panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *383387 61674 0 0x2 0 0 syz-executor.1 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be10) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bde19,ffffffff8256e150,90,ffffffff8252298b) at __assert+0x25 sys/kern/subr_prf.c:161 uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:710 uvm_pagealloc(fffffd807f0160e8,8b9d9000,0,3) at uvm_pagealloc+0x1e8 sys/uvm/uvm_page.c:918 pmap_get_ptp(fffffd807f0160d8,1173b39e000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1183 pmap_enter(fffffd807f0160d8,1173b39e000,67011000,3,21) at pmap_enter+0x2a0 uvm_fault_upper(ffff8000230ddc00,ffff8000230ddc38,ffff8000230ddb00,0) at uvm_fault_upper+0x268 sys/uvm/uvm_fault.c:1047 uvm_fault(fffffd806c337450,1173b39e000,0,1) at uvm_fault+0x144 sys/uvm/uvm_fault.c:610 upageflttrap(ffff8000230ddd70,1173b39ef48) at upageflttrap+0x79 sys/arch/amd64/amd64/trap.c:181 usertrap(ffff8000230ddd70) at usertrap+0x198 sys/arch/amd64/amd64/trap.c:403 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffdb6c0, 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+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be10) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bde19,ffffffff8256e150,90,ffffffff8252298b) at __assert+0x25 sys/kern/subr_prf.c:161 uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:710 uvm_pagealloc(fffffd807f0160e8,8b9d9000,0,3) at uvm_pagealloc+0x1e8 sys/uvm/uvm_page.c:918 pmap_get_ptp(fffffd807f0160d8,1173b39e000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1183 pmap_enter(fffffd807f0160d8,1173b39e000,67011000,3,21) at pmap_enter+0x2a0 uvm_fault_upper(ffff8000230ddc00,ffff8000230ddc38,ffff8000230ddb00,0) at uvm_fault_upper+0x268 sys/uvm/uvm_fault.c:1047 uvm_fault(fffffd806c337450,1173b39e000,0,1) at uvm_fault+0x144 sys/uvm/uvm_fault.c:610 upageflttrap(ffff8000230ddd70,1173b39ef48) at upageflttrap+0x79 sys/arch/amd64/amd64/trap.c:181 usertrap(ffff8000230ddd70) at usertrap+0x198 sys/arch/amd64/amd64/trap.c:403 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffdb6c0, count: -12 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000230dd730 rbx 0 rdx 0 rcx 0 rax 0xffff80002160c540 r8 0x101010101010101 r9 0x8080808080808080 r10 0x16990dd0396f6e14 r11 0xc53678f622f6ba r12 0 r13 0x8b9d9000 __kernel_virt_to_phys+0xb9d9000 r14 0 r15 0x1 rip 0xffffffff821b71a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000230dd720 ss 0 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.1) pid=383387 stat=onproc flags process=2 proc=0 pri=32, usrpri=83, nice=20 forw=0xffffffffffffffff, list=0xffff80002160c2a0,0xffff80002162d280 process=0xffff800021620400 user=0xffff8000230d8000, vmspace=0xfffffd806c337450 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 31070 300186 87376 0 2 0 syz-executor.4 39162 435126 52191 0 2 0 syz-executor.3 36767 97562 90928 0 2 0 syz-executor.2 *61674 383387 23811 0 7 0x2 syz-executor.1 90928 116193 23811 0 2 0x482 syz-executor.2 87376 404289 23811 0 2 0x482 syz-executor.4 52191 214608 23811 0 2 0x482 syz-executor.3 26275 15638 1 0 3 0x100083 ttyin getty 24571 302775 23811 0 2 0x2 syz-executor.0 85161 463802 23811 0 3 0x2 biowait syz-executor.5 82109 5530 23811 0 2 