80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x763e1986e7e0, count: -16 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80003c97f800 rbx 0x1 rdx 0 rcx 0 rax 0xffff80003c9a3cb0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xb73af60004c0f1b r11 0xff93d5cc717ac7a9 r12 0 r13 0xffff8000ffffe180 r14 0 r15 0x1 rip 0xffffffff831265a5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c97f7f0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (syz-executor) tid=1283 pid=66818 tcnt=0 stat=onproc flags process=1018 proc=2000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0xffff80003c9a3cb0 scnt=-1 ecnt=1 forw=0xffffffffffffffff, list=0xffff80003c9a3250,0xffff80002a7f87f8 process=0xffff80003c9896e0 user=0xffff80003c97a000, vmspace=0xfffffd80761278b0 estcpu=36, cpticks=3, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 77362 82051 30552 0 2 0 syz-executor 1219 275992 46480 0 2 0 syz-executor 1219 15469 46480 0 2 0x4000000 syz-executor 54361 290273 36094 0 3 0x80 nanoslp syz-executor 54361 365404 36094 0 3 0x4000080 kqread syz-executor 54361 201733 36094 0 3 0x4000080 fsleep syz-executor 32495 93088 24572 0 3 0x3000 suspend syz-executor 32495 218120 24572 0 2 0x4081000 syz-executor 12102 219030 97301 0 2 0 syz-executor 12102 347127 97301 0 3 0x4000080 kqread syz-executor 12102 44472 97301 0 3 0x4000080 semwait syz-executor 12102 215543 97301 0 2 0x4000000 syz-executor 35918 266998 0 0 3 0x14200 bored sosplice 99754 239770 15999 0 3 0x82 wait syz-executor 46480 348801 15999 0 3 0x82 nanoslp syz-executor 7085 23267 15999 0 3 0x82 wait syz-executor 36094 53727 15999 0 3 0x82 nanoslp syz-executor 66264 8678 15999 0 3 0x82 nanoslp syz-executor 24572 256965 15999 0 3 0x82 nanoslp syz-executor 97301 145858 15999 0 3 0x82 nanoslp syz-executor 30552 211102 15999 0 3 0x82 nanoslp syz-executor 15999 355648 13849 0 3 0x82 kqread syz-executor 13849 263928 71476 0 3 0x10008a sigsusp ksh 71476 479183 75389 0 3 0x98 kqread sshd-session 75389 57413 10688 0 3 0x92 kqread sshd-session 21419 339522 1 0 3 0x100083 ttyin getty 10688 480389 1 0 3 0x88 kqread sshd 73700 40590 29965 73 3 0x1100090 kqread syslogd 29965 400443 1 0 3 0x100082 sbwait syslogd 7185 337470 1 0 3 0x100080 kqread resolvd 87204 353948 27247 77 2 0x100012 dhcpleased 44628 184169 27247 77 3 0x100092 kqread dhcpleased 27247 27895 1 0 3 0x80 kqread dhcpleased 42368 217159 0 0 3 0x14200 bored smr 65778 396324 0 0 2 0x14200 zerothread 50023 43871 0 0 3 0x14200 aiodoned aiodoned 38470 215476 0 0 3 0x14200 syncer update 585 273247 0 0 3 0x14200 cleaner cleaner 81923 16799 0 0 3 0x14200 reaper reaper 42284 358725 0 0 3 0x14200 pgdaemon pagedaemon 36091 146993 0 0 3 0x14200 bored viomb 53964 88566 0 0 3 0x40014200 acpi0 acpi0 70274 151169 0 0 3 0x14200 bored softnet7 72459 171448 0 0 3 0x14200 bored softnet6 1762 394889 0 0 3 0x14200 bored softnet5 803 427974 0 0 3 0x14200 bored softnet4 87455 251764 0 0 3 0x14200 bored softnet3 88198 405280 0 0 3 0x14200 bored softnet2 67834 518321 0 0 3 0x14200 bored softnet1 2019 250244 0 0 2 0x14200 softnet0 17814 6655 0 0 3 0x14200 smrbar systqmp 64613 206221 0 0 3 0x14200 bored systq 96305 329470 0 0 3 0x40014200 tmoslp softclock 85702 375589 0 0 3 0x40014200 idle0 1 103011 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 devbuf 10211 11058K 11264K 166960K 11405 0 pcb 17 12K 12K 166960K 49 0 rtable 187 7K 7K 166960K 330 0 pf 33 13K 14K 166960K 46 0 ifaddr 39 6K 7K 166960K 53 0 ifgroup 50 2K 2K 166960K 62 0 sysctl 1 1K 9K 166960K 6 0 counters 36 18K 18K 166960K 42 0 ioctlops 