syzbot


uvm_fault: strlen

Status: auto-closed as invalid on 2020/12/15 13:04
Reported-by: syzbot+ff4b7a0091a650f3c5f8@syzkaller.appspotmail.com
First crash: 1527d, last: 1527d

Sample crash report:
uvm_fault(0xfffffd807efffa10, 0x0, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      strlen+0x81:    movq    0(%rax),%rdx
ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
kernel page fault
uvm_fault(0xfffffd807efffa10, 0x0, 0, 1) -> e
strlen() at strlen+0x81
end trace frame: 0xffff800024112100, count: 0
ddb{1}> trace
strlen() at strlen+0x81
kern_sysctl(ffff800024112124,7,0,ffff800024112158,0,0) at kern_sysctl+0xc74 sys/kern/kern_sysctl.c:518
sys_sysctl(ffff800020e9e018,ffff8000241121c8,ffff800024112210) at sys_sysctl+0x209 sys/kern/kern_sysctl.c:250
syscall(ffff800024112290) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800024112290) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:568
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bbe949cc60, count: -5
ddb{1}> show registers
rdi                              0x5
rsi                              0x1
rbp               0xffff800024111dd0
rbx                              0x5
rdx               0xffff800021cf7000
rcx                            0x128
rax                                0
r8                 0x101010101010101
r9                0x8080808080808080
r10               0xe49c4ea53864be7e
r11               0x4bd91826425b47e8
r12                                0
r13                            0x19e
r14                            0x240
r15               0xffff800024112158
rip               0xffffffff814bc9e1    strlen+0x81
cs                               0x8
rflags                       0x10206    __ALIGN_SIZE+0xf206
rsp               0xffff800024111cf8
ss                              0x10
strlen+0x81:    movq    0(%rax),%rdx
ddb{1}> show proc
PROC (syz-executor.0) pid=140097 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=32, usrpri=86, nice=20
    forw=0xffffffffffffffff, list=0xffff800020e9e290,0xffffffff82888b38
    process=0xffff800020eccfc8 user=0xffff80002410d000, vmspace=0xfffffd807efffa10
    estcpu=36, cpticks=0, pctcpu=0.0
    user=0, sys=0, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 51763    4270   6320      0  7           0                syz-executor.0
*51763  140097   6320      0  7   0x4000000                syz-executor.0
 74288  124974      0      0  3     0x14200  acct          acct
  6320   63774  56034      0  3        0x82  nanosleep     syz-executor.0
 92569  217652  56034      0  3         0x2  biowait       syz-executor.1
 15691  475934      0      0  3     0x14200  bored         sosplice
 56034    4123  66339      0  3        0x82  thrsleep      syz-fuzzer
 56034  180637  66339      0  3   0x4000082  nanosleep     syz-fuzzer
 56034  420289  66339      0  3   0x4000082  thrsleep      syz-fuzzer
 56034  477690  66339      0  3   0x4000082  thrsleep      syz-fuzzer
 56034  411795  66339      0  3   0x4000082  nanosleep     syz-fuzzer
 56034  346764  66339      0  3   0x4000082  kqread        syz-fuzzer
 56034  157623  66339      0  3   0x4000082  thrsleep      syz-fuzzer
 56034  324654  66339      0  3   0x4000082  thrsleep      syz-fuzzer
 66339  149080  20213      0  3    0x10008a  pause         ksh
 20213  431903  15179      0  3        0x92  select        sshd
  3639  470219      1      0  3    0x100083  ttyin         getty
 15179  200786      1      0  3        0x80  select        sshd
 23271  118201  51194     74  3    0x100092  bpf           pflogd
 51194  458136      1      0  3        0x80  netio         pflogd
 62471   15758  75031     73  3    0x100090  kqread        syslogd
 75031  396149      1      0  3    0x100082  netio         syslogd
 73947  266829      1     77  3    0x100090  poll          dhclient
 18146  514828      1      0  3        0x80  poll          dhclient
 32038   62610      0      0  3     0x14200  bored         smr
 51614  246733      0      0  3     0x14200  pgzero        zerothread
 89485  151511      0      0  3     0x14200  aiodoned      aiodoned
  1973  225738      0      0  3     0x14200  syncer        update
 91234  308954      0      0  3     0x14200  cleaner       cleaner
 42093  133610      0      0  3     0x14200  reaper        reaper
 11053  479665      0      0  3     0x14200  pgdaemon      pagedaemon
 30388  502915      0      0  3     0x14200  bored         crynlk
 99474  149020      0      0  3     0x14200  bored         crypto
 69263  290568      0      0  3  0x40014200  acpi0         acpi0
 71420  371142      0      0  3  0x40014200                idle1
 95187  130829      0      0  3     0x14200  bored         softnet
