syzbot


uvm_fault: in6ifa_ifpforlinklocal

Status: fixed on 2020/08/05 06:16
Reported-by: syzbot+62af76d8cb7c09ac017c@syzkaller.appspotmail.com
Fix commit: efa3c3dd644f Validate input given to ioctl(SIOCAIFADDR_IN6) like NetBSD already does. Fixes a bunch of panics reported by syzkaller.
First crash: 1625d, last: 1625d

Sample crash report:
uvm_fault(0xfffffd807a2a2d00, 0x1, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      in6ifa_ifpforlinklocal+0x48:    movzbl  0x1(%r13),%r12d
ddb{0}> 
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
kernel page fault
uvm_fault(0xfffffd807a2a2d00, 0x1, 0, 1) -> e
in6ifa_ifpforlinklocal(ffff800000ac3000,0) at in6ifa_ifpforlinklocal+0x48 sys/netinet6/in6.c:1169
end trace frame: 0xffff800023112db0, count: 0
ddb{0}> trace
in6ifa_ifpforlinklocal(ffff800000ac3000,0) at in6ifa_ifpforlinklocal+0x48 sys/netinet6/in6.c:1169
in6_ifattach(ffff800000ac3000) at in6_ifattach+0x160 sys/netinet6/in6_ifattach.c:393
in6_ioctl_change_ifaddr(8080691a,ffff800023112f70,ffff800000ac3000) at in6_ioctl_change_ifaddr+0x3de sys/netinet6/in6.c:349
ifioctl(fffffd806f67c4b0,8080691a,ffff800023112f70,ffff800020e13d60) at ifioctl+0xe70 sys/net/if.c:2288
soo_ioctl(fffffd806ca3e600,8080691a,ffff800023112f70,ffff800020e13d60) at soo_ioctl+0x27c sys/kern/sys_socket.c:138
sys_ioctl(ffff800020e13d60,ffff800023113088,ffff8000231130d0) at sys_ioctl+0x4a5
syscall(ffff800023113150) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800023113150) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x156822ec480, count: -8
ddb{0}> show registers
rdi               0xffffffff8134c085    in6ifa_ifpforlinklocal+0x45
rsi                             0xe6
rbp               0xffff800023112d60
rbx                              0x6
rdx                             0xe7
rcx               0xffff800020ef0000
rax               0xffff800020ef0000
r8                0xffffffff817241dd    in6_ifattach+0x3d
r9                               0x1
r10                              0x4
r11               0x1a7d5870ff605693
r12                              0x2
r13                                0
r14               0xffff800000b0c000
r15                                0
rip               0xffffffff8134c088    in6ifa_ifpforlinklocal+0x48
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff800023112d20
ss                              0x10
in6ifa_ifpforlinklocal+0x48:    movzbl  0x1(%r13),%r12d
ddb{0}> show proc
PROC (syz-executor.0) pid=181350 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=32, usrpri=80, nice=20
    forw=0xffffffffffffffff, list=0xffff800020e13af0,0xffffffff828f7770
    process=0xffff800020ede040 user=0xffff80002310e000, vmspace=0xfffffd807a2a2d00
    estcpu=36, cpticks=0, pctcpu=0.0
    user=0, sys=0, intr=0
ddb{0}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 48725  129614  47891      0  2           0                syz-executor.0
*48725  181350  47891      0  7   0x4000000                syz-executor.0
 59964    1940      0      0  3     0x14280  nfsidl        nfsio
 44558   74386      0      0  3     0x14280  nfsidl        nfsio
 76018   16635      0      0  3     0x14280  nfsidl        nfsio
 89713  302339      0      0  3     0x14280  nfsidl        nfsio
 35238  250775      0      0  3     0x14280  nfsidl        nfsio
 73545  151155      0      0  3     0x14280  nfsidl        nfsio
 36617   94394      0      0  3     0x14280  nfsidl        nfsio
 83518  513301      0      0  3     0x14280  nfsidl        nfsio
 69937    4902      0      0  3     0x14280  nfsidl        nfsio
  3054  426311      0      0  3     0x14280  nfsidl        nfsio
  4897  375208      0      0  3     0x14280  nfsidl        nfsio
 71700  281474      0      0  3     0x14280  nfsidl        nfsio
  4635  405065      0      0  3     0x14280  nfsidl        nfsio
 68357   18760      0      0  3     0x14280  nfsidl        nfsio
 30021  266711      0      0  3     0x14280  nfsidl        nfsio
 78648  227181      0      0  3     0x14280  nfsidl        nfsio
 53196  522097      0      0  3     0x14280  nfsidl        nfsio
 89633  119520      0      0  3     0x14280  nfsidl        nfsio
 69916  143170      0      0  3     0x14280  nfsidl        nfsio
 84245  501713      0      0  3     0x14280  nfsidl        nfsio
 51781  185882      0      0  3     0x14200  bored         sosplice
 49162  432627   5868      0  3        0x82  piperd        syz-executor.1
 47891  520079   5868      0  3        0x82  nanosleep     syz-executor.0
  5868  447768   9306      0  3        0x82  thrsleep      syz-fuzzer
  5868   26145   9306      0  3   0x4000082  nanosleep     syz-fuzzer
  5868   78298   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868  117608   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868    1854   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868  502021   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868  239945   9306      0  7   0x4000002                syz-fuzzer
