panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 63051 17604 0 0x10 0 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834125e3) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff83452871,ffffffff83439e03,90,ffffffff833ecf93) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd8006c61380,fffffd806cfaae70,78050b000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806cfaae70,78050b000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806cfaae60,f00a17b8000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806cfaae60,f00a17b8000,7a3e9000,1,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_lower(ffff80002f0bee70,ffff80002f0beea8,ffff80002f0bedf0) at uvm_fault_lower+0x7a6 sys/uvm/uvm_fault.c:1504 uvm_fault(fffffd807dfad5d8,f00a17b8000,0,1) at uvm_fault+0x241 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff80002f0bf010,f00a17b804c) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80002f0bf010) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:640 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a0b3104bcd0, count: 3 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 "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834125e3) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff83452871,ffffffff83439e03,90,ffffffff833ecf93) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd8006c61380,fffffd806cfaae70,78050b000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806cfaae70,78050b000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806cfaae60,f00a17b8000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806cfaae60,f00a17b8000,7a3e9000,1,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_lower(ffff80002f0bee70,ffff80002f0beea8,ffff80002f0bedf0) at uvm_fault_lower+0x7a6 sys/uvm/uvm_fault.c:1504 uvm_fault(fffffd807dfad5d8,f00a17b8000,0,1) at uvm_fault+0x241 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff80002f0bf010,f00a17b804c) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80002f0bf010) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:640 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a0b3104bcd0, count: -12 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80002f0be980 rbx 0xfffffd8006c61301 rdx 0 rcx 0 rax 0xffff80002f0c1ca0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xa5782abee4c01c66 r11 0xd49cfcd36a950287 r12 0 r13 0x78050b000 r14 0 r15 0x1 rip 0xffffffff82154895 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002f0be970 ss 0 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (syz-executor) tid=63051 pid=17604 tcnt=3 stat=onproc flags process=10 proc=0 runpri=50, usrpri=50, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c9b4560,0xffff80002f0c0028 process=0xffff80003c9831a0 user=0xffff80002f0ba000, vmspace=0xfffffd807dfad5d8 estcpu=36, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 62675 286405 50103 0 2 0 syz-executor 62675 220897 50103 0 3 0x4000080 fsleep syz-executor *17604 63051 32177 0 7 0x10 syz-executor 17604 204751 32177 0 3 0x4000090 fsleep syz-executor 17604 510374 32177 0 3 0x4000090 fsleep syz-executor 44140 183948 0 0 3 0x14200 acct acct 52721 197486 80274 0 3 0x80 nanoslp syz-executor 52721 190387 80274 0 3 0x4000080 kqsel syz-executor 52721 131237 80274 0 3 0x4000080 fsleep syz-executor 15127 288060 23458 0 3 0x80 