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 *113019 94202 0 0 0 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83376396) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff833b7011,ffffffff8339bf29,90,ffffffff8334df28) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd800701d500,fffffd806a234cc8,1b43aa000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806a234cc8,1b43aa000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806a234cb8,36875584000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806a234cb8,36875584000,6a131000,3,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_upper(ffff80003b50ef80,ffff80003b50efb8,ffff80003b50ee80) at uvm_fault_upper+0x474 sys/uvm/uvm_fault.c:1131 uvm_fault(fffffd806a251a28,36875584000,0,1) at uvm_fault+0x178 sys/uvm/uvm_fault.c:635 upageflttrap(ffff80003b50f120,36875584000) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80003b50f120) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:632 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d3cf2e6980, 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(ffffffff83376396) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff833b7011,ffffffff8339bf29,90,ffffffff8334df28) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd800701d500,fffffd806a234cc8,1b43aa000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806a234cc8,1b43aa000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806a234cb8,36875584000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806a234cb8,36875584000,6a131000,3,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_upper(ffff80003b50ef80,ffff80003b50efb8,ffff80003b50ee80) at uvm_fault_upper+0x474 sys/uvm/uvm_fault.c:1131 uvm_fault(fffffd806a251a28,36875584000,0,1) at uvm_fault+0x178 sys/uvm/uvm_fault.c:635 upageflttrap(ffff80003b50f120,36875584000) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80003b50f120) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:632 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d3cf2e6980, count: -12 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80003b50eaa0 rbx 0xfffffd800701d501 rdx 0 rcx 0 rax 0xffff80002a7b9768 r8 0x101010101010101 r9 0x8080808080808080 r10 0x7666c1b2d43b5b0f r11 0x972346b481558f6 r12 0 r13 0x1b43aa000 r14 0 r15 0x1 rip 0xffffffff820108a5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003b50ea90 ss 0 db_enter+0x25: addq $0x8,%rsp ddb> show proc PROC (syz-executor) tid=113019 pid=94202 tcnt=2 stat=onproc flags process=0 proc=0 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c983788,0xffff80002a7bc2c0 process=0xffff8000ffff9b18 user=0xffff80003b50a000, vmspace=0xfffffd806a251a28 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND *94202 113019 47695 0 7 0 syz-executor 94202 18005 47695 0 2 0x4000000 syz-executor 51151 405367 18190 0 3 0x80 fsleep syz-executor 51151 5805 18190 0 3 0x4000080 fifor syz-executor 54296 170152 625 0 3 0x80 nanoslp syz-executor 54296 511271 625 0 3 0x4000080 kqread syz-executor 54296 422132 625 0 3 0x4000080 fsleep syz-executor 32928 60946 80390 0 3 0x80 fsleep syz-executor 32928 16574 80390 0 3 0x4000080 sbwait syz-executor 41607 133225 35940 0 3 0x80 fsleep syz-executor 