panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *475069 19580 0 0x2 0 0 syz-executor.3 db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff829263ed) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff828de74a,ffffffff8282fe3c,90,ffffffff828e45a9) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80067f4e00,fffffd8067bf1550,1cf58000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd8067bf1550,1cf58000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8067bf1520,73d6091dd000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215 pmap_enter(fffffd8067bf1520,73d6091dd000,74a58000,3,20) at pmap_enter+0x2b0 uvm_fault_upper_lookup(ffff800030f75250,ffff800030f75288,ffff800030f75150,ffff800030f751d0) at uvm_fault_upper_lookup+0x291 uvm_fault(fffffd8074bdc700,73d6091de000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800030f753d0,73d6091de0c0) at upageflttrap+0x85 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800030f753d0) at usertrap+0x20e sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d6091de0e0, 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+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff829263ed) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff828de74a,ffffffff8282fe3c,90,ffffffff828e45a9) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80067f4e00,fffffd8067bf1550,1cf58000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd8067bf1550,1cf58000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8067bf1520,73d6091dd000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215 pmap_enter(fffffd8067bf1520,73d6091dd000,74a58000,3,20) at pmap_enter+0x2b0 uvm_fault_upper_lookup(ffff800030f75250,ffff800030f75288,ffff800030f75150,ffff800030f751d0) at uvm_fault_upper_lookup+0x291 uvm_fault(fffffd8074bdc700,73d6091de000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800030f753d0,73d6091de0c0) at upageflttrap+0x85 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800030f753d0) at usertrap+0x20e sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d6091de0e0, count: -12 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800030f74d60 rbx 0x1cf58000 rdx 0 rcx 0 rax 0xffff80002a6ae2a8 r8 0x101010101010101 r9 0x8080808080808080 r10 0xe0be990e3355be82 r11 0xe470535c7f1eaddd r12 0 r13 0x1cf58000 r14 0 r15 0x1 rip 0xffffffff8275e6bc db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800030f74d50 ss 0 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (syz-executor.3) tid=475069 pid=19580 tcnt=1 stat=onproc flags process=2 proc=0 runpri=32, usrpri=57, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff80002a6742c8,0xffff80002a674ad0 process=0xffff800034389d68 user=0xffff800030f70000, vmspace=0xfffffd8074bdc700 estcpu=36, cpticks=2, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 30859 417864 92196 0 3 0x80 fsleep syz-executor.4 30859 440795 92196 0 3 0x4000000 smrbar syz-executor.4 27983 362105 65422 0 3 0x4081000 smrbar syz-executor.0 27983 146691 65422 0 3 0x4003000 suspend syz-executor.0 99832 373952 52244 0 3 0x80 fsleep syz-executor.1 99832 408215 52244 0 3 0x4000080 ttyin syz-executor.1 *19580 475069 73748 0 7 0x2 syz-executor.3 52244 375666 73748 0 3 0x82 nanoslp syz-executor.1 30412 396496 1 0 3 0x80 fsleep syz-executor.1 30412 333675 1 0 3 0x4000080 fsleep syz-executor.1 30412 