  5868  265894   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868   69901   9306      0  3   0x4000082  thrsleep      syz-fuzzer
  5868  376840   9306      0  3   0x4000082  kqread        syz-fuzzer
  9306  194941  44781      0  3    0x10008a  pause         ksh
 44781  123404  10344      0  3        0x92  select        sshd
 21223   37216      1      0  3    0x100083  ttyin         getty
 10344  473424      1      0  3        0x80  select        sshd
 41583   29572  17126     74  3    0x100092  bpf           pflogd
 17126  489720      1      0  3        0x80  netio         pflogd
 58744   59911  49929     73  3    0x100090  kqread        syslogd
 49929  143351      1      0  3    0x100082  netio         syslogd
 14126   36758      1     77  3    0x100090  poll          dhclient
 35424  484618      1      0  3        0x80  poll          dhclient
 26507  425165      0      0  3     0x14200  bored         smr
 12065  497903      0      0  2     0x14200                zerothread
 79038  202770      0      0  3     0x14200  aiodoned      aiodoned
 63563  500973      0      0  3     0x14200  syncer        update
  4973  236706      0      0  3     0x14200  cleaner       cleaner
  6205  379830      0      0  3     0x14200  reaper        reaper
 65180  180590      0      0  3     0x14200  pgdaemon      pagedaemon
 54472  501359      0      0  3     0x14200  bored         crynlk
 50161  482008      0      0  3     0x14200  bored         crypto
 88636   57336      0      0  3  0x40014200  acpi0         acpi0
 19472   60364      0      0  3  0x40014200                idle1
 88346  295065      0      0  3     0x14200  bored         softnet
 62868  353527      0      0  3     0x14200  bored         systqmp
 13406  146970      0      0  3     0x14200  bored         systq
 96482  390581      0      0  3  0x40014200  bored         softclock
 59789  174367      0      0  3  0x40014200                idle0
     1  101364      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{0}> show all locks
Process 48725 (syz-executor.0) thread 0xffff800020e13d60 (181350)
exclusive rwlock netlock r = 0 (0xffffffff82723be8)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1  in6_ioctl_change_ifaddr+0x155 sys/netinet6/in6.c:295
#2  ifioctl+0xe70 sys/net/if.c:2288
#3  soo_ioctl+0x27c sys/kern/sys_socket.c:138
#4  sys_ioctl+0x4a5
#5  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#5  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#6  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff828f3518)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1  soo_ioctl+0x26a sys/kern/sys_socket.c:138
#2  sys_ioctl+0x4a5
#3  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#3  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#4  Xsyscall+0x128
ddb{0}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9527   6427K    7014K  78643K     11653        0
            pcb    13      8K       8K  78643K       156        0
         rtable   104      7K       9K  78643K       456        0
         ifaddr   103     21K      21K  78643K       207        0
         sysctl     2      0K       0K  78643K         2        0
       counters    43     33K      34K  78643K        69        0
       ioctlops     0      0K       4K  78643K      1604        0
            iov     0      0K      16K  78643K       109        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1223     77K      77K  78643K      1584        0
      UFS quota     1     32K      32K  78643K         1        0
      UFS mount     5     36K      36K  78643K         5        0
            shm     2      1K       5K  78643K        11        0
         VM map     2      1K       1K  78643K         2        0
            sem    12      1K       1K  78643K        63        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1824    197K     290K  78643K     13058        0
      file desc     5     13K      25K  78643K       738        0
          sigio     0      0K       0K  78643K        11        0
           proc    61     63K      95K  78643K       482        0
        subproc    32      2K       2K  78643K        34        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
    ip_moptions     0      0K       0K  78643K       102        0
       in_multi    96      4K       4K  78643K       192        0
    ether_multi     1      0K       0K  78643K        30        0
            mrt     0      0K       0K  78643K         4        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    43    201K     201K  78643K        43        0
           exec     0      0K       1K  78643K       259        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   137    104K     108K  78643K      3400        0
       UVM aobj    28      2K       2K  78643K        30        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
    ip6_options     0      0K       0K  78643K       124        0
            NDP    13      0K       0K  78643K        33        0