41607 128157 35940 0 3 0x4000080 fifor syz-executor 41607 7016 35940 0 3 0x4000080 fsleep syz-executor 39369 15778 43288 0 3 0x80 fsleep syz-executor 39369 487703 43288 0 3 0x4000080 sbwait syz-executor 39369 223163 43288 0 3 0x4000080 sbwait syz-executor 47695 361746 25091 0 3 0x82 nanoslp syz-executor 12486 112460 0 0 3 0x14280 nfsidl nfsio 74269 501309 0 0 3 0x14280 nfsidl nfsio 28240 478974 0 0 3 0x14280 nfsidl nfsio 10784 35348 0 0 3 0x14280 nfsidl nfsio 39992 248699 0 0 3 0x14280 nfsidl nfsio 45599 85603 0 0 3 0x14280 nfsidl nfsio 51206 104530 0 0 3 0x14280 nfsidl nfsio 47975 276737 0 0 3 0x14280 nfsidl nfsio 3921 430165 0 0 3 0x14280 nfsidl nfsio 50414 227103 0 0 3 0x14280 nfsidl nfsio 61799 500690 0 0 3 0x14280 nfsidl nfsio 98122 102114 0 0 3 0x14280 nfsidl nfsio 21091 236203 0 0 3 0x14280 nfsidl nfsio 87687 157622 0 0 3 0x14280 nfsidl nfsio 28360 99692 0 0 3 0x14280 nfsidl nfsio 67249 53861 0 0 3 0x14280 nfsidl nfsio 50303 496726 0 0 3 0x14280 nfsidl nfsio 38195 181029 0 0 3 0x14280 nfsidl nfsio 98674 32501 0 0 3 0x14280 nfsidl nfsio 66366 106854 0 0 3 0x14280 nfsidl nfsio 18190 58067 25091 0 3 0x82 nanoslp syz-executor 35940 270715 25091 0 3 0x82 nanoslp syz-executor 80390 334364 25091 0 3 0x82 nanoslp syz-executor 625 17542 25091 0 3 0x82 nanoslp syz-executor 43288 320345 25091 0 3 0x82 nanoslp syz-executor 45013 37019 25091 0 3 0x82 nanoslp syz-executor 80714 402719 25091 0 3 0x82 wait syz-executor 25091 177049 13200 0 3 0x82 kqread syz-executor 13200 123848 46387 0 3 0x10008a sigsusp ksh 46387 219954 31984 0 3 0x98 kqread sshd-session 31984 468325 24155 0 3 0x92 kqread sshd-session 19600 206780 1 0 3 0x100083 ttyopn getty 24155 299455 1 0 3 0x88 kqread sshd 73903 227025 31164 73 3 0x1100090 kqread syslogd 31164 445146 1 0 3 0x100082 sbwait syslogd 79177 456963 1 0 3 0x100080 kqread resolvd 13768 437500 30308 77 3 0x100092 kqread dhcpleased 39755 67634 30308 77 3 0x100092 kqread dhcpleased 30308 198957 1 0 3 0x80 kqread dhcpleased 71119 349614 0 0 3 0x14200 bored smr 92064 356576 0 0 2 0x14200 zerothread 73210 222876 0 0 3 0x14200 aiodoned aiodoned 9599 42043 0 0 3 0x14200 syncer update 2394 420197 0 0 3 0x14200 cleaner cleaner 29212 34402 0 0 3 0x14200 reaper reaper 16070 134336 0 0 3 0x14200 pgdaemon pagedaemon 28798 259374 0 0 3 0x14200 bored viomb 82463 5547 0 0 3 0x40014200 acpi0 acpi0 62807 492251 0 0 3 0x14200 bored softnet0 40034 490487 0 0 3 0x14200 bored systqmp 76409 256647 0 0 3 0x14200 bored systq 92944 489746 0 0 3 0x40014200 tmoslp softclock 27254 83655 0 0 3 0x40014200 idle0 1 207798 0 0 3 0x82 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 11063 12303K 13869K 166960K 14324 0 pcb 20 15K 17K 166960K 332 0 rtable 201 8K 9K 166960K 508 0 pf 37 14K 15K 166960K 115 0 ifaddr 38 6K 7K 166960K 95 0 ifgroup 58 2K 2K 166960K 164 0 sysctl 4 1K 9K 166960K 10 0 counters 35 18K 18K 166960K 83 0 ioctlops 0 0K 4K 166960K 180 0 iov 0 0K 20K 166960K 41 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1530 96K 96K 166960K 2342 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 13 0 VM map 2 1K 1K 166960K 2 0 sem 6 0K 0K 166960K 12 0 dirhash 12 2K 2K 166960K 33 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 