syzbot


uvm_fault: refcnt_take

Status: fixed on 2024/01/19 12:22
Reported-by: syzbot+54fba1c004d7383d5e85@syzkaller.appspotmail.com
Fix commit: 470ec98d6191 Backout priterator() for walking allprocess list.
First crash: 311d, last: 311d

Sample crash report:
uvm_fault(0xfffffd8008b56740, 0xcf, 0, 2) -> e
kernel: page fault trap, code=2
Stopped at      refcnt_take+0x2d:       lock xaddl      %eax,0(%r14)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*464392  86228  32767        0x10  0x4000000    1K syz-executor.6
 463275  34931      0     0x14000      0x200    0  softnet0
refcnt_take(cf) at refcnt_take+0x2d _atomic_add_int_nv machine/atomic.h:210 [inline]
refcnt_take(cf) at refcnt_take+0x2d sys/kern/kern_synch.c:795
priterator(ffff8000ffff0018) at priterator+0x65 sys/kern/kern_proc.c:241
sysctl_file(ffff800030b10ba8,4,20000100,ffff800030b10bd8,ffff80002a262548) at sysctl_file+0x75c
kern_sysctl(ffff800030b10ba4,5,20000100,ffff800030b10bd8,0,fffffffffffffe59,35c94796f2531b81) at kern_sysctl+0x10b sys/kern/kern_sysctl.c:457
sys_sysctl(ffff80002a262548,ffff800030b10c40,ffff800030b10c90) at sys_sysctl+0x219 sys/kern/kern_sysctl.c:254
syscall(ffff800030b10d40) at syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
syscall(ffff800030b10d40) at syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd4d1821e070, count: 8
https://www.openbsd.org/ddb.html describes the minimum info required in bug
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ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
*cpu1: uvm_fault(0xfffffd8008b56740, 0xcf, 0, 2) -> e
ddb{1}> trace
refcnt_take(cf) at refcnt_take+0x2d _atomic_add_int_nv machine/atomic.h:210 [inline]
refcnt_take(cf) at refcnt_take+0x2d sys/kern/kern_synch.c:795
priterator(ffff8000ffff0018) at priterator+0x65 sys/kern/kern_proc.c:241
sysctl_file(ffff800030b10ba8,4,20000100,ffff800030b10bd8,ffff80002a262548) at sysctl_file+0x75c
kern_sysctl(ffff800030b10ba4,5,20000100,ffff800030b10bd8,0,fffffffffffffe59,35c94796f2531b81) at kern_sysctl+0x10b sys/kern/kern_sysctl.c:457
sys_sysctl(ffff80002a262548,ffff800030b10c40,ffff800030b10c90) at sys_sysctl+0x219 sys/kern/kern_sysctl.c:254
syscall(ffff800030b10d40) at syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
syscall(ffff800030b10d40) at syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd4d1821e070, count: -7
ddb{1}> show registers
rdi                             0xcf
rsi                              0x1
rbp               0xffff800030b108c0
rbx                              0x4
rdx                                0
rcx               0xffff80002a262548
rax                              0x1
r8                    0x7f7fffffc000
r9                0xffff8000ffff0018
r10               0xf6cde93e44c4a0c3
r11               0xafc6d7dc645897fd
r12               0xfffffd80760bc5d0
r13                           0x7fbf    __ALIGN_SIZE+0x6fbf
r14                             0xcf
r15               0xffffffffffffffff
rip               0xffffffff81f4cf1d    refcnt_take+0x2d
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff800030b10880
ss                              0x10
refcnt_take+0x2d:       lock xaddl      %eax,0(%r14)
ddb{1}> show proc
PROC (syz-executor.6) tid=464392 pid=86228 tcnt=3 stat=onproc
    flags process=10<SUGID> proc=4000000<THREAD>
    runpri=32, usrpri=80, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0
    forw=0xffffffffffffffff, list=0xffff80002a262a98,0xffff80002a2622b0
    process=0xffff8000ffff0908 user=0xffff800030b0b000, vmspace=0xfffffd8008b56740
    estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 34085    6065  56907  32767  2        0x10                syz-executor.1
 86228  330340  84339  32767  2        0x10                syz-executor.6
*86228  464392  84339  32767  7   0x4000010                syz-executor.6
 86228  485665  84339  32767  3   0x4000090  fsleep        syz-executor.6
 79075  325812   6605  32767  2        0x10                syz-executor.4
  3729  279069  85290  32767  3        0x90  nanoslp       syz-executor.3
  3729   27348  85290  32767  3   0x4000090  piperd        syz-executor.3
  3729  319116  85290  32767  3   0x4000090  piperd        syz-executor.3
  3729  500832  85290  32767  3   0x4000090  fsleep        syz-executor.3
 84339  441617  32359  32767  3        0x90  nanoslp       syz-executor.6
 32359   68138  93041      0  3        0x82  wait          syz-executor.6
 27121   36755  84018  32767  3        0x90  nanoslp       syz-executor.2
 84018  421918  93041      0  3        0x82  wait          syz-executor.2
 85290  314208  36749  32767  3        0x90  nanoslp       syz-executor.3