           temp   129   3858K    3922K  78643K     14280        0
         kqueue     3      4K       9K  78643K        41        0
      SYN cache     2     16K      16K  78643K         2        0
ddb{0}> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp         64        7    0        1     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       53    0       51     1     0     1     1     0     8    0
rtentry    112       68    0       34     2     0     2     2     0     8    0
unpcb      120      337    0      327     1     0     1     1     0     8    0
syncache   264        8    0        8     3     3     0     1     0     8    0
sackhl      24        1    0        1     1     1     0     1     0     8    0
tcpqe       32      153    0      153     2     2     0     1     0     8    0
tcpcb      544      800    0      796     1     0     1     1     0     8    0
ipq         40        1    0        1     1     1     0     1     0     8    0
ipqe        40        2    0        2     1     1     0     1     0     8    0
inpcb      280     1287    0     1278     5     4     1     2     0     8    0
rttmr       72        2    0        2     2     1     1     1     0     8    1
ip6q        72        1    0        1     1     1     0     1     0     8    0
ip6af       40        3    0        3     1     1     0     1     0     8    0
nd6         48       10    0        6     1     0     1     1     0     8    0
pkpcb       40        4    0        4     2     2     0     1     0     8    0
ppxss      1128       2    0        2     2     2     0     1     0     8    0
pfstscr     40        2    0        2     1     1     0     1     0     8    0
pffrag     232        7    0        7     4     4     0     1     0   482    0
pffrnode    88        7    0        7     4     4     0     1     0     8    0
pffrent     40      145    0      145     4     4     0     1     0     8    0
pfosfp      40      846    0      423     5     0     5     5     0     8    0
pfosfpen   112     1428    0      714    21     0    21    21     0     8    0
pfrktable  1344      50    0       42     1     0     1     1     0     8    0
pfstitem    24       18    0       16     1     0     1     1     0     8    0
pfstkey    112       18    0       16     1     0     1     1     0     8    0
pfstate    328       17    0       15     2     1     1     2     0     8    0
pfrule     1360      41    0       26     3     1     2     2     0     8    0
art_heap8  4096       2    0        0     2     0     2     2     0     8    0
art_heap4  256      350    0      177    14     3    11    13     0     8    0
art_table   32      352    0      177     2     0     2     2     0     8    0
art_node    16       67    0       38     1     0     1     1     0     8    0
sysvmsgpl   40       12    0       10     2     1     1     1     0     8    0
semupl     112        3    0        3     1     1     0     1     0     8    0
semapl     112       57    0       47     1     0     1     1     0     8    0
shmpl      112       28    0        2     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     2402    0     1000    88     0    88    88     0     8    0
ffsino     272     2402    0     1000    94     0    94    94     0     8    0
nchpl      144     3596    0     1988    60     0    60    60     0     8    0
uvmvnodes   72     2695    0        0    49     0    49    49     0     8    0
vnodes     208     2695    0        0   142     0   142   142     0     8    0
namei      1024    9962    0     9962     3     2     1     1     0     8    1
percpumem   16       45    0       13     1     0     1     1     0     8    0
vcpupl     1984      12    0        0     2     0     2     2     0     8    0
vmpool     560       19    0        7     1     0     1     1     0     8    0
pfiaddrpl  120       17    0       11     1     0     1     1     0     8    0
scxspl     192    11088    0    11088    11    10     1     7     0     8    1
plimitpl   152       85    0       77     1     0     1     1     0     8    0
sigapl     424      974    0      922     6     0     6     6     0     8    0
futexpl     56    13891    0    13891     3     2     1     1     0     8    1
knotepl    112      103    0       84     1     0     1     1     0     8    0
kqueuepl   144      457    0      451     1     0     1     1     0     8    0
pipelkpl    48      218    0      208     1     0     1     1     0     8    0
pipepl     120      436    0      417     3     2     1     2     0     8    0
fdescpl    496      938    0      922     3     0     3     3     0     8    0
filepl     152     6095    0     5993     6     1     5     5     0     8    1
lockfpl    104      125    0      124     1     0     1     1     0     8    0
lockfspl    48       44    0       43     1     0     1     1     0     8    0
sessionpl  112       18    0        7     1     0     1     1     0     8    0
pgrppl      48       24    0       13     1     0     1     1     0     8    0