 31445   10603      0      0  3     0x14200  bored         systqmp
 68334   32577      0      0  3     0x14200  bored         systq
 63986  306044      0      0  3  0x40014200  bored         softclock
 23118  504498      0      0  3  0x40014200                idle0
     1  403111      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 51763 (syz-executor.0) thread 0xffff800020e9e018 (140097)
exclusive rwlock sysctlklk r = 0 (0xffffffff8271e3e0)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1164
#1  rw_enter+0x446 sys/kern/kern_rwlock.c:311
#2  sysctl_malloc+0x1e7 sys/kern/kern_malloc.c:652
#3  kern_sysctl+0xc74 sys/kern/kern_sysctl.c:518
#4  sys_sysctl+0x209 sys/kern/kern_sysctl.c:250
#5  syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#5  syscall+0x4a1 sys/arch/amd64/amd64/trap.c:568
#6  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff82888d68)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1164
#1  syscall+0x3fd mi_syscall sys/sys/syscall_mi.h:93 [inline]
#1  syscall+0x3fd sys/arch/amd64/amd64/trap.c:568
#2  Xsyscall+0x128
Process 92569 (syz-executor.1) thread 0xffff800020e9f8c8 (217652)
exclusive rrwlock inode r = 0 (0xfffffd806e8102b8)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1164
#1  rw_enter+0x446 sys/kern/kern_rwlock.c:311
#2  rrw_enter+0x88 sys/kern/kern_rwlock.c:462
#3  ufs_ihashins+0x45 sys/ufs/ufs/ufs_ihash.c:140
#4  ffs_vget+0x135 sys/ufs/ffs/ffs_vfsops.c:1350
#5  ffs_inode_alloc+0x1e1 sys/ufs/ffs/ffs_alloc.c:394
#6  ufs_mkdir+0xf4 sys/ufs/ufs/ufs_vnops.c:1162
#7  VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450
#8  domkdirat+0x121 sys/kern/vfs_syscalls.c:3046
#9  syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#9  syscall+0x4a1 sys/arch/amd64/amd64/trap.c:568
#10 Xsyscall+0x128
exclusive rrwlock inode r = 0 (0xfffffd806ae59a28)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1164
#1  rw_enter+0x446 sys/kern/kern_rwlock.c:311
#2  rrw_enter+0x88 sys/kern/kern_rwlock.c:462
#3  VOP_LOCK+0x4b sys/kern/vfs_vops.c:603
#4  vn_lock+0x6c sys/kern/vfs_vnops.c:575
#5  vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419
#6  namei+0x5f7 sys/kern/vfs_lookup.c:249
#7  domkdirat+0x75 sys/kern/vfs_syscalls.c:3031
#8  syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#8  syscall+0x4a1 sys/arch/amd64/amd64/trap.c:568
#9  Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9525   6419K    7578K  78643K     15098        0
            pcb    13      8K       8K  78643K       259        0
         rtable   123      7K       9K  78643K      1084        0
         ifaddr    77     15K      15K  78643K       359        0
       counters    43     33K      34K  78643K       121        0
       ioctlops     0      0K       4K  78643K      1775        0
            iov     0      0K      16K  78643K       157        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1224     77K      77K  78643K      2644        0
      UFS quota     1     32K      32K  78643K         1        0
      UFS mount     5     36K      36K  78643K         5        0
            shm     2      1K       9K  78643K        30        0
         VM map     2      1K       1K  78643K         2        0
            sem    12      0K       0K  78643K       490        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1824    197K     290K  78643K     13058        0
      file desc     5     13K      25K  78643K      4126        0
          sigio     0      0K       0K  78643K         5        0
           proc    63     63K      95K  78643K       882        0
        subproc    32      2K       2K  78643K        68        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
    ip_moptions     0      0K       0K  78643K       281        0
       in_multi    33      2K       2K  78643K       244        0
    ether_multi     1      0K       0K  78643K        43        0
            mrt     0      0K       0K  78643K        77        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    67    307K     307K  78643K        67        0
           exec     0      0K       2K  78643K       528        0
     pfkey data     0      0K       0K  78643K         5        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   158     29K      43K  78643K     10328        0
       UVM aobj    36      2K       2K  78643K        46        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
    ip6_options     0      0K       0K  78643K       159        0
            NDP    13      0K       0K  78643K        71        0
           temp   135   3964K    4029K  78643K     65938        0
         kqueue     3      4K      16K  78643K       193        0
      SYN cache     2     16K      16K  78643K         2        0
