syzbot


openbsd test error: uvm_fault: spllower

Status: fixed on 2020/12/09 20:34
Reported-by: syzbot+6fbdde8cabece10947ed@syzkaller.appspotmail.com
Fix commit: 3ba77c9295b2 Revert previous extension of the SCHED_LOCK(), the state isn't passed down.
First crash: 729d, last: 729d

Sample crash report:
login: uvm_fault(0xfffffd806bc01330, 0x6f1cf5b0, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      spllower+0x27:  movq    cpu_info_full_primary+0x25b0(,%rax,8),%r13
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
kernel page fault
uvm_fault(0xfffffd806bc01330, 0x6f1cf5b0, 0, 1) -> e
spllower(ffff80001d952000) at spllower+0x27 sys/arch/amd64/amd64/intr.c:716
end trace frame: 0xffff80001e957100, count: 0
ddb> trace
spllower(ffff80001d952000) at spllower+0x27 sys/arch/amd64/amd64/intr.c:716
single_thread_check_locked(ffff8000ffff87b8,0) at single_thread_check_locked+0x16a sys/kern/kern_sig.c:1971
userret(ffff8000ffff87b8) at userret+0x2d5 single_thread_check sys/kern/kern_sig.c:1991 [inline]
userret(ffff8000ffff87b8) at userret+0x2d5 sys/kern/kern_sig.c:1936
syscall(ffff80001e957230) at syscall+0x429 mi_syscall_return sys/sys/syscall_mi.h:129 [inline]
syscall(ffff80001e957230) at syscall+0x429 sys/arch/amd64/amd64/trap.c:612
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xbb4eaca900, count: -5
ddb> show registers
rdi               0xffff80001d952000
rsi                            0x40d
rbp               0xffff80001e9570a0
rbx                           0x1000    __ALIGN_SIZE
rdx               0xffff80001d952000
rcx                            0x40c
rax                       0x1d952000
r8                0xffffffff81d7fd16    setrunnable+0x76
r9                               0x5
r10               0x1240e118c092cc6f
r11               0x27061cf22893e487
r12               0xffff80001d8b1c38
r13                              0x1
r14               0xffff80001d8b1b30
r15                       0x1d952000
rip               0xffffffff81902ce7    spllower+0x27
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff80001e957060
ss                              0x10
spllower+0x27:  movq    cpu_info_full_primary+0x25b0(,%rax,8),%r13
ddb> show proc
PROC (syz-executor.0) pid=278606 stat=onproc
    flags process=1000<SINGLEEXIT> proc=4080000<SUSPSINGLE,THREAD>
    pri=32, usrpri=50, nice=20
    forw=0xffffffffffffffff, list=0xffff8000ffff8a48,0xffffffff82824790
    process=0xffff80001d8b1b30 user=0xffff80001e952000, vmspace=0xfffffd806bc01330
    estcpu=36, cpticks=0, pctcpu=0.0
    user=0, sys=0, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 66629   74971  97191      0  2      0x3000                syz-executor.0
*66629  278606  97191      0  7   0x4081000                syz-executor.0
 97191   49786   6254      0  3        0x82  nanosleep     syz-executor.0
  6254  303361  70044      0  3        0x82  thrsleep      syz-fuzzer
  6254  318451  70044      0  3   0x4000082  thrsleep      syz-fuzzer
  6254  343077  70044      0  3   0x4000082  thrsleep      syz-fuzzer
  6254  186642  70044      0  3   0x4000082  thrsleep      syz-fuzzer
  6254  296124  70044      0  3   0x4000082  thrsleep      syz-fuzzer
  6254    4172  70044      0  3   0x4000082  kqread        syz-fuzzer
 70044  271215  23810      0  3    0x10008a  pause         ksh
 23810  397958  26935      0  3        0x92  select        sshd
 19481  221495      1      0  3    0x100083  ttyin         getty
 26935  233475      1      0  3        0x80  select        sshd
 45580  345289  90323     73  3    0x100090  kqread        syslogd
 90323  338400      1      0  3    0x100082  netio         syslogd
 22356   89814      1     77  3    0x100090  poll          dhclient
 40700  173267      1      0  3        0x80  poll          dhclient
 51451  227476      0      0  3     0x14200  bored         smr
 75212   71622      0      0  2     0x14200                zerothread
 99786  446717      0      0  3     0x14200  aiodoned      aiodoned
 57039  508525      0      0  3     0x14200  syncer        update
 24519  405990      0      0  3     0x14200  cleaner       cleaner
 58042  143025      0      0  3     0x14200  reaper        reaper
 17410  273143      0      0  3     0x14200  pgdaemon      pagedaemon
 75732  298553      0      0  3     0x14200  bored         crynlk
  8102  231696      0      0  3     0x14200  bored         crypto
 16934   18387      0      0  3  0x40014200  acpi0         acpi0
 24754  367069      0      0  3     0x14200  bored         softnet
 41506   30985      0      0  3     0x14200  bored         systqmp
 68410  198350      0      0  3     0x14200  bored         systq
 87202  359814      0      0  3  0x40014200  bored         softclock
 14827    8412      0      0  3  0x40014200                idle0
