syzbot


panic:W ARpNoIoNlG_c:a ScPhLe _NiOtTe mL_OmWaEgRicED_ cOhNec kS:Y SmCbAuLfLp l 2c p51u6 5f0r5e4e2 3li sEXtI T mo0d ai

Status: closed as dup on 2020/04/08 06:32
Reported-by: syzbot+ea561ba7fd789ce551d5@syzkaller.appspotmail.com
First crash: 1690d, last: 1690d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
pool: cpu free list modified: mbufpl syz 15863 1570d 1856d

Sample crash report:
panic:W ARpNoIoNlG_c:a ScPhLe _NiOtTe mL_OmWaEgRicED_ cOhNec kS:Y SmCbAuLfLp l 2c p51u6 5f0r5e4e2 3li sEXtI T mo0d ai
fi
Stopped at      savectx+0xb1:   movl    $0,%gs:0x530
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 22718  38088      0         0x2          0    1  syz-executor.1
   7717  87418      0     0x14000      0x200    0  softnet
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffd0150, count: 14
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{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806d996f00+16 0x0!=0x43799f272346bc21
ddb{1}> trace
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffd0150, count: -1
ddb{1}> show registers
rdi                                0
rsi                                0
rbp               0xffff800022d8f5e0
rbx                                0
rdx               0xffff800020ec7d58
rcx                                0
rax                             0x39
r8                0xffffffff821b427f    kprintf+0x16f
r9                               0x1
r10                             0x25
r11               0xc3b8ccd093e9fd17
r12                                0
r13                                0
r14               0xffff800020ec7d58
r15                                0
rip               0xffffffff81da43f1    savectx+0xb1
cs                               0x8
rflags                          0x46
rsp               0xffff800022d8f560
ss                              0x10
savectx+0xb1:   movl    $0,%gs:0x530
ddb{1}> show proc
PROC (syz-executor.1) pid=22718 stat=onproc
    flags process=2<EXEC,8ORPHAN> proc=0
    pri=86, usrpri=86, nice=20
    forw=0xffffffffffffffff, list=0xffff800020e6dad8,0xffff800020ec6778
    process=0xffff800020e81720 user=0xffff800022d8a000, vmspace=0xfffffd807efffb80
    estcpu=36, cpticks=3, pctcpu=0.13
    user=0, sys=1, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 53617  422853  38088      0  2           0                syz-executor.1
 11203  418095  63416      0  2           0                syz-executor.0
 11203  490542  63416      0  3   0x4000080  netio         syz-executor.0
  6115  248604      0      0  3     0x14200  acct          acct
 73132  101849      1      0  3    0x100083  ttyin         getty
 32783  388138      0      0  3     0x14200  bored         sosplice
 63416  120547  53689      0  2       0x482                syz-executor.0
*38088   22718  53689      0  7         0x2                syz-executor.1
 53689  347411   8216      0  3        0x82  thrsleep      syz-fuzzer
 53689   41484   8216      0  2   0x4000482                syz-fuzzer
 53689  209694   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  318604   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689   44527   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  114680   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  191881   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  357726   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  459300   8216      0  3   0x4000082  thrsleep      syz-fuzzer
 53689  414452   8216      0  3   0x4000082  kqread        syz-fuzzer
 53689  508935   8216      0  3   0x4000082  thrsleep      syz-fuzzer
  8216  352945  52935      0  3    0x10008a  pause         ksh
 52935  409674   8224      0  3        0x52  netlock       sshd
  8224  136167      1      0  3        0x80  select        sshd
 65937   74248  82264     74  3    0x100092  bpf           pflogd
 82264  511468      1      0  3        0x80  netio         pflogd
 34824  435082  93298     73  3    0x100090  kqread        syslogd
 93298  157454      1      0  3    0x100082  netio         syslogd
 87130  169966      1     77  3    0x100090  poll          dhclient
 99427  325930      1      0  3        0x80  poll          dhclient
 12611  121824      0      0  3     0x14200  bored         smr
 98661  266814      0      0  2     0x14200                zerothread
