panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 140 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 308736 37704 0 0 0x4000080 0 syz-executor.0 *220704 7044 0 0x100003 0 1K getty db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 __assert(ffffffff82207803,ffffffff821a7b14,8c,ffffffff82196f2c) at __assert+0x2b sys/kern/subr_prf.c:154 uvm_pagealloc(fffffd8062dbaa30,faf91f000,0,3) at uvm_pagealloc+0x476 sys/uvm/uvm_page.c:140 pmap_get_ptp(fffffd8062dbaa00,1f5f23ed0000) at pmap_get_ptp+0xe8 sys/arch/amd64/amd64/pmap.c:1107 pmap_enter(fffffd8062dbaa00,1f5f23ed0000,6ef59000,1,20) at pmap_enter+0x2a8 uvm_fault(fffffd807f00a450,1f5f23ed1000,0,1) at uvm_fault+0xad6 sys/uvm/uvm_fault.c:803 pageflttrap() at pageflttrap+0x20b sys/arch/amd64/amd64/trap.c:199 usertrap(ffff800020abf9f0) at usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 recall_trap(6,1f,18,4,1f5fa9008400,1f5f8b3708e0) at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffecbf8, count: 5 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 140 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 __assert(ffffffff82207803,ffffffff821a7b14,8c,ffffffff82196f2c) at __assert+0x2b sys/kern/subr_prf.c:154 uvm_pagealloc(fffffd8062dbaa30,faf91f000,0,3) at uvm_pagealloc+0x476 sys/uvm/uvm_page.c:140 pmap_get_ptp(fffffd8062dbaa00,1f5f23ed0000) at pmap_get_ptp+0xe8 sys/arch/amd64/amd64/pmap.c:1107 pmap_enter(fffffd8062dbaa00,1f5f23ed0000,6ef59000,1,20) at pmap_enter+0x2a8 uvm_fault(fffffd807f00a450,1f5f23ed1000,0,1) at uvm_fault+0xad6 sys/uvm/uvm_fault.c:803 pageflttrap() at pageflttrap+0x20b sys/arch/amd64/amd64/trap.c:199 usertrap(ffff800020abf9f0) at usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 recall_trap(6,1f,18,4,1f5fa9008400,1f5f8b3708e0) at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffecbf8, count: -10 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020abf3e0 rbx 0xffff800020abf490 rdx 0xffff800020ab0508 rcx 0 rax 0 r8 0xffffffff81918aaf kprintf+0x16f r9 0x1 r10 0x25 r11 0x20c66746f08ba255 r12 0x3000000008 r13 0xffff800020abf3f0 r14 0x100 r15 0x1 rip 0xffffffff814a9118 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020abf3d0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (getty) pid=220704 stat=onproc flags process=100003 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020ab1160,0xffff800020ab0790 process=0xffff800020add880 user=0xffff800020aba000, vmspace=0xfffffd807f00a450 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 37704 144826 26972 0 2 0 syz-executor.0 37704 308736 26972 0 7 0x4000080 syz-executor.0 99258 356974 0 0 3 0x14200 acct acct 46043 46609 36279 0 3 0x82 nanosleep syz-executor.1 26972 171658 36279 0 3 0x82 nanosleep syz-executor.0 12541 325642 0 0 3 0x14200 bored sosplice * 7044 220704 1 0 7 0x100003 getty 36279 209165 54064 0 3 0x82 thrsleep syz-fuzzer 36279 101951 54064 0 3 0x4000082 nanosleep syz-fuzzer 36279 55364 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 104151 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 268628 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 286752 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 888 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 340902 54064 0 3 0x4000082 kqread syz-fuzzer 36279 132059 54064 0 3 0x4000082 thrsleep syz-fuzzer 36279 320352 54064 0 3 0x4000082 thrsleep syz-fuzzer 54064 337967 81233 0 3 0x10008a pause ksh 81233 390294 33527 0 3 0x92 select sshd 33527 439935 1 0 3 0x80 select sshd 31691 52825 50294 74 3 0x100092 bpf pflogd 50294 13586 1 0 3 0x80 netio pflogd 11285 135706 31197 73 3 0x100090 kqread syslogd 31197 