ddb{1}> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp         64       10    0        4     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       96      121    0      119     1     0     1     1     0     8    0
rtentry    112      107    0       63     2     0     2     2     0     8    0
unpcb      120     1016    0     1002     1     0     1     1     0     8    0
syncache   272       63    0       63     5     5     0     1     0     8    0
tcpqe       32       47    0       47     4     4     0     1     0     8    0
tcpcb      592      840    0      824    14    12     2     5     0     8    0
inpcb      296     2035    0     2028     6     4     2     3     0     8    1
rttmr       72       29    0       29     3     3     0     1     0     8    0
nd6         48       23    0       17     1     0     1     1     0     8    0
pkpcb       40       49    0       49     5     5     0     1     0     8    0
kcovpl      48        4    0        2     1     0     1     1     0     8    0
ppxss      1128       4    0        4     1     1     0     1     0     8    0
pffrag     232       10    0       10     2     2     0     1     0   482    0
pffrnode    88       10    0       10     2     2     0     1     0     8    0
pffrent     40       20    0       20     2     2     0     1     0     8    0
pfosfp      40      850    0      423     5     0     5     5     0     8    0
pfosfpen   112     1461    0      714    22     0    22    22     0     8    0
pfrktable  1344     162    0      155     1     0     1     1     0     8    0
pftag       88        4    0        4     1     1     0     1     0     8    0
pfstitem    24       12    0       10     1     0     1     1     0     8    0
pfstkey    112       12    0       10     1     0     1     1     0     8    0
pfstate    328       12    0       10     1     0     1     1     0     8    0
pfrule     1360      74    0       59     3     1     2     2     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      279    0       88    12     0    12    12     0     8    0
art_table   32      280    0       88     2     0     2     2     0     8    0
art_node    16      106    0       66     1     0     1     1     0     8    0
sysvmsgpl   40       34    0       11     1     0     1     1     0     8    0
semapl     112      488    0      478     1     0     1     1     0     8    0
shmpl      112       43    0       10     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     6492    0     5086    89     0    89    89     0     8    0
ffsino     272     6492    0     5086    94     0    94    94     0     8    0
nchpl      144    11654    0    10064    60     0    60    60     0     8    0
uvmvnodes   72     5926    0        0   108     0   108   108     0     8    0
vnodes     208     5926    0        0   312     0   312   312     0     8    0
namei      1024   29068    0    29067     1     0     1     1     0     8    0
percpumem   16       71    0       39     1     0     1     1     0     8    0
vmpool     560       21    0       21     3     3     0     1     0     8    0
pfiaddrpl  120       57    0       42     1     0     1     1     0     8    0
scxspl     200    34374    0    34373    13    12     1     7     0     8    0
plimitpl   152      168    0      160     1     0     1     1     0     8    0
sigapl     424     4337    0     4304     4     0     4     4     0     8    0
futexpl     56    32457    0    32457     1     0     1     1     0     8    1
knotepl    112      271    0      251     1     0     1     1     0     8    0
kqueuepl   152     2017    0     2008     1     0     1     1     0     8    0
pipepl     304      244    0      233    12    10     2     2     0     8    1
fdescpl    496     4320    0     4304     3     0     3     3     0     8    0
filepl     152    15411    0    15309     5     0     5     5     0     8    1
lockfpl    104      479    0      478     1     0     1     1     0     8    0
lockfspl    48      204    0      203     1     0     1     1     0     8    0
sessionpl  120       20    0        9     1     0     1     1     0     8    0
pgrppl      48       38    0       27     1     0     1     1     0     8    0
ucredpl     96     2066    0     2057     1     0     1     1     0     8    0
zombiepl   144     4304    0     4304     1     0     1     1     0     8    1
processpl  1008    4337    0     4304     5     0     5     5     0     8    0
procpl     632     9459    0     9418     4     0     4     4     0     8    0
sosppl     144       52    0       52     2     2     0     1     0     8    0
sockpl     400     3233    0     3210     6     2     4     5     0     8    0