 68667  169852      0      0  3     0x14200  aiodoned      aiodoned
 89498  179331      0      0  3     0x14200  syncer        update
 27969  433599      0      0  3     0x14200  cleaner       cleaner
 98008   85047      0      0  3     0x14200  reaper        reaper
 91394  493704      0      0  3     0x14200  pgdaemon      pagedaemon
 28940   43368      0      0  3     0x14200  bored         crynlk
 19137  171577      0      0  3     0x14200  bored         crypto
 14711  454216      0      0  3  0x40014200  acpi0         acpi0
 81402  108942      0      0  3  0x40014200                idle1
 87418    7717      0      0  7     0x14200                softnet
 22687  302915      0      0  3     0x14200  bored         systqmp
   153  120262      0      0  3     0x14200  bored         systq
 90392   95766      0      0  3  0x40014200  bored         softclock
 22620  315486      0      0  3  0x40014200                idle0
     1  472809      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
CPU 1:
exclusive mutex &(curpg)->mdpage.pv_mtx r = 0 (0xfffffd8006ce6078)
#0  witness_lock+0x4c5 sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pmap_enter+0x698 pmap_enter_pv sys/arch/amd64/amd64/pmap.c:1032 [inline]
#3  pmap_enter+0x698 sys/arch/amd64/amd64/pmap.c:2788
#4  uvm_km_kmemalloc_pla+0x355 sys/uvm/uvm_km.c:390
#5  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#6  fork1+0x271 sys/kern/kern_fork.c:365
#7  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#7  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#8  Xsyscall+0x128
Process 38088 (syz-executor.1) thread 0xffff800020ec7d58 (22718)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82672eb0)
#0  witness_lock+0x4c5 sys/kern/subr_witness.c:1164
#1  syscall+0x400 mi_syscall sys/sys/syscall_mi.h:93 [inline]
#1  syscall+0x400 sys/arch/amd64/amd64/trap.c:570
#2  Xsyscall+0x128
exclusive mutex &(curpg)->mdpage.pv_mtx r = 0 (0xfffffd8006ce6078)
#0  witness_lock+0x4c5 sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pmap_enter+0x698 pmap_enter_pv sys/arch/amd64/amd64/pmap.c:1032 [inline]
#3  pmap_enter+0x698 sys/arch/amd64/amd64/pmap.c:2788
#4  uvm_km_kmemalloc_pla+0x355 sys/uvm/uvm_km.c:390
#5  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#6  fork1+0x271 sys/kern/kern_fork.c:365
#7  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#7  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#8  Xsyscall+0x128
Process 87418 (softnet) thread 0xffff800020e18750 (7717)
shared rwlock netlock r = 0 (0xffffffff8248d3b8)
#0  witness_lock+0x4c5 sys/kern/subr_witness.c:1164
#1  if_input_process+0x84 sys/net/if.c:941
#2  ifiq_process+0x80 sys/net/ifq.c:646
#3  taskq_thread+0x9c sys/kern/kern_task.c:369
#4  proc_trampoline+0x1c
shared rwlock softnet r = 0 (0xffff80000002b0e0)
#0  witness_lock+0x4c5 sys/kern/subr_witness.c:1164
#1  taskq_thread+0x8f sys/kern/kern_task.c:368
#2  proc_trampoline+0x1c
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9545   6427K    6874K  78643K     11348        0
            pcb    13      8K       8K  78643K       150        0
         rtable    87      3K       4K  78643K       370        0
         ifaddr    88     15K      16K  78643K       163        0
       counters    43     33K      34K  78643K        61        0
       ioctlops     0      0K       4K  78643K      1490        0
            iov     1     12K      16K  78643K        72        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1223     77K      77K  78643K      1506        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      0K       1K  78643K        64        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1809    196K     290K  78643K     12766        0
      file desc     6     17K      25K  78643K       507        0
          sigio     0      0K       0K  78643K         3        0
           proc    62     63K      83K  78643K       535        0
        subproc    32      2K       2K  78643K        51        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
    ip_moptions     0      0K       0K  78643K        62        0
       in_multi    62      3K       3K  78643K       176        0
    ether_multi     1      0K       0K  78643K        30        0