 36749  187553  93041      0  3        0x82  wait          syz-executor.3
 56907  223144  47590  32767  3        0x90  nanoslp       syz-executor.1
 47590  482907  93041      0  3        0x82  wait          syz-executor.1
 25860  246745  74225  32767  2        0x10                syz-executor.5
 74225   39236  93041      0  3        0x82  wait          syz-executor.5
 40869  504370  93981  32767  3        0x90  nanoslp       syz-executor.7
 93981   91861  93041      0  3        0x82  wait          syz-executor.7
  6605  325577  78110  32767  2        0x10                syz-executor.4
 78110  340818  93041      0  3        0x82  wait          syz-executor.4
 99408  260038  17818  32767  2        0x10                syz-executor.0
 17818   32423  93041      0  3        0x82  wait          syz-executor.0
 43353  147436      0      0  3     0x14200  bored         sosplice
 93041  501535  50943      0  3   0x2000082  wait          syz-fuzzer
 93041   60279  50943      0  2   0x6000082                syz-fuzzer
 93041  140915  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  251680  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041  255730  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  126393  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  157775  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041  224233  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  309889  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041   37600  50943      0  3   0x6000082  kqread        syz-fuzzer
 93041   11442  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041  299445  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041   25135  50943      0  3   0x6000082  thrsleep      syz-fuzzer
 93041  194614  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  233501  50943      0  3   0x6000082  wait          syz-fuzzer
 93041  218049  50943      0  3   0x6000082  wait          syz-fuzzer
 50943  154028  70194      0  3    0x10008a  sigsusp       ksh
 70194  128850  67398      0  3        0x9a  kqread        sshd
 21920  144726      1      0  3    0x100083  ttyin         getty
 67398  250625      1      0  3        0x88  kqread        sshd
 17492  167816  51478     73  3   0x1100090  kqread        syslogd
 51478   89612      1      0  3    0x100082  netio         syslogd
 18424  240933      1      0  3    0x100080  kqread        resolvd
 29720  195999   8794     77  3    0x100092  kqread        dhcpleased
 48519   48577   8794     77  3    0x100092  kqread        dhcpleased
  8794  381562      1      0  3        0x80  kqread        dhcpleased
 96009  369148      0      0  3     0x14200  bored         smr
 56590  272655      0      0  2     0x14200                zerothread
 45346  177835      0      0  3     0x14200  aiodoned      aiodoned
 84457  434167      0      0  3     0x14200  syncer        update
 59266  140894      0      0  3     0x14200  cleaner       cleaner
 67017   93108      0      0  3     0x14200  reaper        reaper
 77262  299286      0      0  3     0x14200  pgdaemon      pagedaemon
 87269  312868      0      0  3     0x14200  bored         viomb
  1386  517047      0      0  3  0x40014200  acpi0         acpi0
 25335  276276      0      0  3  0x40014200                idle1
 72437   11812      0      0  3     0x14200  bored         softnet3
 93292   55746      0      0  3     0x14200  bored         softnet2
 35048  458052      0      0  3     0x14200  bored         softnet1
 34931  463275      0      0  7     0x14200                softnet0
 13171  489926      0      0  3     0x14200  bored         systqmp
 88752  477395      0      0  3     0x14200  bored         systq
 19283  361687      0      0  3     0x14200  tmoslp        softclockmp
 76617   99874      0      0  3  0x40014200  tmoslp        softclock
 63830   76038      0      0  3  0x40014200                idle0
     1  131670      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 86228 (syz-executor.6) thread 0xffff80002a262548 (464392)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82e71648)
#0  witness_lock+0x447
#1  __mp_acquire_count+0x48 sys/kern/kern_lock.c:227
#2  mi_switch+0x46d sys/kern/sched_bsd.c:470
#3  sleep_finish+0x19b sys/kern/kern_synch.c:414
#4  rw_enter+0x341 sys/kern/kern_rwlock.c:285
#5  fill_file+0x30a sys/kern/kern_sysctl.c:1290
#6  sysctl_file+0x62d sys/kern/kern_sysctl.c:1585
#7  kern_sysctl+0x10b sys/kern/kern_sysctl.c:457
#8  sys_sysctl+0x219 sys/kern/kern_sysctl.c:254
#9  syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
#9  syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