424105 1 0 3 0x4000080 netio syz-executor.1 13618 326453 73748 0 3 0x82 nanoslp syz-executor.2 19455 77087 73748 0 2 0x2 syz-executor.7 65422 207933 73748 0 3 0x82 nanoslp syz-executor.0 70505 235709 73748 0 2 0x482 syz-executor.6 63016 446740 73748 0 3 0x82 nanoslp syz-executor.5 78760 387590 0 0 3 0x14280 nfsidl nfsio 94621 201855 0 0 3 0x14280 nfsidl nfsio 14648 342763 0 0 3 0x14280 nfsidl nfsio 19487 68568 0 0 3 0x14280 nfsidl nfsio 68166 122621 0 0 3 0x14280 nfsidl nfsio 9289 389651 0 0 3 0x14280 nfsidl nfsio 66309 205943 0 0 3 0x14280 nfsidl nfsio 24315 487708 0 0 3 0x14280 nfsidl nfsio 23345 151264 0 0 3 0x14280 nfsidl nfsio 44030 31474 0 0 3 0x14280 nfsidl nfsio 56723 322149 0 0 3 0x14280 nfsidl nfsio 78073 218513 0 0 3 0x14280 nfsidl nfsio 63134 27986 0 0 3 0x14280 nfsidl nfsio 94548 30435 0 0 3 0x14280 nfsidl nfsio 31453 40573 0 0 3 0x14280 nfsidl nfsio 10552 34258 0 0 3 0x14280 nfsidl nfsio 23966 409735 0 0 3 0x14280 nfsidl nfsio 30843 261166 0 0 3 0x14280 nfsidl nfsio 75404 6347 0 0 3 0x14280 nfsidl nfsio 8486 157221 0 0 3 0x14280 nfsidl nfsio 51371 85699 0 0 3 0x14200 bored sosplice 92196 437160 73748 0 3 0x82 nanoslp syz-executor.4 73748 240787 88556 0 3 0x1a000082 thrsleep syz-fuzzer 73748 423577 88556 0 2 0x1e000082 syz-fuzzer 73748 330048 88556 0 3 0x1e000082 wait syz-fuzzer 73748 230434 88556 0 3 0x1e000082 thrsleep syz-fuzzer 73748 237346 88556 0 3 0x1e000082 wait syz-fuzzer 73748 193080 88556 0 3 0x1e000082 wait syz-fuzzer 73748 435488 88556 0 3 0x1e000082 wait syz-fuzzer 73748 263439 88556 0 2 0x1e000002 syz-fuzzer 73748 313064 88556 0 3 0x1e000082 wait syz-fuzzer 73748 441463 88556 0 3 0x1e000082 wait syz-fuzzer 73748 238567 88556 0 3 0x1e000082 thrsleep syz-fuzzer 73748 394871 88556 0 3 0x1e000082 thrsleep syz-fuzzer 73748 396263 88556 0 3 0x1e000082 wait syz-fuzzer 73748 379036 88556 0 3 0x1e000082 wait syz-fuzzer 88556 25676 26003 0 3 0x810008a sigsusp ksh 26003 414394 44354 0 3 0x1800009a kqread sshd 49724 281398 1 0 3 0x18100083 ttyin getty 44354 408954 1 0 3 0x18000088 kqread sshd 74413 333564 75090 73 3 0x19100090 kqread syslogd 75090 141068 1 0 3 0x18100082 netio syslogd 99534 76655 1 0 3 0x18100080 kqread resolvd 28755 162731 31492 77 3 0x18100092 kqread dhcpleased 61390 308026 31492 77 3 0x18100092 kqread dhcpleased 31492 137678 1 0 3 0x18000080 kqread dhcpleased 33108 350778 0 0 3 0x14200 bored smr 50704 41469 0 0 3 0x14200 pgzero zerothread 50399 210037 0 0 3 0x14200 aiodoned aiodoned 34128 271410 0 0 3 0x14200 syncer update 96850 121857 0 0 3 0x14200 cleaner cleaner 38540 160107 0 0 3 0x14200 reaper reaper 22265 402673 0 0 3 0x14200 pgdaemon pagedaemon 64586 116372 0 0 3 0x14200 bored viomb 909 230772 0 0 3 0x40014200 acpi0 acpi0 84504 223982 0 0 3 0x14200 bored softnet3 65606 130557 0 0 3 0x14200 bored softnet2 1209 318375 0 0 3 0x14200 bored softnet1 38906 371762 0 0 3 0x14200 bored softnet0 57300 56833 0 0 3 0x14200 bored systqmp 57423 240199 0 0 3 0x14200 bored systq 83683 306980 0 0 3 0x40014200 tmoslp softclock 48263 113527 0 0 3 0x40014200 idle0 1 151687 0 0 3 0x8000082 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 10203 6420K 14728K 166960K 19766 0 pcb 15 14K 15K 166960K 246 0 rtable 233 7K 7K 166960K 1386 0 pf 34 9K 9K 166960K 239 0 ifaddr 44 12K 12K 166960K 184 0 ifgroup 57 2K 2K 166960K 386 0 