ucredpl     96      549    0      540     1     0     1     1     0     8    0
zombiepl   144      922    0      922     2     1     1     1     0     8    1
processpl  984      974    0      922     9     2     7     7     0     8    0
procpl     624     2526    0     2464     6     0     6     6     0     8    1
sosppl     128       17    0       17     4     4     0     1     0     8    0
sockpl     400     1683    0     1662     4     1     3     4     0     8    0
mcl64k     65536     15    0        0     2     0     2     2     0     8    0
mcl16k     16384      2    0        0     1     0     1     1     0     8    0
mcl12k     12288      9    0        0     1     0     1     1     0     8    0
mcl9k      9216       3    0        0     1     0     1     1     0     8    0
mcl8k      8192       4    0        0     1     0     1     1     0     8    0
mcl4k      4096      11    0        0     2     0     2     2     0     8    0
mcl2k2     2112       3    0        0     1     0     1     1     0     8    0
mcl2k      2048     213    0        0    26     1    25    26     0     8    0
mtagpl      80       68    0        0     2     0     2     2     0     8    0
mbufpl     256      701    0        0    36     0    36    36     0     8    0
bufpl      280     4926    0      132   343     0   343   343     0     8    0
anonpl      16    97509    0    81309   104    37    67    80     0   124    0
amapchunkpl 152    5860    0     5719    26    18     8    20     0   158    0
amappl16   192     4473    0     3595    66    20    46    55     0     8    0
amappl15   184        2    0        0     1     0     1     1     0     8    0
amappl14   176       21    0       18     1     0     1     1     0     8    0
amappl13   168       42    0       37     1     0     1     1     0     8    0
amappl12   160       20    0       17     1     0     1     1     0     8    0
amappl11   152      759    0      742     1     0     1     1     0     8    0
amappl10   144       22    0       18     1     0     1     1     0     8    0
amappl9    136      388    0      387     1     0     1     1     0     8    0
amappl8    128      377    0      343     2     0     2     2     0     8    0
amappl7    120      117    0      106     1     0     1     1     0     8    0
amappl6    112      697    0      691     2     1     1     1     0     8    0
amappl5    104      820    0      802     1     0     1     1     0     8    0
amappl4     96      498    0      469     1     0     1     1     0     8    0
amappl3     88      137    0      131     1     0     1     1     0     8    0
amappl2     80     6399    0     6325     2     0     2     2     0     8    0
amappl1     72    28949    0    28506    23    13    10    18     0     8    0
amappl      80     2761    0     2713     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       29    0        2     1     0     1     1     0     8    0
uaddrrnd    24      957    0      929     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      957    0      929     1     0     1     1     0     8    0
vmmpekpl   168    11077    0    11038     2     0     2     2     0     8    0
vmmpepl    168   118250    0   116192   131    40    91   110     0   357    0
vmsppl     368      956    0      929     3     0     3     3     0     8    0
pdppl      4096    1921    0     1870    10     3     7     7     0     8    0
pvpl        32   299702    0   280757   262   104   158   190     0   265    5
pmappl     232      956    0      929     3     1     2     2     0     8    0
extentpl    40       53    0       36     1     0     1     1     0     8    0
phpool     112      301    0       13     9     0     9     9     0     8    0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
in6ifa_ifpforlinklocal(ffff800000ac3000,0) at in6ifa_ifpforlinklocal+0x48 sys/netinet6/in6.c:1169
in6_ifattach(ffff800000ac3000) at in6_ifattach+0x160 sys/netinet6/in6_ifattach.c:393
in6_ioctl_change_ifaddr(8080691a,ffff800023112f70,ffff800000ac3000) at in6_ioctl_change_ifaddr+0x3de sys/netinet6/in6.c:349
ifioctl(fffffd806f67c4b0,8080691a,ffff800023112f70,ffff800020e13d60) at ifioctl+0xe70 sys/net/if.c:2288
soo_ioctl(fffffd806ca3e600,8080691a,ffff800023112f70,ffff800020e13d60) at soo_ioctl+0x27c sys/kern/sys_socket.c:138
sys_ioctl(ffff800020e13d60,ffff800023113088,ffff8000231130d0) at sys_ioctl+0x4a5
syscall(ffff800023113150) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800023113150) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x156822ec480, count: -8
ddb{0}> machine ddbcpu 1
Stopped at      x86_ipi_db+0x1a:        addq    $0x8,%rsp
ddb{1}> trace
x86_ipi_db(ffff800020d80ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352
x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
end of kernel
end trace frame: 0xc0027a1580, count: -3

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/10 12:07 openbsd f42e19bebb12 860c4de9 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.