240K 166960K 835 0 sigio 0 0K 0K 166960K 12 0 proc 60 59K 116K 166960K 568 0 subproc 72 4K 4K 166960K 81 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 94 0 in_multi 80 5K 7K 166960K 141 0 ether_multi 1 0K 0K 166960K 8 0 mrt 2 0K 0K 166960K 10 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 97 440K 440K 166960K 97 0 exec 0 0K 1K 166960K 475 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 235 152K 165K 166960K 9049 0 UVM aobj 20 8K 8K 166960K 23 0 pinsyscall 39 78K 94K 166960K 1916 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 48 0 NDP 14 0K 2K 166960K 65 0 temp 64 8677K 8741K 166960K 23858 0 kqueue 16 24K 30K 166960K 139 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 82 0 78 1 0 1 1 0 8 0 rtentry 136 143 0 65 4 0 4 4 0 8 0 unpcb 144 555 0 532 9 5 4 6 0 8 3 syncache 336 5 0 5 2 1 1 1 0 8 1 tcpcb 736 301 0 297 7 3 4 4 0 8 3 arp 96 21 0 7 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 328 945 0 937 10 3 7 7 0 8 6 ip6q 72 2 0 0 1 0 1 1 0 8 0 ip6af 40 1 0 0 1 0 1 1 0 8 0 nd6 112 34 0 14 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 1 0 1 0 8 0 kcovpl 48 9 0 1 1 0 1 1 0 8 0 ppxss 1072 35 0 35 2 1 1 1 0 8 1 pppxif 1384 7 0 7 2 1 1 1 0 8 1 pfrktable 1344 1 0 1 1 1 0 1 0 8 0 pfstitem 24 4 0 0 1 0 1 1 0 8 0 pfstkey 128 6 0 2 2 1 1 1 0 8 0 pfstate 384 3 0 1 2 1 1 1 0 8 0 pfrule 1360 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 1 0 0 1 0 1 1 0 8 0 art_heap4 256 612 0 239 30 4 26 29 0 8 2 art_table 40 613 0 239 5 0 5 5 0 8 0 art_node 32 143 0 73 1 0 1 1 0 8 0 sysvmsgpl 40 6 0 3 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 8 0 4 1 0 1 1 0 8 0 shmpl 112 17 0 2 1 0 1 1 0 8 0 dirhash 1024 31 0 14 3 0 3 3 0 8 0 dino2pl 256 2906 0 1408 95 0 95 95 0 8 0 ffsino 256 2906 0 1408 95 0 95 95 0 8 0 nchpl 144 3975 0 2280 64 0 64 64 0 8 0 rtmask 32 5 0 5 2 1 1 1 0 8 1 vnodes 216 3657 0 0 204 0 204 204 0 8 0 namei 1024 13380 0 13380 2 1 1 2 0 8 1 vcpupl 3904 3 0 1 1 0 1 1 0 8 0 vmpool 808 3 0 1 1 0 1 1 0 8 0 kstatmem 264 92 0 66 2 0 2 2 0 8 0 scsiplug 72 4 0 4 2 1 1 1 0 8 1 scxspl 216 15378 0 15378 9 1 8 8 1 8 8 plimitpl 152 204 0 188 1 0 1 1 0 8 0 sigapl 424 1129 0 1066 8 0 8 8 0 8 0 knotepl 120 36252 0 36198 22 12 10 14 0 8 8 kqueuepl 184 253 0 242 3 0 3 3 0 8 2 pipepl 304 198 0 171 5 0 5 5 0 8 2 fdescpl 448 1093 0 1063 5 1 4 5 0 8 0 filepl 120 6616 0 6389 13 3 10 11 0 8 2 lockfpl 104 224 0 221 1 0 1 1 0 8 0 lockfspl 48 102 0 99 1 0 1 1 0 8 0 sessionpl 144 22 0 14 1 0 1 1 0 8 0 pgrppl 48 39 0 23 1 0 1 1 0 8 0 ucredpl 104 1028 0 1017 1 0 1 1 0 8 0 zombiepl 144 1285 0 1283 1 0 1 1 0 8 0 processpl 1152 1129 0 1066 5 0 5 5 0 8 0 procpl 664 2192 0 2120 7 0 7 7 0 8 0 sosppl 176 5 0 5 2 1 1 1 0 8 1 sockpl 552 1640 0 1603 17 9 8 12 0 8 5 mcl64k 65536 41 0 41 2 1 1 1 0 8 1 mcl9k 9216 1 0 1 1 0 1 1 0 8 1 mcl8k 8192 15 0 15 2 1 1 1 0 8 1 mcl4k 4096 3378 0 3327 16 8 8 16 0 8 1 mcl2k 2048 1455 0 1449 6 4 2 5 0 8 0 mtagpl 96 38 0 18 1 0 1 1 0 8 0 mbufpl 256 13323 0 13150 78 61 17 74 0 8 4 bufpl 280 7233 0 1012 445 0 445 445 0 8 0 anonpl 24 167885 0 164574 62 17 45 49 0 187 11 amapchunkpl 152 28695 0 28194 31 3 28 28 0 158 7 amappl16 200 3302 0 3265 28 13 15 17 0 8 8 amappl15 192 20 0 20 1 1 0 1 0 8 