syzbot


uvm_fault: uao_detach

Status: upstream: reported on 2024/09/26 12:18
Reported-by: syzbot+7099c98dfcc4931fec37@syzkaller.appspotmail.com
First crash: 2d11h, last: 2d11h

Sample crash report:
uvm_fault(0xfffffd807a287970, 0x3f, 0, 2) -> e
kernel: page fault trap, code=2
Stopped at      uao_detach+0xb9:        movq    %rax,0x40(%r15)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*160794  35252      0           0  0x4000000    0  syz-executor
uao_detach(fffffd807e14bc60) at uao_detach+0xb9 sys/uvm/uvm_aobj.c:824
shm_deallocate_segment(fffffd8075cefa80) at shm_deallocate_segment+0x43 sys/kern/sysv_shm.c:152
sys_shmat(ffff80002a48d458,ffff800037679c40,ffff800037679b90) at sys_shmat+0x573 sys/kern/sysv_shm.c:278
syscall(ffff800037679c40) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x4b6d7dc4380, count: 10
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: uvm_fault(0xfffffd807a287970, 0x3f, 0, 2) -> e
ddb> trace
uao_detach(fffffd807e14bc60) at uao_detach+0xb9 sys/uvm/uvm_aobj.c:824
shm_deallocate_segment(fffffd8075cefa80) at shm_deallocate_segment+0x43 sys/kern/sysv_shm.c:152
sys_shmat(ffff80002a48d458,ffff800037679c40,ffff800037679b90) at sys_shmat+0x573 sys/kern/sysv_shm.c:278
syscall(ffff800037679c40) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x4b6d7dc4380, count: -5
ddb> show registers
rdi               0xffff800030e04000
rsi                            0x12c
rbp               0xffff800037679a80
rbx               0xfffffd8075cefae8
rdx               0xffff800030e04000
rcx                            0x12b
rax               0xffffffffffffffff
r8                        0x20003000
r9                            0x3000    __ALIGN_SIZE+0x2000
r10               0x2197eebded698252
r11               0xb59bf6591c883df4
r12                            0x200
r13               0xfffffd8075cefa80
r14               0xfffffd807e14bc60
r15               0xffffffffffffffff
rip               0xffffffff8226b179    uao_detach+0xb9
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff800037679a40
ss                              0x10
uao_detach+0xb9:        movq    %rax,0x40(%r15)
ddb> show proc
PROC (syz-executor) tid=160794 pid=35252 tcnt=3 stat=onproc
    flags process=0 proc=4000000<THREAD>
    runpri=32, usrpri=82, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff8000376676f0,0xffff80002a48c538
    process=0xffff8000ffffaf28 user=0xffff800037674000, vmspace=0xfffffd807a287970
    estcpu=32, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 52067   65255  83528      0  2           0                syz-executor
 52067  130911  83528      0  3   0x4000080  fsleep        syz-executor
  4947   31144  59380      0  2           0                syz-executor
  4947  280665  59380      0  2   0x4000000                syz-executor
  4947  170876  59380      0  2   0x4000000                syz-executor
 87971  294646  89340      0  2           0                syz-executor
 87971  248209  89340      0  3   0x4000080  fsleep        syz-executor
 87971  278106  89340      0  2   0x4000000                syz-executor
 41993  134601  31274     -1  2        0x10                syz-executor
 41993   71220  31274     -1  3   0x4000090  sbwait        syz-executor
 41993  146875  31274     -1  2   0x4000010                syz-executor
 35252  310838  85490      0  2           0                syz-executor
*35252  160794  85490      0  7   0x4000000                syz-executor
 35252  214243  85490      0  2   0x4000000                syz-executor
 10607  380526  25389      0  2           0                syz-executor
 10607  331314  25389      0  2   0x4000000                syz-executor
 10607  478385  25389      0  3   0x4000000  inode         syz-executor
 97674  404146   2618      0  3      0x3000  suspend       syz-executor
 97674  199735   2618      0  2   0x4081000                syz-executor
 59380  288687  51891      0  3        0x82  nanoslp       syz-executor
 72876   28385  51891      0  3         0x2  biowait       syz-executor
 25389  291969  51891      0  3        0x82  nanoslp       syz-executor
 85490  522823  51891      0  3        0x82  nanoslp       syz-executor
  2618  359984  51891      0  3        0x82  nanoslp       syz-executor
 83528   20252  51891      0  3        0x82  nanoslp       syz-executor
 31274  158789  51891      0  3        0x82  nanoslp       syz-executor
 89340   87337  51891      0  3        0x82  nanoslp       syz-executor
 97725  178750      0      0  3     0x14200  bored         sosplice
 51891  257700  12373      0  3        0x82  kqread        syz-executor
 12373  470267  20144      0  3    0x10008a  sigsusp       ksh
 20144  177871  44221      0  3        0x98  kqread        sshd-session
 44221   35186  68601      0  3        0x92  kqread        sshd-session
 88907  107581      1      0  3    0x100083  ttyin         getty
 68601   37000      1      0  3        0x88  kqread        sshd
  5974  187788  17706     73  3   0x1100090  kqread        syslogd
 17706  216152      1      0  3    0x100082  sbwait        syslogd
 40953  178354      1      0  3    0x100080  kqread        resolvd
 16858  304742  37534     77  3    0x100092  kqread        dhcpleased
 28265  272583  37534     77  3    0x100092  kqread        dhcpleased
 37534  369449      1      0  3        0x80  kqread        dhcpleased
 83898  433799      0      0  3     0x14200  bored         smr
 99498  169821      0      0  2     0x14200                zerothread
 50945  196916      0      0  3     0x14200  aiodoned      aiodoned