#10 Xsyscall+0x128
exclusive rwlock sysctllk r = 0 (0xffffffff82cfc800)
#0  witness_lock+0x447
#1  rw_enter+0x3c8 sys/kern/kern_rwlock.c:309
#2  sys_sysctl+0x1c3 sys/kern/kern_sysctl.c:238
#3  syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
#3  syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
#4  Xsyscall+0x128
Process 34931 (softnet0) thread 0xffff80002a10b000 (463275)
shared rwlock softnet0 r = 0 (0xffff80000002d070)
#0  witness_lock+0x447
#1  taskq_thread+0xca sys/kern/kern_task.c:446
#2  proc_trampoline+0x10
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf 10224   6414K    6421K 166960K     11415        0
            pcb    15     24K      28K 166960K        25        0
         rtable   246      7K       7K 166960K      3777        0
             pf    29      8K       8K 166960K       103        0
         ifaddr    44     15K      16K 166960K       198        0
        ifgroup    50      2K       2K 166960K       198        0
         sysctl     4      1K       5K 166960K        12        0
       counters    64     36K      36K 166960K       138        0
       ioctlops     0      0K       2K 166960K       533        0
            iov     0      0K      44K 166960K      4848        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1279     80K      80K 166960K      7441        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       9K 166960K       414        0
         VM map     2      1K       1K 166960K         2        0
            sem    12      0K       0K 166960K      7444        0
        dirhash    12      2K       2K 166960K        12        0
           ACPI  1697    195K     286K 166960K     12548        0
      file desc    23     85K     121K 166960K     34462        0
          sigio     0      0K       0K 166960K      1381        0
           proc    56     78K     127K 166960K      3441        0
        subproc   104      6K       6K 166960K       585        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
    ip_moptions     0      0K       0K 166960K      3724        0
       in_multi    99      7K       7K 166960K       876        0
    ether_multi     1      0K       0K 166960K        33        0
            mrt     1      0K       0K 166960K         3        0
    ISOFS mount     1     32K      32K 166960K         1        0
  MSDOSFS mount     1     16K      16K 166960K         1        0
           ttys   265   1182K    1182K 166960K       265        0
           exec     0      0K       1K 166960K      4451        0
            tdb     3      0K       0K 166960K         3        0
        pagedep     1      8K       8K 166960K         1        0
       inodedep     1     32K      32K 166960K         1        0
         newblk     1      0K       0K 166960K         1        0
        VM swap     8     62K      64K 166960K        10        0
       UVM amap   448     90K     110K 166960K    342186        0
       UVM aobj   131      4K       4K 166960K       134        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     1      0K       0K 166960K       855        0
            NDP    11      0K       2K 166960K       138        0
           temp    75   6713K    6840K 166960K     85690        0
         kqueue    12     18K      31K 166960K      3206        0
      SYN cache     2     16K      16K 166960K         2        0
ddb{1}> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
plcache    128       24    0        0     1     0     1     1     0     8    0
rtpcb      120     2562    0     2559    30    29     1     5     0     8    0
rtentry    112      561    0      445     4     0     4     4     0     8    0
unpcb      144    24933    0    24916   207   201     6    11     0     8    5
syncache   312      455    0      455    60    60     0     1     0     8    0
tcpqe       32      498    0      498    55    55     0     1     0     8    0
tcpcb      808    17537    0    17503   311   306     5    21     0     8    0
arp        120       97    0       78     1     0     1     1     0     8    0
ipq         40       59    0       56    19    18     1     1     0     8    0
ipqe        40      679    0      673    19    18     1     1     0     8    0
inpcb      368    37695    0    37656   412   402    10    21     0     8    3
nd6        136      173    0      144     5     3     2     2     0     8    0
kcovpl      48       45    0       37     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256     2196    0     1724    36     6    30    30     0     8    0
art_table   32     2197    0     1724     4     0     4     4     0     8    0