sysctl 2 0K 0K 166960K 2 0 counters 32 17K 17K 166960K 115 0 ioctlops 0 0K 2K 166960K 208 0 iov 1 2K 20K 166960K 447 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1510 95K 95K 166960K 3992 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 78 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 1108 0 dirhash 12 2K 2K 166960K 42 0 ACPI 1697 195K 286K 166960K 12548 0 file desc 15 53K 69K 166960K 3964 0 sigio 0 0K 0K 166960K 95 0 proc 57 59K 75K 166960K 1010 0 subproc 117 7K 7K 166960K 273 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 544 0 in_multi 95 7K 7K 166960K 299 0 ether_multi 1 0K 0K 166960K 6 0 mrt 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 223 996K 996K 166960K 223 0 exec 0 0K 1K 166960K 948 0 pfkey data 0 0K 0K 166960K 70 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 373 159K 160K 166960K 38890 0 UVM aobj 131 4K 4K 166960K 136 0 pinsyscall 22 44K 100K 166960K 1621 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 143 0 NDP 13 0K 2K 166960K 141 0 temp 79 6806K 6932K 166960K 47276 0 kqueue 12 18K 27K 166960K 284 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 120 321 0 316 3 0 3 3 0 8 2 rtentry 112 532 0 424 4 0 4 4 0 8 0 unpcb 144 3391 0 3376 10 1 9 10 0 8 8 syncache 336 24 0 24 1 0 1 1 0 8 1 tcpqe 32 142 0 142 1 0 1 1 0 8 1 tcpcb 808 1188 0 1183 9 0 9 9 0 8 8 arp 88 132 0 114 1 0 1 1 0 8 0 ipq 40 6 0 6 1 0 1 1 0 8 1 ipqe 40 63 0 63 1 0 1 1 0 8 1 inpcb 360 2673 0 2665 12 3 9 12 0 8 8 nd6 104 69 0 46 1 0 1 1 0 8 0 pkpcb 40 74 0 74 1 0 1 1 0 8 1 kcovpl 48 21 0 12 1 0 1 1 0 8 0 ppxss 1072 22 0 21 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1284 0 829 32 2 30 30 0 8 1 art_table 32 1285 0 829 4 0 4 4 0 8 0 art_node 16 527 0 429 1 0 1 1 0 8 0 sysvmsgpl 40 17 0 16 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 1106 0 1096 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 37 0 20 3 0 3 3 0 8 0 dino2pl 256 6646 0 5119 96 0 96 96 0 8 0 ffsino 240 6646 0 5119 91 0 91 91 0 8 0 nchpl 144 11995 0 10263 66 0 66 66 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 43062 0 43062 2 0 2 2 0 8 2 vcpupl 2048 18 0 1 3 0 3 3 0 8 0 vmpool 664 21 0 4 2 0 2 2 0 8 0 kstatmem 264 192 0 166 2 0 2 2 0 8 0 scxspl 216 38928 0 38928 8 0 8 8 1 8 8 plimitpl 152 602 0 585 1 0 1 1 0 8 0 sigapl 424 4317 0 4251 8 0 8 8 0 8 0 futexpl 64 37017 0 37013 1 0 1 1 0 8 0 knotepl 120 47448 0 47366 11 0 11 11 0 8 7 kqueuepl 184 614 0 606 4 0 4 4 0 8 3 pipepl 288 755 0 726 7 0 7 7 0 8 4 fdescpl 432 4219 0 4193 4 0 4 4 0 8 0 filepl 120 26477 0 26218 16 0 16 16 0 8 7 lockfpl 104 1481 0 1479 2 0 2 2 0 8 1 lockfspl 48 408 0 406 1 0 1 1 0 8 0 sessionpl 144 36 0 19 1 0 1 1 0 8 0 pgrppl 48 85 0 68 1 0 1 1 0 8 0 ucredpl 104 3497 0 3487 1 0 1 1 0 8 0 zombiepl 144 4256 0 4251 1 0 1 1 0 8 0 processpl 1072 4317 0 4251 5 0 5 5 0 8 0 procpl 680 10444 0 10359 9 0 9 9 0 8 1 sosppl 168 29 0 29 1 0 1 1 0 8 1 sockpl 488 6460 0 6432 120 108 12 35 0 8 8 mcl64k 65536 141 0 141 1 0 1 1 0 8 1 mcl16k 16384 93 0 93 1 0 1 1 0 8 1 mcl12k 12288 178 0 178 1 0 1 1 0 8 1 mcl9k 9216 132 0 132 1 0 1 1 0 8 1 mcl8k 8192 384 0 383 1 0 1 1 0 8 0 mcl4k 4096 526 0 526 1 0 1 1 0 8 1 mcl2k2 2112 27 0 27 1 0 1 1 0 8 1 mcl2k 2048 77263 0 77217 33 19 14 28 0 8 7 mtagpl 96 1069 0 838 11 0 11 11 0 8 4 mbufpl 256 159872 0 159462 151 113 38 75 0 8 8 bufpl 280 11564 0 