     1  210606      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  9443   6321K    6321K  78643K     10540        0
            pcb    13      8K       8K  78643K        13        0
         rtable    83      2K       2K  78643K       153        0
         ifaddr    32      8K       8K  78643K        32        0
       counters    20     16K      16K  78643K        20        0
       ioctlops     0      0K       2K  78643K        14        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1199     75K      75K  78643K      1204        0
      UFS quota     1     32K      32K  78643K         1        0
      UFS mount     5     36K      36K  78643K         5        0
            shm     2      1K       1K  78643K         2        0
         VM map     2      0K       0K  78643K         2        0
            sem     2      0K       0K  78643K         2        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1809    195K     288K  78643K     12938        0
      file desc     3      8K      12K  78643K        18        0
           proc    47     38K      54K  78643K       324        0
        subproc    16      1K       1K  78643K        17        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
       in_multi    22      1K       1K  78643K        22        0
    ether_multi     1      0K       0K  78643K         1        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    19     95K      95K  78643K        19        0
           exec     0      0K       2K  78643K       295        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    52     10K      11K  78643K       598        0
       UVM aobj     3      2K       2K  78643K         3        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
            NDP     6      0K       0K  78643K         6        0
           temp    40   3950K    4013K  78643K      1663        0
         kqueue     3      4K       4K  78643K         3        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
arp         64        4    0        0     1     0     1     1     0     8    0
rtpcb      120       17    0       15     1     0     1     1     0     8    0
rtentry    112       34    0        1     1     0     1     1     0     8    0
unpcb      120       23    0       15     1     0     1     1     0     8    0
syncache   296        4    0        4     1     0     1     1     0     8    1
tcpcb      736       10    0        4     1     0     1     1     0     8    0
inpcb      296       28    0       22     1     0     1     1     0     8    0
nd6         48        3    0        0     1     0     1     1     0     8    0
kcovpl      48        1    0        0     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      145    0        0    10     0    10    10     0     8    0
art_table   32      146    0        0     2     0     2     2     0     8    0
art_node    16       33    0        3     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1412    0       21    87     0    87    87     0     8    0
ffsino     240     1412    0       21    82     0    82    82     0     8    0
nchpl      144     1627    0       36    59     0    59    59     0     8    0
uvmvnodes   72     1438    0        0    27     0    27    27     0     8    0
vnodes     208     1438    0        0    76     0    76    76     0     8    0
namei      1024    3827    0     3827     1     0     1     1     0     8    1
scxspl     216     4652    0     4652     1     0     1     1     0     8    1
plimitpl   152       13    0        7     1     0     1     1     0     8    0
sigapl     424      209    0      182     4     0     4     4     0     8    0
futexpl     56        3    0        3     1     0     1     1     0     8    1
knotepl    112       62    0       50     1     0     1     1     0     8    0
kqueuepl   152        2    0        0     1     0     1     1     0     8    0
pipepl     272       69    0       61     1     0     1     1     0     8    0
fdescpl    432      195    0      182     2     0     2     2     0     8    0
filepl     120      920    0      849     3     0     3     3     0     8    0
lockfpl    104        5    0        4     1     0     1     1     0     8    0
lockfspl    48        3    0        2     1     0     1     1     0     8    0
sessionpl  144       16    0        7     1     0     1     1     0     8    0
pgrppl      48       16    0        7     1     0     1     1     0     8    0
ucredpl     96       48    0       41     1     0     1     1     0     8    0
zombiepl   144      182    0      182     1     0     1     1     0     8    1
processpl  992      209    0      182     4     0     4     4     0     8    0
procpl     656      215    0      182     3     0     3     3     0     8    0
sockpl     400       68    0       52     2     0     2     2     0     8    0