nanoslp syz-executor 15127 120100 23458 0 3 0x4000080 lockf syz-executor 15127 83853 23458 0 3 0x4000080 fsleep syz-executor 11456 486495 6963 0 3 0x80 nanoslp syz-executor 11456 301702 6963 0 3 0x4000080 kqread syz-executor 11456 186098 6963 0 3 0x4000080 fsleep syz-executor 50103 87322 99764 0 3 0x82 nanoslp syz-executor 23458 410415 99764 0 3 0x82 nanoslp syz-executor 32177 158354 99764 0 3 0x82 nanoslp syz-executor 65607 5524 99764 0 3 0x82 wait syz-executor 89881 107352 1 0 3 0x100083 ttyin getty 6963 143018 99764 0 3 0x82 nanoslp syz-executor 99590 287542 0 0 3 0x14280 nfsidl nfsio 73647 77951 0 0 3 0x14280 nfsidl nfsio 16397 381647 0 0 3 0x14280 nfsidl nfsio 99728 179076 0 0 3 0x14280 nfsidl nfsio 88332 388717 0 0 3 0x14280 nfsidl nfsio 91401 11068 0 0 3 0x14280 nfsidl nfsio 96675 30194 0 0 3 0x14280 nfsidl nfsio 14491 210090 0 0 3 0x14280 nfsidl nfsio 29592 288458 0 0 3 0x14280 nfsidl nfsio 93709 42590 0 0 3 0x14280 nfsidl nfsio 61148 295612 0 0 3 0x14280 nfsidl nfsio 88508 207414 0 0 3 0x14280 nfsidl nfsio 17796 29329 0 0 3 0x14280 nfsidl nfsio 93670 353120 0 0 3 0x14280 nfsidl nfsio 56313 30188 0 0 3 0x14280 nfsidl nfsio 69513 484057 0 0 3 0x14280 nfsidl nfsio 32304 450035 0 0 3 0x14280 nfsidl nfsio 50395 464890 0 0 3 0x14280 nfsidl nfsio 32621 384530 0 0 3 0x14280 nfsidl nfsio 48409 502080 0 0 3 0x14280 nfsidl nfsio 51323 180322 99764 0 3 0x82 nanoslp syz-executor 58945 366257 99764 0 3 0x82 nanoslp syz-executor 80274 111698 99764 0 3 0x82 nanoslp syz-executor 99764 433889 88415 0 3 0x82 kqread syz-executor 88415 517595 77189 0 3 0x10008a sigsusp ksh 77189 323981 38897 0 3 0x98 kqread sshd-session 38897 87468 17811 0 3 0x92 kqread sshd-session 17811 234857 1 0 3 0x88 kqread sshd 48298 498953 56121 73 3 0x1100090 kqread syslogd 56121 136834 1 0 3 0x100082 sbwait syslogd 18611 268879 1 0 3 0x100080 kqread resolvd 86518 412222 93529 77 3 0x100092 kqread dhcpleased 70928 475513 93529 77 3 0x100092 kqread dhcpleased 93529 95679 1 0 3 0x80 kqread dhcpleased 60694 455618 0 0 3 0x14200 bored smr 72861 410979 0 0 2 0x14200 zerothread 9112 395568 0 0 3 0x14200 aiodoned aiodoned 52132 244154 0 0 3 0x14200 syncer update 56053 415872 0 0 3 0x14200 cleaner cleaner 72414 495982 0 0 3 0x14200 reaper reaper 89424 145195 0 0 3 0x14200 pgdaemon pagedaemon 17929 274097 0 0 3 0x14200 bored viomb 72686 301453 0 0 3 0x40014200 acpi0 acpi0 26961 263598 0 0 3 0x14200 bored softnet0 74887 74456 0 0 3 0x14200 bored systqmp 3448 69591 0 0 3 0x14200 bored systq 26557 274115 0 0 3 0x40014200 tmoslp softclock 94015 326761 0 0 3 0x40014200 idle0 1 411918 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11076 12122K 12722K 166960K 13664 0 pcb 17 16K 25K 166960K 402 0 rtable 209 8K 9K 166960K 778 0 pf 41 14K 18K 166960K 179 0 ifaddr 41 6K 8K 166960K 146 0 ifgroup 65 2K 2K 166960K 223 0 sysctl 4 1K 9K 166960K 25 0 counters 39 18K 18K 166960K 116 0 ioctlops 0 0K 4K 166960K 333 0 iov 0 0K 16K 166960K 60 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1448 91K 92K 166960K 2670 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 13 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 1K 166960K 183 0 dirhash 12 2K 2K 166960K 33 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 240K 166960K 1412 0 sigio 0 0K 0K 166960K 18 0 proc 60 59K 83K 166960K 