 77605   43234      0      0  3     0x14200  syncer        update
  6040  199878      0      0  3     0x14200  cleaner       cleaner
 58774  135170      0      0  3     0x14200  reaper        reaper
 10053  127885      0      0  3     0x14200  pgdaemon      pagedaemon
 21231  231847      0      0  3     0x14200  bored         viomb
 30509  329165      0      0  3  0x40014200  acpi0         acpi0
 27559  483467      0      0  3     0x14200  bored         softnet3
  5686  194290      0      0  3     0x14200  bored         softnet2
 77038  400753      0      0  3     0x14200  bored         softnet1
 85286   93827      0      0  3     0x14200  bored         softnet0
 66991  408035      0      0  3     0x14200  bored         systqmp
 56181  305360      0      0  3     0x14200  bored         systq
 75820  214079      0      0  3  0x40014200  tmoslp        softclock
 28608  261543      0      0  3  0x40014200                idle0
     1  345869      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 10180  14131K   14382K 166960K     11420        0
            pcb    17     14K      16K 166960K       119        0
         rtable   234      9K       9K 166960K       613        0
             pf    32     13K      13K 166960K        50        0
         ifaddr    42      7K       7K 166960K        81        0
        ifgroup    54      2K       2K 166960K        88        0
         sysctl     2      0K       0K 166960K         2        0
       counters    31     17K      17K 166960K        40        0
       ioctlops     0      0K       4K 166960K        47        0
            iov     1     16K      16K 166960K         7        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1367     86K      86K 166960K      1581        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     3      5K       5K 166960K         6        0
         VM map     2      1K       1K 166960K         2        0
            sem    12      0K       0K 166960K        13        0
        dirhash    12      2K       2K 166960K        12        0
           ACPI  1690    195K     286K 166960K     12418        0
      file desc    17     61K      81K 166960K       397        0
          sigio     0      0K       0K 166960K         3        0
           proc    60     59K      83K 166960K       714        0
        subproc   104      6K       6K 166960K       208        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
    ip_moptions     0      0K       0K 166960K        19        0
       in_multi    98      7K       7K 166960K       190        0
    ether_multi     1      0K       0K 166960K         2        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    61    281K     281K 166960K        61        0
           exec     0      0K       1K 166960K       461        0
            tdb     3      0K       0K 166960K         3        0
        VM swap     8     62K      64K 166960K        10        0
       UVM amap   230     72K      74K 166960K      4687        0
       UVM aobj     7      2K       2K 166960K         8        0
     pinsyscall    38     76K      89K 166960K      1618        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     0      0K       0K 166960K        13        0
            NDP    12      0K       2K 166960K        53        0
           temp    38   6803K    6899K 166960K     13132        0
         kqueue    14     22K      28K 166960K        47        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       63    0       58     1     0     1     1     0     8    0
rtentry    112      201    0       94     4     0     4     4     0     8    0
unpcb      144      143    0      120     2     0     2     2     0     8    1
syncache   336        3    0        3     1     1     0     1     0     8    0
tcpcb      808       51    0       46     1     0     1     1     0     8    0
arp         88       34    0       16     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      336      306    0      298     7     0     7     7     0     8    6
nd6        104       48    0       24     1     0     1     1     0     8    0
kcovpl      48       16    0        8     1     0     1     1     0     8    0
ppxss      1072       1    0        1     1     0     1     1     0     8    1
art_heap8  4096       2    0        1     2     0     2     2     0     8    1
art_heap4  256      813    0      364    31     2    29    29     0     8    0
art_table   32      815    0      365     4     0     4     4     0     8    0
art_node    16      200    0      103     1     0     1     1     0     8    0
sysvmsgpl   40       34    0       33     1     0     1     1     0     8    0
semapl     112       11    0        1     1     0     1     1     0     8    0
shmpl      112        5    0        1     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1805    0      292    95     0    95    95     0     8    0
ffsino     240     1805    0      292    90     0    90    90     0     8    0
nchpl      144     2180    0      495    63     0    63    63     0     8    0
uvmvnodes   80     2078    0        0    43     0    43    43     0     8    0
vnodes     216     2078    0        0   116     0   116   116     0     8    0
namei      1024    7185    0     7181     4     2     2     2     0     8    1
kstatmem   264       42    0       18     2     0     2     2     0     8    0
scxspl     216    10482    0    10481     4     3     1     4     1     8    0
plimitpl   152       86    0       70     1     0     1     1     0     8    0
sigapl     424      659    0      613     6     0     6     6     0     8    0