            mrt     0      0K       0K  78643K        10        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       278        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   116     87K     103K  78643K      2660        0
       UVM aobj    24      2K       3K  78643K        30        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
    ip6_options     0      0K       0K  78643K       140        0
            NDP    16      0K       0K  78643K        34        0
           temp   121   3040K    3115K  78643K     11435        0
         kqueue     3      4K      14K  78643K        42        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        9    0        6     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       45    0       43     1     0     1     1     0     8    0
rtentry    112       74    0       42     2     0     2     2     0     8    0
unpcb      120      336    0      323     1     0     1     1     0     8    0
syncache   264       12    0       12     2     2     0     1     0     8    0
tcpqe       32      125    0      125     2     2     0     1     0     8    0
tcpcb      544      244    0      240     1     0     1     1     0     8    0
inpcb      280     1350    0     1343     2     0     2     2     0     8    1
rttmr       72        3    0        3     2     1     1     1     0     8    1
nd6         48       12    0       10     1     0     1     1     0     8    0
pkpcb       40        4    0        4     2     1     1     1     0     8    1
ppxss      1128       5    0        5     2     1     1     1     0     8    1
pffrag     232        4    0        4     3     2     1     1     0   482    1
pffrnode    88        4    0        4     3     2     1     1     0     8    1
pffrent     40       95    0       95     3     2     1     1     0     8    1
pfosfp      40      846    0      423     5     0     5     5     0     8    0
pfosfpen   112     1428    0      714    21     0    21    21     0     8    0
pfstitem    24       56    0        7     1     0     1     1     0     8    0
pfstkey    112       56    0        7     2     0     2     2     0     8    0
pfstate    328       56    0        7     5     0     5     5     0     8    0
pfrule     1360      21    0       16     2     1     1     2     0     8    0
art_heap8  4096       2    0        0     2     0     2     2     0     8    0
art_heap4  256      350    0      182    12     0    12    12     0     8    1
art_table   32      352    0      182     2     0     2     2     0     8    0
art_node    16       73    0       44     1     0     1     1     0     8    0
sysvmsgpl   40       14    0        7     1     0     1     1     0     8    0
semupl     112        2    0        2     1     1     0     1     0     8    0
semapl     112       54    0       44     1     0     1     1     0     8    0
shmpl      112       28    0        6     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128     2173    0      767    46     0    46    46     0     8    0
ffsino     272     2173    0      767    95     0    95    95     0     8    0
nchpl      144     3028    0     1435    61     0    61    61     0     8    0
uvmvnodes   72     2396    0        0    44     0    44    44     0     8    0
vnodes     208     2396    0        0   127     0   127   127     0     8    0
namei      1024    8395    0     8395     1     0     1     1     0     8    1
percpumem   16       41    0        9     1     0     1     1     0     8    0
vcpupl     1984       6    0        0     1     0     1     1     0     8    0
vmpool     560        9    0        3     1     0     1     1     0     8    0
scsiplug    64        1    0        1     1     1     0     1     0     8    0
scxspl     192     9963    0     9962    10     7     3     7     0     8    2
plimitpl   152       40    0       32     1     0     1     1     0     8    0
sigapl     424      723    0      689     4     0     4     4     0     8    0
futexpl     56     9056    0     9056     1     0     1     1     0     8    1
knotepl    112      107    0       88     1     0     1     1     0     8    0
kqueuepl   144      104    0      102     1     0     1     1     0     8    0
pipelkpl    48      135    0      125     1     0     1     1     0     8    0
pipepl     120      270    0      251     1     0     1     1     0     8    0