0x2 syz-executor.6 15460 500280 23811 0 2 0x2 syz-executor.7 52934 220523 0 0 3 0x14280 nfsidl nfsio 36815 98802 0 0 3 0x14280 nfsidl nfsio 82505 157589 0 0 3 0x14280 nfsidl nfsio 97050 467958 0 0 3 0x14280 nfsidl nfsio 6202 516635 0 0 3 0x14280 nfsidl nfsio 29227 379428 0 0 3 0x14280 nfsidl nfsio 28853 158762 0 0 3 0x14280 nfsidl nfsio 34570 131805 0 0 3 0x14280 nfsidl nfsio 98974 417538 0 0 3 0x14280 nfsidl nfsio 52171 388648 0 0 3 0x14280 nfsidl nfsio 81001 293488 0 0 3 0x14280 nfsidl nfsio 5479 370735 0 0 3 0x14280 nfsidl nfsio 27759 321112 0 0 3 0x14280 nfsidl nfsio 72002 295515 0 0 3 0x14280 nfsidl nfsio 17361 178290 0 0 3 0x14280 nfsidl nfsio 13520 24137 0 0 3 0x14280 nfsidl nfsio 58533 177296 0 0 3 0x14280 nfsidl nfsio 50476 23039 0 0 3 0x14280 nfsidl nfsio 72379 397451 0 0 3 0x14280 nfsidl nfsio 98243 402618 0 0 3 0x14280 nfsidl nfsio 6979 390485 0 0 3 0x14200 bored sosplice 23811 246405 96856 0 2 0x2 syz-fuzzer 23811 229295 96856 0 2 0x4000482 syz-fuzzer 23811 364901 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 513824 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 460411 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 252493 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 150213 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 482877 96856 0 3 0x4000082 thrsleep syz-fuzzer 23811 344084 96856 0 3 0x4000082 thrsleep syz-fuzzer 96856 250196 11223 0 3 0x10008a sigsusp ksh 11223 502227 10553 0 2 0x12 sshd 10553 335070 1 0 3 0x88 kqread sshd 50286 71659 46759 73 3 0x100090 kqread syslogd 46759 495927 1 0 3 0x100082 netio syslogd 4533 352520 1 0 3 0x100080 kqread resolvd 48483 38234 16664 77 3 0x100092 kqread dhcpleased 99299 519311 16664 77 3 0x100092 kqread dhcpleased 16664 201144 1 0 3 0x80 kqread dhcpleased 67812 74269 0 0 3 0x14200 bored smr 41958 422838 0 0 2 0x14200 zerothread 14213 119418 0 0 3 0x14200 aiodoned aiodoned 7391 345930 0 0 3 0x14200 syncer update 29264 416884 0 0 3 0x14200 cleaner cleaner 46993 468423 0 0 3 0x14200 reaper reaper 80715 197377 0 0 3 0x14200 pgdaemon pagedaemon 5688 158712 0 0 3 0x14200 bored viomb 65402 490479 0 0 3 0x40014200 acpi0 acpi0 61915 410187 0 0 2 0x14200 softnet 27223 261674 0 0 3 0x14200 bored systqmp 65804 160054 0 0 3 0x14200 bored systq 14648 382978 0 0 3 0x40014200 bored softclock 72381 192488 0 0 3 0x40014200 idle0 1 5015 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 10205 6497K 7009K 78643K 22772 0 pcb 13 18K 20K 78643K 613 0 rtable 228 11K 12K 78643K 1836 0 ifaddr 92 20K 22K 78643K 4918 0 sysctl 2 0K 0K 78643K 6 0 counters 27 17K 17K 78643K 91 0 ioctlops 0 0K 4K 78643K 2443 0 iov 0 0K 16K 78643K 653 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1333 83K 84K 78643K 4242 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 34 0 VM map 2 0K 0K 78643K 2 0 sem 12 0K 1K 78643K 433 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 13 45K 77K 78643K 4780 0 sigio 0 0K 0K 78643K 42 0 proc 58 55K 71K 78643K 1022 0 subproc 104 6K 6K 78643K 286 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 444 0 in_multi 92 6K 7K 78643K 429 0 ether_multi 1 0K 0K 78643K 40 0 mrt 0 0K 0K 78643K 32 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 247 1102K 1102K 