futexpl     64     2217    0     2215     1     0     1     1     0     8    0
knotepl    120     7628    0     7578    10     0    10    10     0     8    7
kqueuepl   184       58    0       48     1     0     1     1     0     8    0
pipepl     288      137    0      110     3     0     3     3     0     8    0
fdescpl    432      642    0      613     4     0     4     4     0     8    0
filepl     120     2524    0     2270    10     0    10    10     0     8    1
lockfpl    104       70    0       66     1     0     1     1     0     8    0
lockfspl    48       36    0       32     1     0     1     1     0     8    0
sessionpl  144       29    0       21     1     0     1     1     0     8    0
pgrppl      48       47    0       31     1     0     1     1     0     8    0
ucredpl    104      201    0      189     1     0     1     1     0     8    0
zombiepl   144      703    0      700     2     1     1     1     0     8    0
processpl  1096     659    0      613     4     0     4     4     0     8    0
procpl     648      931    0      870     6     0     6     6     0     8    0
sockpl     504      513    0      477    14     1    13    13     0     8    8
mcl64k     65536      6    0        6     1     0     1     1     0     8    1
mcl16k     16384      5    0        5     1     0     1     1     0     8    1
mcl12k     12288      1    0        1     1     0     1     1     0     8    1
mcl9k      9216       1    0        1     1     0     1     1     0     8    1
mcl8k      8192      14    0       14     2     1     1     1     0     8    1
mcl4k      4096      11    0       11     2     1     1     1     0     8    1
mcl2k      2048    5344    0     5251    26    11    15    26     0     8    3
mtagpl      96       10    0        5     1     0     1     1     0     8    0
mbufpl     256     8395    0     8188    16     2    14    14     0     8    0
bufpl      280     4841    0       96   339     0   339   339     0     8    0
anonpl      24   187325    0   184134    54     4    50    50     0   187   29
amapchunkpl 152   15508    0    15003    31     0    31    31     0   158   10
amappl16   200     4924    0     4907     9     4     5     5     0     8    4
amappl15   192       11    0       11     1     1     0     1     0     8    0
amappl14   184      125    0      115     1     0     1     1     0     8    0
amappl13   176       11    0       11     1     1     0     1     0     8    0
amappl12   168     1397    0     1368     2     0     2     2     0     8    0
amappl11   160       49    0       39     1     0     1     1     0     8    0
amappl10   152        7    0        7     1     1     0     1     0     8    0
amappl9    144      137    0      137     1     1     0     1     0     8    0
amappl8    136       24    0       23     1     0     1     1     0     8    0
amappl7    128      113    0      103     1     0     1     1     0     8    0
amappl6    120      261    0      260     1     0     1     1     0     8    0
amappl5    112      171    0      162     1     0     1     1     0     8    0
amappl4    104      305    0      289     1     0     1     1     0     8    0
amappl3     96     2864    0     2750     4     0     4     4     0     8    1
amappl2     88      754    0      693     2     0     2     2     0     8    0
amappl1     80     8367    0     7854    13     1    12    12     0     8    1
amappl      88     4278    0     4102     5     0     5     5     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        7    0        1     1     0     1     1     0     8    0
uaddrrnd    24      642    0      613     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      642    0      613     1     0     1     1     0     8    0
vmmpekpl   168     6383    0     6332     3     0     3     3     0     8    0
vmmpepl    168    48569    0    46841    78     0    78    78     0   357    0
vmsppl     344      641    0      613     4     1     3     4     0     8    0
rwobjpl     24    20385    0    17455    18     0    18    18     0     8    0
pdppl      4096    1291    0     1226    99    32    67    75     0     8    2
pvpl        32   376569    0   367365   206     0   206   206     0   265  122
pmappl     216      641    0      613     2     0     2     2     0     8    0
extentpl    40       56    0       38     1     0     1     1     0     8    0
phpool     112      401    0       55    10     0    10    10     0     8    0
ddb> machine ddbcpu 0
No such command
ddb> trace
uao_detach(fffffd807e14bc60) at uao_detach+0xb9 sys/uvm/uvm_aobj.c:824
shm_deallocate_segment(fffffd8075cefa80) at shm_deallocate_segment+0x43 sys/kern/sysv_shm.c:152
sys_shmat(ffff80002a48d458,ffff800037679c40,ffff800037679b90) at sys_shmat+0x573 sys/kern/sysv_shm.c:278
syscall(ffff800037679c40) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x4b6d7dc4380, count: -5
ddb> machine ddbcpu 1
No such command
ddb> trace
uao_detach(fffffd807e14bc60) at uao_detach+0xb9 sys/uvm/uvm_aobj.c:824
shm_deallocate_segment(fffffd8075cefa80) at shm_deallocate_segment+0x43 sys/kern/sysv_shm.c:152
sys_shmat(ffff80002a48d458,ffff800037679c40,ffff800037679b90) at sys_shmat+0x573 sys/kern/sysv_shm.c:278
syscall(ffff800037679c40) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x4b6d7dc4380, count: -5

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/26 12:18 openbsd 9119eb3a9696 9314348a .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-main uvm_fault: uao_detach
* Struck through repros no longer work on HEAD.