mcl4k      4096       8    0        8     1     0     1     1     0     8    1
mcl2k      2048    9265    0     9226     8     1     7     8     0     8    1
mtagpl      96        2    0        2     1     1     0     1     0     8    0
mbufpl     256    15599    0    15520     6     0     6     6     0     8    0
bufpl      280     3440    0      169   234     0   234   234     0     8    0
anonpl      16    22194    0    20129    16     2    14    14     0   107    3
amapchunkpl 152     791    0      722     6     1     5     5     0   158    1
amappl16   192      150    0       92     3     0     3     3     0     8    0
amappl15   184        1    0        0     1     0     1     1     0     8    0
amappl14   176       22    0       19     1     0     1     1     0     8    0
amappl13   168       23    0       19     1     0     1     1     0     8    0
amappl12   160       10    0        8     1     0     1     1     0     8    0
amappl11   152       43    0       33     1     0     1     1     0     8    0
amappl10   144        3    0        1     1     0     1     1     0     8    0
amappl9    136      381    0      379     1     0     1     1     0     8    0
amappl8    128       78    0       64     1     0     1     1     0     8    0
amappl7    120      202    0      196     1     0     1     1     0     8    0
amappl6    112       53    0       44     1     0     1     1     0     8    0
amappl5    104      332    0      315     1     0     1     1     0     8    0
amappl4     96      237    0      216     1     0     1     1     0     8    0
amappl3     88      107    0       99     1     0     1     1     0     8    0
amappl2     80      822    0      765     2     0     2     2     0     8    0
amappl1     72    13562    0    13138    24     6    18    18     0     8    8
amappl      80      406    0      379     1     0     1     1     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       18    0       17     1     0     1     1     0     8    0
aobjpl      64        2    0        0     1     0     1     1     0     8    0
uaddrrnd    24      195    0      182     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      195    0      182     1     0     1     1     0     8    0
vmmpekpl   168     5643    0     5627     1     0     1     1     0     8    0
vmmpepl    168    29586    0    28557    77     5    72    72     0   357   27
vmsppl     272      194    0      182     1     0     1     1     0     8    0
pdppl      4096     396    0      364    46    10    36    36     0     8    4
pvpl        32   108550    0   103708   116     0   116   116     0   265   76
pmappl     200      194    0      182     1     0     1     1     0     8    0
extentpl    40       54    0       37     1     0     1     1     0     8    0
phpool     112      252    0       13     7     0     7     7     0     8    0
ddb> machine ddbcpu 0
No such command
ddb> trace
spllower(ffff80001d952000) at spllower+0x27 sys/arch/amd64/amd64/intr.c:716
single_thread_check_locked(ffff8000ffff87b8,0) at single_thread_check_locked+0x16a sys/kern/kern_sig.c:1971
userret(ffff8000ffff87b8) at userret+0x2d5 single_thread_check sys/kern/kern_sig.c:1991 [inline]
userret(ffff8000ffff87b8) at userret+0x2d5 sys/kern/kern_sig.c:1936
syscall(ffff80001e957230) at syscall+0x429 mi_syscall_return sys/sys/syscall_mi.h:129 [inline]
syscall(ffff80001e957230) at syscall+0x429 sys/arch/amd64/amd64/trap.c:612
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xbb4eaca900, count: -5
ddb> machine ddbcpu 1
No such command
ddb> trace
spllower(ffff80001d952000) at spllower+0x27 sys/arch/amd64/amd64/intr.c:716
single_thread_check_locked(ffff8000ffff87b8,0) at single_thread_check_locked+0x16a sys/kern/kern_sig.c:1971
userret(ffff8000ffff87b8) at userret+0x2d5 single_thread_check sys/kern/kern_sig.c:1991 [inline]
userret(ffff8000ffff87b8) at userret+0x2d5 sys/kern/kern_sig.c:1936
syscall(ffff80001e957230) at syscall+0x429 mi_syscall_return sys/sys/syscall_mi.h:129 [inline]
syscall(ffff80001e957230) at syscall+0x429 sys/arch/amd64/amd64/trap.c:612
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xbb4eaca900, count: -5

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-openbsd-main 2020/12/03 00:17 openbsd cbb32f9c11ef 8c9190ef .config log report
ci-openbsd-main 2020/12/03 00:17 openbsd cbb32f9c11ef 8c9190ef .config log report
ci-openbsd-main 2020/12/03 00:17 openbsd cbb32f9c11ef 8c9190ef .config log report
ci-openbsd-main 2020/12/02 23:49 openbsd 1ea95950577f 8c9190ef .config log report
ci-openbsd-main 2020/12/02 23:49 openbsd 1ea95950577f 8c9190ef .config log report
ci-openbsd-main 2020/12/02 23:49 openbsd 1ea95950577f 8c9190ef .config log report
* Struck through repros no longer work on HEAD.