78643K 247 0 exec 0 0K 2K 78643K 1485 0 pfkey data 0 0K 1K 78643K 3 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 317 138K 167K 78643K 58894 0 UVM aobj 129 4K 4K 78643K 130 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 155 0 NDP 12 0K 1K 78643K 136 0 temp 139 4715K 4793K 78643K 51655 0 kqueue 12 18K 26K 78643K 239 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 382 0 379 7 4 3 3 0 8 2 rtentry 112 388 0 295 4 1 3 4 0 8 0 unpcb 136 2640 0 2627 30 29 1 7 0 8 0 syncache 296 13 0 13 3 3 0 1 0 8 0 tcpqe 32 23 0 23 1 1 0 1 0 8 0 tcpcb 736 1323 0 1319 51 44 7 19 0 8 6 arp 88 46 0 28 1 0 1 1 0 8 0 ipq 40 9 0 9 3 3 0 1 0 8 0 ipqe 40 30 0 30 3 3 0 1 0 8 0 inpcb 304 3059 0 3052 49 43 6 12 0 8 5 rttmr 72 14 0 14 4 4 0 1 0 8 0 nd6 48 95 0 71 1 0 1 1 0 8 0 pkpcb 40 16 0 16 3 3 0 1 0 8 0 kcovpl 48 22 0 14 1 0 1 1 0 8 0 ppxss 1152 26 0 26 5 5 0 1 0 8 0 pfstscr 40 18 0 18 3 3 0 1 0 8 0 pfosfp 40 5 0 4 2 1 1 1 0 8 0 pfosfpen 112 5 0 4 2 1 1 1 0 8 0 pfrktable 1344 318 0 309 2 1 1 2 0 8 0 pftag 88 4 0 0 1 0 1 1 0 8 0 pfqueue 264 1 0 1 1 1 0 1 0 8 0 pfstitem 24 8 0 8 3 3 0 1 0 8 0 pfstkey 112 30 0 30 3 3 0 1 0 8 0 pfstate 320 15 0 15 3 3 0 1 0 8 0 pfrule 1360 1651 0 1613 5 1 4 4 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1384 0 963 41 12 29 32 0 8 2 art_table 32 1385 0 963 5 1 4 5 0 8 0 art_node 16 320 0 238 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 431 0 421 1 0 1 1 0 8 0 shmpl 112 127 0 1 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 7488 0 5918 99 0 99 99 0 8 0 ffsino 240 7488 0 5918 93 0 93 93 0 8 0 nchpl 144 13951 0 12338 62 0 62 62 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 224 5926 0 0 349 0 349 349 0 8 0 namei 1024 49248 0 49247 2 1 1 2 0 8 0 vcpupl 1984 68 0 1 9 0 9 9 0 8 0 vmpool 528 82 0 15 5 0 5 5 0 8 0 pfiaddrpl 120 135 0 120 1 0 1 1 0 8 0 scsiplug 72 3 0 3 1 1 0 1 0 8 0 scxspl 216 40995 0 40994 16 15 1 8 0 8 0 plimitpl 152 198 0 184 1 0 1 1 0 8 0 sigapl 424 5046 0 4988 9 1 8 8 0 8 0 futexpl 64 47982 0 47982 1 0 1 1 0 8 1 knotepl 120 47526 0 47445 10 3 7 10 0 8 4 kqueuepl 184 1311 0 1303 23 20 3 4 0 8 2 pipepl 304 9554 0 9526 73 63 10 17 0 8 7 fdescpl 432 5012 0 4988 4 0 4 4 0 8 0 filepl 120 46225 0 45991 61 45 16 19 0 8 8 lockfpl 104 1152 0 1150 4 2 2 2 0 8 1 lockfspl 48 401 0 399 1 0 1 1 0 8 0 sessionpl 144 37 0 21 1 0 1 1 0 8 0 pgrppl 48 40 0 24 1 0 1 1 0 8 0 ucredpl 96 3097 0 3074 1 0 1 1 0 8 0 zombiepl 144 4988 0 4988 1 0 1 1 0 8 1 processpl 1000 5046 0 4988 8 0 8 8 0 8 0 procpl 672 11944 0 11878 12 4 8 8 0 8 0 sosppl 168 30 0 30 7 7 0 1 0 8 0 sockpl 448 6098 0 6075 132 121 11 25 0 8 8 mcl64k 65536 104 0 104 8 7 1 1 0 8 1 mcl16k 16384 33 0 33 10 9 1 1 0 8 1 mcl12k 12288 204 0 204 8 8 0 1 0 8 0 mcl9k 9216 57 0 57 9 8 1 1 0 8 1 mcl8k 8192 259 0 259 5 4 1 1 0 8 1 mcl4k 4096 497 0 496 3 2 1 1 0 8 0 mcl2k2 2112 41 0 41 10 9 1 1 0 8 1 mcl2k 2048 82700 0 82648 17 8 9 10 0 8 1 mtagpl 96 2251 0 1596 23 6 17 17 0 8 1 mbufpl 256 158433 0 157564 95 34 61 70 0 8 6 bufpl 288 12306 0 5897 459 0 459 459 0 8 0 anonpl 24 1371443 0 1353591 232 87 145 167 0 188 22 amapchunkpl 152 149031 0 148359 80 44 36 46 0 158 2 amappl16 200 15358 0 14751 96 50 46 58 0 8 12 amappl15 192 725 0 718 1 0 1 1 0 8 0 amappl14 184 355 0 