5218 454 0 454 454 0 8 0 anonpl 24 528903 0 517037 109 0 109 109 0 188 16 amapchunkpl 152 135648 0 134806 50 0 50 50 0 158 13 amappl16 200 11918 0 11474 47 13 34 37 0 8 8 amappl15 192 46 0 44 1 0 1 1 0 8 0 amappl14 184 188 0 178 2 0 2 2 0 8 1 amappl13 176 14 0 14 1 0 1 1 0 8 1 amappl12 168 5032 0 5004 2 0 2 2 0 8 0 amappl11 160 51 0 40 1 0 1 1 0 8 0 amappl10 152 47 0 37 1 0 1 1 0 8 0 amappl9 144 164 0 163 1 0 1 1 0 8 0 amappl8 136 274 0 206 3 0 3 3 0 8 0 amappl7 128 65 0 52 1 0 1 1 0 8 0 amappl6 120 512 0 488 2 0 2 2 0 8 1 amappl5 112 278 0 266 1 0 1 1 0 8 0 amappl4 104 657 0 624 2 0 2 2 0 8 1 amappl3 96 24732 0 24652 3 0 3 3 0 8 0 amappl2 88 4845 0 4773 4 0 4 4 0 8 2 amappl1 80 24147 0 23650 22 2 20 22 0 8 8 amappl 88 38147 0 37919 6 0 6 6 0 92 0 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 18 0 17 1 0 1 1 0 8 0 aobjpl 72 135 0 5 3 0 3 3 0 8 0 uaddrrnd 24 4240 0 4197 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4240 0 4197 1 0 1 1 0 8 0 vmmpekpl 168 35583 0 35527 3 0 3 3 0 8 0 vmmpepl 168 272250 0 270044 124 0 124 124 0 357 16 vmsppl 352 4239 0 4197 5 0 5 5 0 8 0 rwobjpl 24 75327 0 67794 47 0 47 47 0 8 0 pdppl 4096 8486 0 8411 272 192 80 83 0 8 5 pvpl 32 1339795 0 1322447 356 10 346 356 0 265 182 pmappl 216 4239 0 4197 3 0 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 717 0 326 13 0 13 13 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff829263ed) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff828de74a,ffffffff8282fe3c,90,ffffffff828e45a9) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80067f4e00,fffffd8067bf1550,1cf58000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd8067bf1550,1cf58000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8067bf1520,73d6091dd000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215 pmap_enter(fffffd8067bf1520,73d6091dd000,74a58000,3,20) at pmap_enter+0x2b0 uvm_fault_upper_lookup(ffff800030f75250,ffff800030f75288,ffff800030f75150,ffff800030f751d0) at uvm_fault_upper_lookup+0x291 uvm_fault(fffffd8074bdc700,73d6091de000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800030f753d0,73d6091de0c0) at upageflttrap+0x85 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800030f753d0) at usertrap+0x20e sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d6091de0e0, count: -12 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff829263ed) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff828de74a,ffffffff8282fe3c,90,ffffffff828e45a9) at __assert+0x29 sys/kern/subr_prf.c:157 uvm_pagealloc_pg(fffffd80067f4e00,fffffd8067bf1550,1cf58000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd8067bf1550,1cf58000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917 pmap_get_ptp(fffffd8067bf1520,73d6091dd000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215 pmap_enter(fffffd8067bf1520,73d6091dd000,74a58000,3,20) at pmap_enter+0x2b0 uvm_fault_upper_lookup(ffff800030f75250,ffff800030f75288,ffff800030f75150,ffff800030f751d0) at uvm_fault_upper_lookup+0x291 uvm_fault(fffffd8074bdc700,73d6091de000,0,1) at uvm_fault+0x109 sys/uvm/uvm_fault.c:605 upageflttrap(ffff800030f753d0,73d6091de0c0) at upageflttrap+0x85 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff800030f753d0) at usertrap+0x20e sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x73d6091de0e0, count: -12