0 amappl14 184 75 0 75 1 1 0 1 0 8 0 amappl13 176 416 0 415 1 0 1 1 0 8 0 amappl12 168 1436 0 1397 2 0 2 2 0 8 0 amappl11 160 3 0 3 1 1 0 1 0 8 0 amappl10 152 44 0 34 1 0 1 1 0 8 0 amappl9 144 256 0 256 1 1 0 1 0 8 0 amappl8 136 34 0 32 1 0 1 1 0 8 0 amappl7 128 79 0 78 1 0 1 1 0 8 0 amappl6 120 284 0 272 1 0 1 1 0 8 0 amappl5 112 69 0 59 1 0 1 1 0 8 0 amappl4 104 401 0 377 1 0 1 1 0 8 0 amappl3 96 5132 0 5037 3 0 3 3 0 8 0 amappl2 88 1210 0 1138 2 0 2 2 0 8 0 amappl1 80 11547 0 11014 12 1 11 12 0 8 0 amappl 88 8233 0 8066 4 0 4 4 0 92 0 uvmvnodes 80 120 0 0 3 0 3 3 0 8 0 dma16384 16384 1 0 1 1 1 0 1 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 22 0 3 1 0 1 1 0 8 0 uaddrrnd 24 1093 0 1063 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1093 0 1063 1 0 1 1 0 8 0 vmmpekpl 168 9812 0 9778 2 0 2 2 0 8 0 vmmpepl 168 74145 0 72310 96 5 91 91 0 357 7 vmsppl 368 1092 0 1063 4 1 3 4 0 8 0 rwobjpl 40 21373 0 20384 13 0 13 13 0 8 0 pdppl 4096 2199 0 2130 103 33 70 83 0 8 1 pvpl 32 468150 0 459362 140 26 114 125 0 265 26 pmappl 216 1095 0 1064 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 457 0 122 12 1 11 12 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(ffffffff83376396) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff833b7011,ffffffff8339bf29,90,ffffffff8334df28) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd800701d500,fffffd806a234cc8,1b43aa000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806a234cc8,1b43aa000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806a234cb8,36875584000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806a234cb8,36875584000,6a131000,3,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_upper(ffff80003b50ef80,ffff80003b50efb8,ffff80003b50ee80) at uvm_fault_upper+0x474 sys/uvm/uvm_fault.c:1131 uvm_fault(fffffd806a251a28,36875584000,0,1) at uvm_fault+0x178 sys/uvm/uvm_fault.c:635 upageflttrap(ffff80003b50f120,36875584000) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80003b50f120) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:632 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d3cf2e6980, 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(ffffffff83376396) at panic+0x1cf sys/kern/subr_prf.c:198 __assert(ffffffff833b7011,ffffffff8339bf29,90,ffffffff8334df28) at __assert+0x29 sys/kern/subr_prf.c:-1 uvm_pagealloc_pg(fffffd800701d500,fffffd806a234cc8,1b43aa000,0) at uvm_pagealloc_pg+0x54b sys/uvm/uvm_page.c:707 uvm_pagealloc(fffffd806a234cc8,1b43aa000,0,3) at uvm_pagealloc+0x252 sys/uvm/uvm_page.c:913 pmap_get_ptp(fffffd806a234cb8,36875584000) at pmap_get_ptp+0x1d0 sys/arch/amd64/amd64/pmap.c:-1 pmap_enter(fffffd806a234cb8,36875584000,6a131000,3,21) at pmap_enter+0x3a3 sys/arch/amd64/amd64/pmap.c:-1 uvm_fault_upper(ffff80003b50ef80,ffff80003b50efb8,ffff80003b50ee80) at uvm_fault_upper+0x474 sys/uvm/uvm_fault.c:1131 uvm_fault(fffffd806a251a28,36875584000,0,1) at uvm_fault+0x178 sys/uvm/uvm_fault.c:635 upageflttrap(ffff80003b50f120,36875584000) at upageflttrap+0xa0 sys/arch/amd64/amd64/trap.c:192 usertrap(ffff80003b50f120) at usertrap+0x413 sys/arch/amd64/amd64/trap.c:632 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d3cf2e6980, count: -12