0 0K 4K 166960K 57 0 iov 0 0K 2K 166960K 7 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1408 88K 89K 166960K 1505 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 7 0 VM map 2 1K 1K 166960K 2 0 sem 7 0K 0K 166960K 9 0 dirhash 12 2K 2K 166960K 24 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 106K 166960K 244 0 sigio 0 0K 0K 166960K 2 0 proc 60 59K 124K 166960K 483 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 23 0 in_multi 84 6K 7K 166960K 108 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 2 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 235 1049K 1049K 166960K 235 0 exec 0 0K 1K 166960K 350 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 221 151K 160K 166960K 3568 0 UVM aobj 8 2K 2K 166960K 9 0 pinsyscall 39 78K 96K 166960K 1259 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 9 0 NDP 12 0K 2K 166960K 32 0 temp 41 8631K 8758K 166960K 8830 0 kqueue 16 23K 27K 166960K 40 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 47 0 44 1 0 1 1 0 8 0 rtentry 136 104 0 31 4 0 4 4 0 8 0 unpcb 144 339 0 316 1 0 1 1 0 8 0 syncache 336 4 0 4 1 0 1 1 0 8 1 tcpqe 32 9 0 9 1 0 1 1 0 8 1 tcpcb 736 39 0 33 2 0 2 2 0 8 0 arp 88 11 0 1 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 328 144 0 134 2 0 2 2 0 8 0 ip6q 72 1 0 0 1 0 1 1 0 8 0 ip6af 40 1 0 0 1 0 1 1 0 8 0 nd6 104 17 0 3 1 0 1 1 0 8 0 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1072 9 0 4 1 0 1 1 0 8 0 pfstkey 128 4 0 4 1 0 1 1 0 8 1 pfstate 384 2 0 2 1 0 1 1 0 8 1 pfrule 1344 1 0 1 1 0 1 1 0 8 1 rttmr 136 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 497 0 122 28 0 28 28 0 8 3 art_table 40 499 0 122 5 0 5 5 0 8 0 art_node 32 102 0 34 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 2 1 0 1 1 0 8 1 semapl 112 7 0 2 1 0 1 1 0 8 0 shmpl 112 6 0 1 1 0 1 1 0 8 0 dirhash 1024 25 0 8 3 0 3 3 0 8 0 dino2pl 256 1763 0 259 95 0 95 95 0 8 0 ffsino 256 1763 0 259 95 0 95 95 0 8 0 nchpl 144 2092 0 410 63 0 63 63 0 8 0 rtmask 32 2 0 0 1 0 1 1 0 8 0 uvmvnodes 80 1955 0 0 40 0 40 40 0 8 0 vnodes 216 1955 0 0 109 0 109 109 0 8 0 namei 1024 6595 0 6595 2 0 2 2 0 8 2 kstatmem 264 32 0 8 2 0 2 2 0 8 0 scxspl 216 7622 0 7622 8 0 8 8 1 8 8 plimitpl 152 80 0 63 1 0 1 1 0 8 0 sigapl 424 519 0 468 7 0 7 7 0 8 1 knotepl 120 7038 0 6987 9 0 9 9 0 8 7 kqueuepl 184 55 0 40 1 0 1 1 0 8 0 pipepl 304 105 0 75 3 0 3 3 0 8 0 fdescpl 448 498 0 468 5 0 5 5 0 8 1 filepl 120 2215 0 1979 10 0 10 10 0 8 2 lockfpl 104 126 0 124 1 0 1 1 0 8 0 lockfspl 48 30 0 28 1 0 1 1 0 8 0 sessionpl 144 21 0 13 1 0 1 1 0 8 0 pgrppl 48 32 0 16 1 0 1 1 0 8 0 ucredpl 104 269 0 256 1 0 1 1 0 8 0 zombiepl 144 472 0 468 1 0 1 1 0 8 0 processpl 1168 519 0 468 5 0 5 5 0 8 1 procpl 664 700 0 642 6 0 6 6 0 8 0 sosppl 168 2 0 2 1 0 1 1 0 8 1 sockpl 552 532 0 496 4 0 4 4 0 8 0 mcl64k 65536 5 0 5 1 0 1 1 0 8 1 mcl8k 8192 6 0 6 1 0 1 1 0 8 1 mcl4k 4096 2592 0 2542 15 0 15 15 0 8 8 mcl2k 2048 323 0 319 1 0 1 1 0 8 0 mtagpl 96 5 0 4 1 0 1 1 0 8 0 mbufpl 256 5104 0 4968 10 0 10 10 0 8 0 bufpl 280 3045 0 116 210 0 210 210 0 8 0 anonpl 24 78538 0 75352 23 0 23 23 0 187 3 amapchunkpl 152 10297 0 9830 21 0 21 21 0 158 1 amappl16 200 881 0 853 3 0 3 3 0 8 1 amappl15 192 6 0 5 1 0 1 1 0 8 0 amappl14 184 101 0 91 1 0 1 1 0 8 0 amappl13 176 3 0 3 1 0 1 1 0 8 1 amappl12 168 1105 0 1076 3 0 3 3 0 8 1 amappl11 160 45 0 35 1 0 1 1 0 8 0 amappl10 152 4 0 3 1 0 1 1 0 8 0 amappl9 144 240 0 240 1 0 1 1 0 8 1 amappl8 136 49 0 48 1 0 1 1 0 8 0 amappl7 128 102 0 92 1 0 1 1 0 8 0 amappl6 120 168 0 164 1 0 1 1 0 8 0 amappl5 112 107 0 101 1 0 1 