art_node    16      560    0      454     1     0     1     1     0     8    0
semupl     112        5    0        5     2     2     0     1     0     8    0
semapl     112     7442    0     7432     1     0     1     1     0     8    0
shmpl      112      131    0        3     4     0     4     4     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256    46082    0    44585    94     0    94    94     0     8    0
ffsino     272    46082    0    44585   100     0   100   100     0     8    0
nchpl      144    91687    0    90041    63     0    63    63     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  290324    0   290324     9     8     1     2     0     8    1
percpumem   16       83    0       37     1     0     1     1     0     8    0
kstatmem   264       96    0       74     2     0     2     2     0     8    0
scxspl     216   291115    0   291115   127   124     3     8     1     8    3
plimitpl   152     4596    0     4573    47    46     1     2     0     8    0
sigapl     424    34679    0    34625     7     0     7     7     0     8    0
futexpl     64   285556    0   285554     9     8     1     1     0     8    0
knotepl    120     1135    0        0     8     0     8     8     0     8    0
kqueuepl   216     7797    0     7789   127   126     1     7     0     8    0
pipepl     320     7299    0     7270   163   154     9    14     0     8    6
fdescpl    496    34660    0    34626     6     1     5     6     0     8    0
filepl     152   214692    0   214445   321   305    16    24     0     8    4
lockfpl    104     5364    0     5362     3     2     1     2     0     8    0
lockfspl    48     1437    0     1435     1     0     1     1     0     8    0
sessionpl  144       60    0       44     1     0     1     1     0     8    0
pgrppl      48      886    0      870     1     0     1     1     0     8    0
ucredpl    104    34740    0    34722     1     0     1     1     0     8    0
zombiepl   144    34627    0    34625     1     0     1     1     0     8    0
processpl  1144   34679    0    34625     5     0     5     5     0     8    0
procpl     680    97219    0    97145    15     7     8     9     0     8    0
sosppl     168      696    0      694    31    30     1     1     0     8    0
sockpl     488    68519    0    68461   948   924    24    40     0     8   15
mcl64k     65536     49    0        0     4     1     3     3     0     8    0
mcl16k     16384     33    0        0     3     0     3     3     0     8    0
mcl12k     12288     46    0        0     2     0     2     2     0     8    0
mcl9k      9216      28    0        0     2     1     1     2     0     8    0
mcl8k      8192      61    0        0     5     3     2     3     0     8    0
mcl4k      4096     105    0        0     4     1     3     4     0     8    0
mcl2k2     2112      22    0        0     2     0     2     2     0     8    0
mcl2k      2048     627    0        0    38    19    19    31     0     8    0
mtagpl      96       10    0        0     1     0     1     1     0     8    0
mbufpl     256     4677    0        0   219     0   219   219     0     8    0
bufpl      288    72822    0    66506   452     0   452   452     0     8    0
anonpl      24  3548037    0  3535303   266   160   106   117     0   186    0
amapchunkpl 152 1118858    0  1117961   245   203    42    55     0   158    0
amappl16   200    83169    0    82849   361   338    23    37     0     8    1
amappl15   192       49    0       48     6     5     1     1     0     8    0
amappl14   184      280    0      267     2     1     1     2     0     8    0
amappl13   176       15    0       15     6     6     0     1     0     8    0
amappl12   168    35917    0    35869     4     1     3     3     0     8    0
amappl11   160       49    0       39     1     0     1     1     0     8    0
amappl10   152       74    0       61     1     0     1     1     0     8    0
amappl9    144      481    0      481    62    61     1     1     0     8    1
amappl8    136     1644    0     1420     8     0     8     8     0     8    0
amappl7    128      412    0      385     2     0     2     2     0     8    0
amappl6    120     1149    0     1126     1     0     1     1     0     8    0
amappl5    112      871    0      862     1     0     1     1     0     8    0
amappl4    104     1470    0     1427     3     1     2     2     0     8    0
amappl3     96   211136    0   211041    27    23     4     4     0     8    0
amappl2     88    37310    0    37213     5     2     3     3     0     8    0
amappl1     80   130419    0   129901    22    10    12    22     0     8    0