fdescpl    496      706    0      689     3     0     3     3     0     8    0
filepl     152     4629    0     4527     5     0     5     5     0     8    1
lockfpl    104      162    0      161     1     0     1     1     0     8    0
lockfspl    48       63    0       62     1     0     1     1     0     8    0
sessionpl  112       21    0       10     1     0     1     1     0     8    0
pgrppl      48       21    0       10     1     0     1     1     0     8    0
ucredpl     96      346    0      337     1     0     1     1     0     8    0
zombiepl   144      689    0      689     1     0     1     1     0     8    1
processpl  984      723    0      689     5     0     5     5     0     8    0
procpl     624     1821    0     1776     4     0     4     4     0     8    0
srpgc       64        6    0        6     2     1     1     1     0     8    1
sosppl     128        6    0        6     2     1     1     1     0     8    1
sockpl     400     1744    0     1722     4     0     4     4     0     8    1
mcl64k     65536      8    0        0     1     0     1     1     0     8    0
mcl12k     12288      5    0        0     1     0     1     1     0     8    0
mcl9k      9216       2    0        0     1     0     1     1     0     8    0
mcl8k      8192       3    0        0     1     0     1     1     0     8    0
mcl4k      4096       7    0        0     1     0     1     1     0     8    0
mcl2k2     2112       1    0        0     1     0     1     1     0     8    0
mcl2k      2048     167    0        0    20     0    20    20     0     8    0
mtagpl      80       20    0        0     1     0     1     1     0     8    0
mbufpl     256      234    0        0    15     0    15    15     0     8    0
bufpl      280     5532    0      178   383     0   383   383     0     8    0
anonpl      16    73304    0    59443    63     1    62    62     0   124    3
amapchunkpl 152    3814    0     3679     9     3     6     8     0   158    0
amappl16   192     3008    0     2223    43     0    43    43     0     8    3
amappl15   184        2    0        0     1     0     1     1     0     8    0
amappl14   176      210    0      208     3     2     1     1     0     8    0
amappl13   168      269    0      267     1     0     1     1     0     8    0
amappl12   160       12    0       10     1     0     1     1     0     8    0
amappl11   152       73    0       54     1     0     1     1     0     8    0
amappl10   144       51    0       44     1     0     1     1     0     8    0
amappl9    136      395    0      391     1     0     1     1     0     8    0
amappl8    128      326    0      308     1     0     1     1     0     8    0
amappl7    120      147    0      135     1     0     1     1     0     8    0
amappl6    112       28    0       24     1     0     1     1     0     8    0
amappl5    104      610    0      592     1     0     1     1     0     8    0
amappl4     96      752    0      722     1     0     1     1     0     8    0
amappl3     88      327    0      321     1     0     1     1     0     8    0
amappl2     80     4671    0     4602     3     1     2     3     0     8    0
amappl1     72    25196    0    24755    26    15    11    20     0     8    0
amappl      80     2090    0     2042     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        6     1     0     1     1     0     8    0
uaddrrnd    24      715    0      692     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      715    0      692     1     0     1     1     0     8    0
vmmpekpl   168     9331    0     9293     2     0     2     2     0     8    0
vmmpepl    168    92599    0    90601   114    22    92   107     0   357    3
vmsppl     368      714    0      692     3     0     3     3     0     8    0
pdppl      4096    1438    0     1390     7     0     7     7     0     8    0
pvpl        32   240476    0   223436   160     2   158   158     0   265   14
pmappl     232      714    0      692     3     1     2     2     0     8    0
extentpl    40       46    0       29     1     0     1     1     0     8    0
phpool     112      174    0        3     5     0     5     5     0     8    0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/04/06 18:04 openbsd e0f5a5efbe63 34833561 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.