1 0 8 0 amappl4 104 259 0 244 1 0 1 1 0 8 0 amappl3 96 1798 0 1692 3 0 3 3 0 8 0 amappl2 88 634 0 573 2 0 2 2 0 8 0 amappl1 80 8254 0 7699 13 0 13 13 0 8 1 amappl 88 2926 0 2770 4 0 4 4 0 92 0 dma8192 8192 1 0 1 1 0 1 1 0 8 1 dma4096 4096 1 0 1 1 0 1 1 0 8 1 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 0 1 1 0 8 1 dma128 128 253 0 253 1 0 1 1 0 8 1 dma64 64 6 0 6 1 0 1 1 0 8 1 dma32 32 7 0 7 1 0 1 1 0 8 1 dma16 16 19 0 18 1 0 1 1 0 8 0 aobjpl 72 8 0 1 1 0 1 1 0 8 0 uaddrrnd 24 498 0 468 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 498 0 468 1 0 1 1 0 8 0 vmmpekpl 168 5457 0 5424 2 0 2 2 0 8 0 vmmpepl 168 36628 0 34750 83 0 83 83 0 357 0 vmsppl 368 497 0 468 4 0 4 4 0 8 1 rwobjpl 40 13698 0 10893 29 0 29 29 0 8 0 pdppl 4096 1003 0 936 97 30 67 83 0 8 0 pvpl 32 214663 0 205517 81 0 81 81 0 265 1 pmappl 216 497 0 468 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 371 0 30 11 0 11 11 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8334145d) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff8337bc0d,ffffffff832ce345,1f5,ffffffff8333058a) at __assert+0x29 sys/kern/subr_prf.c:-1 pipex_unlink_session_locked(ffff8000ffffd4f0) at pipex_unlink_session_locked+0x402 pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline] pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:153 pppacclose(637e,41,2000,ffff80003c9a3cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335 spec_close(ffff80003c97fa20) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806b8450f8,41,fffffd8007bfb820,ffff80003c9a3cb0) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd806bb96978,ffff80003c9a3cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806bb96978,ffff80003c9a3cb0) at closef+0x190 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c9a3cb0) at fdfree+0x115 sys/kern/kern_descrip.c:1195 exit1(ffff80003c9a3cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c9a3cb0,ffff80003c97fd80,ffff80003c97fcd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c97fd80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80003c97fd80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x763e1986e7e0, count: -16 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8334145d) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff8337bc0d,ffffffff832ce345,1f5,ffffffff8333058a) at __assert+0x29 sys/kern/subr_prf.c:-1 pipex_unlink_session_locked(ffff8000ffffd4f0) at pipex_unlink_session_locked+0x402 pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 pipex_rele_session sys/net/pipex.c:-1 [inline] pipex_destroy_all_sessions(ffff800001491000) at pipex_destroy_all_sessions+0xd9 sys/net/pipex.c:153 pppacclose(637e,41,2000,ffff80003c9a3cb0) at pppacclose+0x16f sys/net/if_pppx.c:1335 spec_close(ffff80003c97fa20) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806b8450f8,41,fffffd8007bfb820,ffff80003c9a3cb0) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806bb96978,ffff80003c9a3cb0) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd806bb96978,ffff80003c9a3cb0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806bb96978,ffff80003c9a3cb0) at closef+0x190 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c9a3cb0) at fdfree+0x115 sys/kern/kern_descrip.c:1195 exit1(ffff80003c9a3cb0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c9a3cb0,ffff80003c97fd80,ffff80003c97fcd0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c97fd80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80003c97fd80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x763e1986e7e0, count: -16