819 0 subproc 72 4K 4K 166960K 136 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 140 0 in_multi 77 5K 7K 166960K 228 0 ether_multi 1 0K 0K 166960K 5 0 mrt 1 0K 0K 166960K 35 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 193 864K 864K 166960K 193 0 exec 0 0K 1K 166960K 587 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 232 159K 176K 166960K 13587 0 UVM aobj 91 15K 17K 166960K 97 0 pinsyscall 39 78K 90K 166960K 2660 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 2K 166960K 149 0 NDP 15 0K 2K 166960K 93 0 temp 80 9076K 9147K 166960K 19334 0 kqueue 15 24K 34K 166960K 258 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 120 231 0 228 2 0 2 2 0 8 1 rtentry 136 233 0 156 4 0 4 4 0 8 0 unpcb 144 911 0 895 4 0 4 4 0 8 3 syncache 336 7 0 7 1 1 0 1 0 8 0 tcpqe 32 5 0 5 1 0 1 1 0 8 1 tcpcb 736 521 0 517 13 6 7 7 0 8 6 arp 96 34 0 19 1 0 1 1 0 8 0 ipq 40 4 0 1 1 0 1 1 0 8 0 ipqe 40 7 0 4 1 0 1 1 0 8 0 inpcb 328 1452 0 1444 15 8 7 10 0 8 5 ip6q 72 12 0 6 1 0 1 1 0 8 0 ip6af 40 23 0 15 1 0 1 1 0 8 0 nd6 112 53 0 37 1 0 1 1 0 8 0 pkpcb 40 3 0 3 2 1 1 1 0 8 1 kcovpl 48 15 0 7 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 1 0 1 0 8 0 ppxss 1072 55 0 52 2 1 1 1 0 8 0 pppxif 1384 15 0 14 2 1 1 1 0 8 0 pftag 88 2 0 0 1 0 1 1 0 8 0 pfrule 1360 6 0 6 2 1 1 1 0 8 1 rttmr 136 2 0 2 1 1 0 1 0 8 0 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 1087 0 736 31 3 28 31 0 8 5 art_table 40 1091 0 736 5 0 5 5 0 8 0 art_node 32 232 0 162 1 0 1 1 0 8 0 sysvmsgpl 40 21 0 11 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 178 0 168 1 0 1 1 0 8 0 shmpl 112 89 0 5 3 0 3 3 0 8 0 dirhash 1024 31 0 14 3 0 3 3 0 8 0 dino2pl 256 4083 0 2614 93 0 93 93 0 8 0 ffsino 256 4083 0 2614 93 0 93 93 0 8 0 nchpl 144 5879 0 4163 64 0 64 64 0 8 0 rtmask 32 2 0 1 1 0 1 1 0 8 0 vnodes 216 4801 0 0 267 0 267 267 0 8 0 namei 1024 20660 0 20660 2 1 1 1 0 8 1 vcpupl 3904 5 0 1 1 0 1 1 0 8 0 vmpool 808 5 0 1 1 0 1 1 0 8 0 kstatmem 264 126 0 96 3 0 3 3 0 8 0 scsiplug 72 9 0 9 2 1 1 1 0 8 1 scxspl 216 29147 0 29147 10 2 8 8 1 8 8 plimitpl 152 459 0 443 1 0 1 1 0 8 0 sigapl 424 1690 0 1626 8 0 8 8 0 8 0 knotepl 120 56581 0 56530 32 22 10 25 0 8 8 kqueuepl 184 362 0 350 1 0 1 1 0 8 0 pipepl 304 276 0 249 8 0 8 8 0 8 5 fdescpl 448 1652 0 1622 4 0 4 4 0 8 0 filepl 120 10941 0 10716 19 4 15 15 0 8 7 lockfpl 104 544 0 539 3 0 3 3 0 8 2 lockfspl 48 153 0 149 1 0 1 1 0 8 0 sessionpl 144 30 0 22 1 0 1 1 0 8 0 pgrppl 48 88 0 72 1 0 1 1 0 8 0 ucredpl 104 2362 0 2349 1 0 1 1 0 8 0 zombiepl 144 1629 0 1626 1 0 1 1 0 8 0 processpl 1152 1690 0 1626 5 0 5 5 0 8 0 procpl 664 3318 0 3245 7 0 7 7 0 8 0 sosppl 176 10 0 10 2 1 1 1 0 8 1 sockpl 552 2712 0 2685 17 7 10 10 0 8 7 mcl64k 65536 165 0 164 1 0 1 1 0 8 0 mcl16k 16384 34 0 34 2 1 1 1 0 8 1 mcl12k 12288 13 0 13 2 1 1 1 0 8 1 mcl9k 9216 5 0 5 2 1 1 1 0 8 1 mcl8k 8192 45 0 45 2 1 1 1 0 8 1 mcl4k 4096 4279 0 4225 15 6 9 14 0 8 1 mcl2k2 2112 1 0 1 1 0 1 1 0 8 1 mcl2k 2048 1535 0 1525 6 3 3 4 0 8 1 mtagpl 96 15 0 14 1 0 1 1 0 8 0 mbufpl 256 104292 0 104155 114 99 15 114 0 8 2 bufpl 280 11559 0 5345 445 0 445 445 0 8 1 anonpl 24 260210 0 256945 80 11 69 69 0 187 28 amapchunkpl 152 44339 0 43839 32 6 26 27 0 158 6 amappl16 200 5904 0 5868 40 23 17 28 0 8 8 amappl15 192 5 0 5 1 1 0 1 0 8 0 amappl14 184 493 0 492 1 0 