435083 1 0 3 0x100082 netio syslogd 87925 45345 1 77 3 0x100090 poll dhclient 83673 119158 1 0 3 0x80 poll dhclient 56401 496098 0 0 3 0x14200 pgzero zerothread 30522 172019 0 0 3 0x14200 aiodoned aiodoned 26753 258292 0 0 3 0x14200 syncer update 86799 499658 0 0 3 0x14200 cleaner cleaner 15669 513591 0 0 3 0x14200 reaper reaper 2333 291030 0 0 3 0x14200 pgdaemon pagedaemon 96954 313035 0 0 3 0x14200 bored crynlk 37972 289184 0 0 3 0x14200 bored crypto 93018 13658 0 0 3 0x40014200 acpi0 acpi0 11063 244834 0 0 3 0x40014200 idle1 34223 332430 0 0 3 0x14200 bored softnet 11762 199473 0 0 3 0x14200 bored systqmp 30609 410026 0 0 3 0x14200 bored systq 39778 213650 0 0 3 0x40014200 bored softclock 46469 146401 0 0 3 0x40014200 idle0 16168 38428 0 0 3 0x14200 bored smr 1 405420 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &pmap->pm_mtx r = 0 (0xfffffd8062dbaa10) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pmap_enter+0x1bc rcr3 machine/cpufunc.h:141 [inline] #3 pmap_enter+0x1bc pmap_map_ptes sys/arch/amd64/amd64/pmap.c:418 [inline] #3 pmap_enter+0x1bc sys/arch/amd64/amd64/pmap.c:2610 #4 uvm_fault+0xad6 sys/uvm/uvm_fault.c:803 #5 pageflttrap+0x20b sys/arch/amd64/amd64/trap.c:199 #6 usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 #7 recall_trap+0x8 Process 7044 (getty) thread 0xffff800020ab0508 (220704) shared rwlock vmmaplk r = 0 (0xfffffd807f00a468) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1448 #2 uvm_fault+0x7f sys/uvm/uvm_fault.c:524 #3 pageflttrap+0x20b sys/arch/amd64/amd64/trap.c:199 #4 usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 #5 recall_trap+0x8 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82625ee0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 pageflttrap+0x6f sys/arch/amd64/amd64/trap.c:162 #2 usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 #3 recall_trap+0x8 exclusive mutex &pmap->pm_mtx r = 0 (0xfffffd8062dbaa10) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pmap_enter+0x1bc rcr3 machine/cpufunc.h:141 [inline] #3 pmap_enter+0x1bc pmap_map_ptes sys/arch/amd64/amd64/pmap.c:418 [inline] #3 pmap_enter+0x1bc sys/arch/amd64/amd64/pmap.c:2610 #4 uvm_fault+0xad6 sys/uvm/uvm_fault.c:803 #5 pageflttrap+0x20b sys/arch/amd64/amd64/trap.c:199 #6 usertrap+0x21a sys/arch/amd64/amd64/trap.c:369 #7 recall_trap+0x8 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9575 6440K 7076K 78643K 12982 0 0 pcb 13 10K 12K 78643K 248 0 0 rtable 74 11K 12K 78643K 960 0 0 ifaddr 73 15K 18K 78643K 290 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1548 0 0 iov 0 0K 32K 78643K 243 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 77K 78643K 2211 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 14 0 0 VM map 14 7K 7K 78643K 21 0 0 sem 12 1K 1K 78643K 266 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 1165 0 0 sigio 0 0K 0K 78643K 19 0 0 proc 60 63K 95K 78643K 828 0 0 subproc 32 2K 2K 78643K 136 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 1K 78643K 151 0 0 in_multi 14 0K 2K 78643K 165 0 0 ether_multi 1 0K 0K 78643K 14 0 0 mrt 0 0K 0K 78643K 11 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 78 344K 344K 78643K 78 0 0 exec 0 0K 1K 78643K 435 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 127 112K 112K 78643K 5040 0 0 UVM aobj 62 5K 5K 78643K 66 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 267 0 0 NDP 18 0K 0K 78643K 88 0 0 temp 213 3564K 3637K 78643K 32617 0 0 kqueue 0 0K 0K 78643K 12 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 35 0 32 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 90 0 88 1 0 1 1 0 8 0 rtentry 112 170 0 145 