mcl64k     65536     20    0        0     3     0     3     3     0     8    0
mcl16k     16384      6    0        0     1     0     1     1     0     8    0
mcl12k     12288     17    0        0     2     0     2     2     0     8    0
mcl9k      9216      15    0        0     2     0     2     2     0     8    0
mcl8k      8192      17    0        0     3     0     3     3     0     8    0
mcl4k      4096      24    0        0     3     0     3     3     0     8    0
mcl2k2     2112       3    0        0     1     0     1     1     0     8    0
mcl2k      2048     291    0        0    19     0    19    19     0     8    0
mtagpl      96      239    0        0     5     0     5     5     0     8    0
mbufpl     256      953    0        0    56     1    55    55     0     8    0
bufpl      280     9810    0     3535   449     0   449   449     0     8    0
anonpl      16   297385    0   289747    35     3    32    32     0   124    0
amapchunkpl 152   15821    0    15617    11     2     9     9     0   158    0
amappl16   192    12533    0    12271    15     1    14    15     0     8    0
amappl15   184       10    0        8     1     0     1     1     0     8    0
amappl14   176        9    0        3     2     1     1     1     0     8    0
amappl13   168      106    0      104     1     0     1     1     0     8    0
amappl12   160     1291    0     1286     1     0     1     1     0     8    0
amappl11   152       71    0       56     1     0     1     1     0     8    0
amappl10   144     1593    0     1587     1     0     1     1     0     8    0
amappl9    136     1557    0     1557     1     1     0     1     0     8    0
amappl8    128     1480    0     1396     3     0     3     3     0     8    0
amappl7    120     1877    0     1866     1     0     1     1     0     8    0
amappl6    112      144    0      125     1     0     1     1     0     8    0
amappl5    104     5710    0     5699     1     0     1     1     0     8    0
amappl4     96      348    0      315     1     0     1     1     0     8    0
amappl3     88      219    0      213     1     0     1     1     0     8    0
amappl2     80    29643    0    29572     3     1     2     3     0     8    0
amappl1     72   119474    0   119010    24    14    10    19     0     8    0
amappl      80     9787    0     9727     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       18    0       17     1     0     1     1     0     8    0
aobjpl      64       45    0       10     1     0     1     1     0     8    0
uaddrrnd    24     4341    0     4325     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24     4341    0     4325     1     0     1     1     0     8    0
vmmpekpl   168    21366    0    21326     3     0     3     3     0     8    0
vmmpepl    168   526363    0   524855    93    20    73    75     0   357    3
vmsppl     368     4340    0     4325     2     0     2     2     0     8    0
pdppl      4096    8689    0     8650     6     0     6     6     0     8    1
pvpl        32  1429354    0  1418527   160    65    95   115     0   265    5
pmappl     232     4340    0     4325     5     4     1     2     0     8    0
extentpl    40       53    0       36     1     0     1     1     0     8    0
phpool     112      309    0       11     9     0     9     9     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x1a:        addq    $0x8,%rsp
ddb{0}> trace
x86_ipi_db(ffffffff826d0ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x37 kd_curproc sys/dev/kcov.c:513 [inline]
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x37 sys/dev/kcov.c:121
__mp_lock(ffffffff82888b60) at __mp_lock+0x133 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82888b60) at __mp_lock+0x133 sys/kern/kern_lock.c:147
intr_handler(ffff800021cee400,ffff80000004a400) at intr_handler+0x5e sys/arch/amd64/amd64/intr.c:532
Xintr_ioapic_edge17_untramp() at Xintr_ioapic_edge17_untramp+0x19f
end of kernel
end trace frame: 0x7f7fffffadb0, count: -7
ddb{0}> machine ddbcpu 1
Stopped at      strlen+0x81:    movq    0(%rax),%rdx
ddb{1}> trace
strlen() at strlen+0x81
kern_sysctl(ffff800024112124,7,0,ffff800024112158,0,0) at kern_sysctl+0xc74 sys/kern/kern_sysctl.c:518
sys_sysctl(ffff800020e9e018,ffff8000241121c8,ffff800024112210) at sys_sysctl+0x209 sys/kern/kern_sysctl.c:250
syscall(ffff800024112290) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800024112290) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:568
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7bbe949cc60, count: -5

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/16 13:03 openbsd cd7ceac03ec9 77507d02 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.