349 1 0 1 1 0 8 0 amappl13 176 968 0 964 1 0 1 1 0 8 0 amappl12 168 75 0 70 2 1 1 1 0 8 0 amappl11 160 1061 0 1048 1 0 1 1 0 8 0 amappl10 152 494 0 491 1 0 1 1 0 8 0 amappl9 144 741 0 736 1 0 1 1 0 8 0 amappl8 136 2096 0 1997 4 0 4 4 0 8 0 amappl7 128 1350 0 1338 1 0 1 1 0 8 0 amappl6 120 538 0 515 2 1 1 2 0 8 0 amappl5 112 3449 0 3437 1 0 1 1 0 8 0 amappl4 104 3358 0 3327 2 1 1 2 0 8 0 amappl3 96 1063 0 1049 1 0 1 1 0 8 0 amappl2 88 1619 0 1571 3 1 2 3 0 8 0 amappl1 80 90420 0 89944 20 7 13 18 0 8 0 amappl 88 58089 0 57898 10 3 7 7 0 92 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 72 129 0 1 3 0 3 3 0 8 0 uaddrrnd 24 5094 0 5003 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5094 0 5003 1 0 1 1 0 8 0 vmmpekpl 168 71451 0 71401 3 0 3 3 0 8 0 vmmpepl 168 454837 0 452498 192 57 135 144 0 357 13 vmsppl 272 5093 0 5003 9 2 7 7 0 8 0 rwobjpl 24 113215 0 105666 50 2 48 50 0 8 0 pdppl 4096 10194 0 10073 372 242 130 133 0 8 9 pvpl 32 2333843 0 2312041 380 148 232 261 0 265 31 pmappl 216 5093 0 5003 6 0 6 6 0 8 0 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 1408 0 489 27 0 27 27 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be10) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bde19,ffffffff8256e150,90,ffffffff8252298b) at __assert+0x25 sys/kern/subr_prf.c:161 uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:710 uvm_pagealloc(fffffd807f0160e8,8b9d9000,0,3) at uvm_pagealloc+0x1e8 sys/uvm/uvm_page.c:918 pmap_get_ptp(fffffd807f0160d8,1173b39e000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1183 pmap_enter(fffffd807f0160d8,1173b39e000,67011000,3,21) at pmap_enter+0x2a0 uvm_fault_upper(ffff8000230ddc00,ffff8000230ddc38,ffff8000230ddb00,0) at uvm_fault_upper+0x268 sys/uvm/uvm_fault.c:1047 uvm_fault(fffffd806c337450,1173b39e000,0,1) at uvm_fault+0x144 sys/uvm/uvm_fault.c:610 upageflttrap(ffff8000230ddd70,1173b39ef48) at upageflttrap+0x79 sys/arch/amd64/amd64/trap.c:181 usertrap(ffff8000230ddd70) at usertrap+0x198 sys/arch/amd64/amd64/trap.c:403 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffdb6c0, count: -12 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be10) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bde19,ffffffff8256e150,90,ffffffff8252298b) at __assert+0x25 sys/kern/subr_prf.c:161 uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 uvm_pageinsert sys/uvm/uvm_page.c:138 [inline] uvm_pagealloc_pg(fffffd800676e480,fffffd807f0160e8,8b9d9000,0) at uvm_pagealloc_pg+0x427 sys/uvm/uvm_page.c:710 uvm_pagealloc(fffffd807f0160e8,8b9d9000,0,3) at uvm_pagealloc+0x1e8 sys/uvm/uvm_page.c:918 pmap_get_ptp(fffffd807f0160d8,1173b39e000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1183 pmap_enter(fffffd807f0160d8,1173b39e000,67011000,3,21) at pmap_enter+0x2a0 uvm_fault_upper(ffff8000230ddc00,ffff8000230ddc38,ffff8000230ddb00,0) at uvm_fault_upper+0x268 sys/uvm/uvm_fault.c:1047 uvm_fault(fffffd806c337450,1173b39e000,0,1) at uvm_fault+0x144 sys/uvm/uvm_fault.c:610 upageflttrap(ffff8000230ddd70,1173b39ef48) at upageflttrap+0x79 sys/arch/amd64/amd64/trap.c:181 usertrap(ffff8000230ddd70) at usertrap+0x198 sys/arch/amd64/amd64/trap.c:403 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffdb6c0, count: -12