amappl      88   339792    0   339530     8     0     8     8     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      133    0        3     3     0     3     3     0     8    0
uaddrrnd    24    34660    0    34626     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24    34660    0    34626     1     0     1     1     0     8    0
vmmpekpl   168   264754    0   264690     4     0     4     4     0     8    0
vmmpepl    168  2016481    0  2013922   547   415   132   150     0   357    0
vmsppl     464    34659    0    34626     6     1     5     6     0     8    0
rwobjpl     56   503285    0   495685   117     5   112   112     0     8    0
pdppl      4096   69327    0    69252   901   820    81    93     0     8    6
pvpl        32    44111    0        0   356     0   356   356     0   265    0
pmappl     248    34659    0    34626     3     0     3     3     0     8    0
extentpl    40       56    0       38     1     0     1     1     0     8    0
phpool     112     2670    0     1635    31     0    31    31     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x1e:        addq    $0x8,%rsp
x86_ipi_db(ffffffff82cc7ff0) at x86_ipi_db+0x1e sys/arch/amd64/amd64/db_interface.c:393
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff82e71440) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82e71440) at __mp_lock+0x122 sys/kern/kern_lock.c:147
softintr_dispatch(0) at softintr_dispatch+0x52 sys/arch/amd64/amd64/softintr.c:88
Xsoftclock() at Xsoftclock+0x27
__mp_lock(ffffffff82e71440) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82e71440) at __mp_lock+0x129 sys/kern/kern_lock.c:147
if_qstart_compat(ffff8000001a1550) at if_qstart_compat+0x1e sys/net/if.c:716
ifq_serialize(ffff8000001a1550,ffff8000001a1678) at ifq_serialize+0x16e sys/net/ifq.c:113
taskq_thread(ffff80000002d000) at taskq_thread+0xe5 sys/kern/kern_task.c:450
end trace frame: 0x0, count: 5
ddb{0}> trace
x86_ipi_db(ffffffff82cc7ff0) at x86_ipi_db+0x1e sys/arch/amd64/amd64/db_interface.c:393
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff82e71440) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82e71440) at __mp_lock+0x122 sys/kern/kern_lock.c:147
softintr_dispatch(0) at softintr_dispatch+0x52 sys/arch/amd64/amd64/softintr.c:88
Xsoftclock() at Xsoftclock+0x27
__mp_lock(ffffffff82e71440) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82e71440) at __mp_lock+0x129 sys/kern/kern_lock.c:147
if_qstart_compat(ffff8000001a1550) at if_qstart_compat+0x1e sys/net/if.c:716
ifq_serialize(ffff8000001a1550,ffff8000001a1678) at ifq_serialize+0x16e sys/net/ifq.c:113
taskq_thread(ffff80000002d000) at taskq_thread+0xe5 sys/kern/kern_task.c:450
end trace frame: 0x0, count: -10
ddb{0}> machine ddbcpu 1
Stopped at      refcnt_take+0x2d:       lock xaddl      %eax,0(%r14)
refcnt_take(cf) at refcnt_take+0x2d _atomic_add_int_nv machine/atomic.h:210 [inline]
refcnt_take(cf) at refcnt_take+0x2d sys/kern/kern_synch.c:795
priterator(ffff8000ffff0018) at priterator+0x65 sys/kern/kern_proc.c:241
sysctl_file(ffff800030b10ba8,4,20000100,ffff800030b10bd8,ffff80002a262548) at sysctl_file+0x75c
kern_sysctl(ffff800030b10ba4,5,20000100,ffff800030b10bd8,0,fffffffffffffe59,35c94796f2531b81) at kern_sysctl+0x10b sys/kern/kern_sysctl.c:457
sys_sysctl(ffff80002a262548,ffff800030b10c40,ffff800030b10c90) at sys_sysctl+0x219 sys/kern/kern_sysctl.c:254
syscall(ffff800030b10d40) at syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
syscall(ffff800030b10d40) at syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd4d1821e070, count: 8
ddb{1}> trace
refcnt_take(cf) at refcnt_take+0x2d _atomic_add_int_nv machine/atomic.h:210 [inline]
refcnt_take(cf) at refcnt_take+0x2d sys/kern/kern_synch.c:795
priterator(ffff8000ffff0018) at priterator+0x65 sys/kern/kern_proc.c:241
sysctl_file(ffff800030b10ba8,4,20000100,ffff800030b10bd8,ffff80002a262548) at sysctl_file+0x75c
kern_sysctl(ffff800030b10ba4,5,20000100,ffff800030b10bd8,0,fffffffffffffe59,35c94796f2531b81) at kern_sysctl+0x10b sys/kern/kern_sysctl.c:457
sys_sysctl(ffff80002a262548,ffff800030b10c40,ffff800030b10c90) at sys_sysctl+0x219 sys/kern/kern_sysctl.c:254
syscall(ffff800030b10d40) at syscall+0x5f0 mi_syscall sys/sys/syscall_mi.h:182 [inline]
syscall(ffff800030b10d40) at syscall+0x5f0 sys/arch/amd64/amd64/trap.c:591
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd4d1821e070, count: -7

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/18 12:10 openbsd d1ecb0c52710 239abf84 .config console log report ci-openbsd-setuid uvm_fault: refcnt_take
* Struck through repros no longer work on HEAD.