1 1 0 8 0 amappl13 176 130 0 120 1 0 1 1 0 8 0 amappl12 168 1915 0 1886 2 0 2 2 0 8 0 amappl11 160 20 0 20 1 1 0 1 0 8 0 amappl10 152 71 0 61 1 0 1 1 0 8 0 amappl9 144 257 0 257 1 1 0 1 0 8 0 amappl8 136 131 0 130 1 0 1 1 0 8 0 amappl7 128 160 0 149 1 0 1 1 0 8 0 amappl6 120 276 0 274 1 0 1 1 0 8 0 amappl5 112 106 0 99 1 0 1 1 0 8 0 amappl4 104 308 0 293 1 0 1 1 0 8 0 amappl3 96 9144 0 9029 4 0 4 4 0 8 0 amappl2 88 598 0 537 2 0 2 2 0 8 0 amappl1 80 14560 0 14009 13 1 12 13 0 8 0 amappl 88 12599 0 12430 5 0 5 5 0 92 0 uvmvnodes 80 147 0 0 3 0 3 3 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 2 0 1 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 256 0 256 2 1 1 1 0 8 1 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 8 0 8 2 1 1 1 0 8 1 dma16 16 19 0 18 1 0 1 1 0 8 0 aobjpl 72 96 0 6 2 0 2 2 0 8 0 uaddrrnd 24 1652 0 1622 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1652 0 1622 1 0 1 1 0 8 0 vmmpekpl 168 13505 0 13461 3 0 3 3 0 8 0 vmmpepl 168 108579 0 106728 109 7 102 102 0 357 13 vmsppl 368 1651 0 1622 4 1 3 4 0 8 0 rwobjpl 40 29993 0 28898 18 1 17 17 0 8 2 pdppl 4096 3320 0 3250 109 39 70 76 0 8 0 pvpl 32 766407 0 757104 168 24 144 144 0 265 38 pmappl 216 1656 0 1623 2 0 2 2 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 504 0 165 13 2 11 13 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(ffffffff834125e3) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff83452871,ffffffff83439e03,90,ffffffff833ecf93) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd8006c61380,fffffd806cfaae70,78050b000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806cfaae70,78050b000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806cfaae60,f00a17b8000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806cfaae60,f00a17b8000,7a3e9000,1,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_lower(ffff80002f0bee70,ffff80002f0beea8,ffff80002f0bedf0) at uvm_fault_lower+0x7a6 sys/uvm/uvm_fault.c:1504 uvm_fault(fffffd807dfad5d8,f00a17b8000,0,1) at uvm_fault+0x241 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff80002f0bf010,f00a17b804c) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80002f0bf010) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:640 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a0b3104bcd0, count: -12 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834125e3) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff83452871,ffffffff83439e03,90,ffffffff833ecf93) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd8006c61380,fffffd806cfaae70,78050b000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806cfaae70,78050b000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806cfaae60,f00a17b8000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806cfaae60,f00a17b8000,7a3e9000,1,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_lower(ffff80002f0bee70,ffff80002f0beea8,ffff80002f0bedf0) at uvm_fault_lower+0x7a6 sys/uvm/uvm_fault.c:1504 uvm_fault(fffffd807dfad5d8,f00a17b8000,0,1) at uvm_fault+0x241 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff80002f0bf010,f00a17b804c) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80002f0bf010) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:640 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7a0b3104bcd0, count: -12