2 0 2 2 0 8 0 unpcb 120 715 0 705 1 0 1 1 0 8 0 syncache 264 7 0 7 3 3 0 1 0 8 0 tcpqe 32 14 0 14 2 2 0 1 0 8 0 tcpcb 544 899 0 895 13 12 1 12 0 8 0 inpcb 280 2062 0 2055 12 11 1 9 0 8 0 rttmr 72 4 0 4 3 3 0 1 0 8 0 nd6 48 26 0 26 1 0 1 1 0 8 1 pkpcb 40 4 0 4 1 1 0 1 0 8 0 ppxss 1128 32 0 32 3 2 1 1 0 8 1 pffrag 232 34 0 34 3 2 1 1 0 482 1 pffrnode 88 34 0 34 3 2 1 1 0 8 1 pffrent 40 866 0 866 3 2 1 1 0 8 1 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 115 0 59 1 0 1 1 0 8 0 pfstkey 112 115 0 59 3 0 3 3 0 8 0 pfstate 328 115 0 59 6 0 6 6 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 3 0 2 3 2 1 3 0 8 0 art_heap4 256 713 0 584 19 5 14 16 0 8 3 art_table 32 716 0 586 2 0 2 2 0 8 0 art_node 16 169 0 146 1 0 1 1 0 8 0 sysvmsgpl 40 31 0 17 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 258 0 248 1 0 1 1 0 8 0 shmpl 112 64 0 4 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 3244 0 1833 46 0 46 46 0 8 0 ffsino 272 3244 0 1833 96 1 95 95 0 8 0 nchpl 144 5157 0 3550 61 0 61 61 0 8 0 uvmvnodes 72 3927 0 0 72 0 72 72 0 8 0 vnodes 208 3927 0 0 207 0 207 207 0 8 0 namei 1024 18873 0 18873 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 13 0 1 2 0 2 2 0 8 0 vmpool 552 19 0 7 1 0 1 1 0 8 0 scxspl 192 16149 0 16149 16 12 4 7 0 8 4 plimitpl 152 106 0 98 1 0 1 1 0 8 0 sigapl 432 1348 0 1333 3 1 2 3 0 8 0 futexpl 56 26245 0 26245 1 0 1 1 0 8 1 knotepl 112 329 0 310 1 0 1 1 0 8 0 kqueuepl 104 364 0 362 4 3 1 4 0 8 0 pipepl 112 1748 0 1729 6 4 2 2 0 8 1 fdescpl 488 1349 0 1333 3 0 3 3 0 8 0 filepl 152 13424 0 13324 18 12 6 13 0 8 2 lockfpl 104 450 0 449 1 0 1 1 0 8 0 lockfspl 48 142 0 141 1 0 1 1 0 8 0 sessionpl 112 25 0 14 1 0 1 1 0 8 0 pgrppl 48 47 0 36 1 0 1 1 0 8 0 ucredpl 96 2935 0 2926 1 0 1 1 0 8 0 zombiepl 144 1333 0 1332 1 0 1 1 0 8 0 processpl 896 1366 0 1332 4 0 4 4 0 8 0 procpl 632 3934 0 3890 6 1 5 5 0 8 1 srpgc 64 12 0 12 3 3 0 1 0 8 0 sosppl 128 25 0 25 4 3 1 1 0 8 1 sockpl 384 2883 0 2864 19 16 3 14 0 8 1 mcl64k 65536 511 0 0 64 8 56 64 0 8 0 mcl16k 16384 6 0 0 1 0 1 1 0 8 0 mcl12k 12288 21 0 0 2 0 2 2 0 8 0 mcl9k 9216 4 0 0 1 0 1 1 0 8 0 mcl8k 8192 12 0 0 2 0 2 2 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 154 0 0 19 0 19 19 0 8 0 mtagpl 80 32 0 0 1 0 1 1 0 8 0 mbufpl 256 590 0 0 37 0 37 37 0 8 0 bufpl 256 9735 0 2687 441 0 441 441 0 8 0 anonpl 16 174348 0 155507 120 34 86 92 0 124 8 amapchunkpl 152 9330 0 9204 24 17 7 12 0 158 0 amappl16 192 7208 0 6149 83 26 57 65 0 8 3 amappl15 184 449 0 449 1 1 0 1 0 8 0 amappl14 176 65 0 62 1 0 1 1 0 8 0 amappl13 168 255 0 254 2 1 1 1 0 8 0 amappl12 160 16 0 14 2 1 1 1 0 8 0 amappl11 152 496 0 479 1 0 1 1 0 8 0 amappl10 144 53 0 49 1 0 1 1 0 8 0 amappl9 136 826 0 819 1 0 1 1 0 8 0 amappl8 128 368 0 335 3 1 2 2 0 8 0 amappl7 120 102 0 95 1 0 1 1 0 8 0 amappl6 112 488 0 474 1 0 1 1 0 8 0 amappl5 104 186 0 171 1 0 1 1 0 8 0 amappl4 96 1795 0 1763 1 0 1 1 0 8 0 amappl3 88 167 0 157 1 0 1 1 0 8 0 amappl2 80 9837 0 9763 3 1 2 3 0 8 0 amappl1 72 39654 0 39210 25 15 10 20 0 8 0 amappl 80 4295 0 4250 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 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 17 0 17 1 1 0 1 0 8 0 aobjpl 64 65 0 4 1 0 1 1 0 8 0 uaddrrnd 24 1368 0 1333 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1368 0 1333 1 0 1 1 0 8 0 vmmpekpl 168 16673 0 16636 2 0 2 2 0 8 0 vmmpepl 168 177757 0 175526 175 51 124 138 0 357 22 vmsppl 368 1348 0 1333 2 0 2 2 0 8 0 pdppl 4096 2743 0 2692 7 0 7 7 0 8 0 pvpl 32 483536 0 461493 258 51 207 212 0 265 25 pmappl 232 1367 0 1340 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 713 0 31 20 0 20 20 0 8 0