syzbot


panic: WApRoNolI_NGc:a chSePL_ itNeOTm _mLOagWEiRcE_Dc hOecN k:SY SmCbuALfLp l 2 c-pu94 59fr7e1e59 8li EsXt ITm o0d iafi

Status: closed as dup on 2020/01/26 10:00
Reported-by: syzbot+92cacabe000768032a3d@syzkaller.appspotmail.com
First crash: 1762d, last: 1762d
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: WApRoNolI_NGc:a chSePL_ itNeOTm _mLOagWEiRcE_Dc hOecN k:SY SmCbuALfLp l 2 c-pu94 59fr7e1e59 8li EsXt ITm o0d iafi
edStopped at      savectx+0xb1:   movl    $0,%gs:0x530
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*372403  49318      0         0x2          0    0  syz-executor.0
 439627  26360      0     0x14000      0x200    1  softnet
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffcc490, 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{0}> 
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806909c700+16 0x0!=0xe56fcb51226879cb
ddb{0}> trace
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffcc490, count: -1
ddb{0}> show registers
rdi                                0
rsi                                0
rbp               0xffff800020b7d840
rbx                                0
rdx               0xffff800020a7dd48
rcx                                0
rax                             0x3a
r8                0xffffffff8167311f    kprintf+0x16f
r9                               0x1
r10                             0x25
r11               0xfda88a10f5424066
r12                                0
r13                                0
r14               0xffff800020a7dd48
r15                                0
rip               0xffffffff8167a3f1    savectx+0xb1
cs                               0x8
rflags                          0x46
rsp               0xffff800020b7d7c0
ss                              0x10
savectx+0xb1:   movl    $0,%gs:0x530
ddb{0}> show proc
PROC (syz-executor.0) pid=372403 stat=onproc
    flags process=2<EXEC> proc=0
    pri=74, usrpri=74, nice=20
    forw=0xffffffffffffffff, list=0xffff800020a7c008,0xffff800020ac3d68
    process=0xffff800020a903d0 user=0xffff800020b78000, vmspace=0xfffffd807efffa10
    estcpu=36, cpticks=1, pctcpu=0.6
    user=0, sys=1, intr=0
ddb{0}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 42551  469164  49318      0  2           0                syz-executor.0
  5930  291234  22419      0  2           0                syz-executor.1
 47644  409398      0      0  3     0x14200  bored         sosplice
 22419  262609  47424      0  3        0x82  nanosleep     syz-executor.1
*49318  372403  47424      0  7         0x2                syz-executor.0
 47424  139286  33857      0  3        0x82  nanosleep     syz-fuzzer
 47424  199850  33857      0  3   0x4000082  nanosleep     syz-fuzzer
 47424  305863  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424  328945  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424   91801  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424   38666  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424  500755  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424  322983  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 47424  410978  33857      0  3   0x4000082  kqread        syz-fuzzer
 47424  241141  33857      0  3   0x4000082  thrsleep      syz-fuzzer
 33857  378033  63848      0  3    0x10008a  pause         ksh
 63848  288110  27028      0  3        0x92  select        sshd
 94203   14101      1      0  3    0x100083  ttyin         getty
 27028   45159      1      0  3        0x80  select        sshd
 33827  428183  76071     74  3    0x100092  bpf           pflogd
 76071  350486      1      0  3        0x80  netio         pflogd
 98980   24589  23369     73  3    0x100090  kqread        syslogd
 23369  198865      1      0  3    0x100082  netio         syslogd
 76997  478498      1     77  3    0x100090  poll          dhclient
 48074  416369      1      0  3        0x80  poll          dhclient
 93549  504394      0      0  2     0x14200                zerothread
 89212  479098      0      0  3     0x14200  aiodoned      aiodoned
 36906  453539      0      0  3     0x14200  syncer        update
 39744  335920      0      0  3     0x14200  cleaner       cleaner
 77082  483634      0      0  3     0x14200  reaper        reaper
 56290  387003      0      0  3     0x14200  pgdaemon      pagedaemon
 67904  417569      0      0  3     0x14200  bored         crynlk
 34932   45234      0      0  3     0x14200  bored         crypto
 18720  310249      0      0  3  0x40014200  acpi0         acpi0
 30704  259132      0      0  3  0x40014200                idle1
 26360  439627      0      0  7     0x14200                softnet
 52622   85548      0      0  3     0x14200  bored         systqmp
 99227   33202      0      0  3     0x14200  bored         systq
 23146  111371      0      0  3  0x40014200  bored         softclock
 85549   59299      0      0  3  0x40014200                idle0
 89712  165132      0      0  3     0x14200  bored         smr
     1  144328      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{0}> show all locks
CPU 0:
exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff826409e0)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  uvm_pmr_getpages+0xd2c sys/uvm/uvm_pmemrange.c:1170
#4  uvm_pglistalloc+0x362 sys/uvm/uvm_page.c:790
#5  uvm_km_kmemalloc_pla+0x238 sys/uvm/uvm_km.c:366
#6  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#7  fork1+0x295 sys/kern/kern_fork.c:367
#8  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#8  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#9  Xsyscall+0x128
Process 49318 (syz-executor.0) thread 0xffff800020a7dd48 (372403)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8263e0d8)
#0  witness_lock+0x52e 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 &uvm.fpageqlock r = 0 (0xffffffff826409e0)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  uvm_pmr_getpages+0xd2c sys/uvm/uvm_pmemrange.c:1170
#4  uvm_pglistalloc+0x362 sys/uvm/uvm_page.c:790
#5  uvm_km_kmemalloc_pla+0x238 sys/uvm/uvm_km.c:366
#6  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#7  fork1+0x295 sys/kern/kern_fork.c:367
#8  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#8  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#9  Xsyscall+0x128
Process 26360 (softnet) thread 0xffff800020a28270 (439627)
shared rwlock netlock r = 0 (0xffffffff824dac08)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  if_input_process+0x84 sys/net/if.c:941
#2  ifiq_process+0x80 sys/net/ifq.c:607
#3  taskq_thread+0x9c sys/kern/kern_task.c:369
#4  proc_trampoline+0x1c
shared rwlock softnet r = 0 (0xffff80000002b0e0)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  taskq_thread+0x8f sys/kern/kern_task.c:368
#2  proc_trampoline+0x1c
ddb{0}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9493   6405K    6791K  78643K     10755        0
            pcb    13      8K       8K  78643K        39        0
         rtable   105      3K       3K  78643K       247        0
         ifaddr    57     12K      13K  78643K        80        0
       counters    43     33K      34K  78643K        49        0
       ioctlops     0      0K       4K  78643K      1474        0
            iov     0      0K      12K  78643K         7        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1217     76K      77K  78643K      1271        0
      UFS quota     1     32K      32K  78643K         1        0
      UFS mount     5     36K      36K  78643K         5        0
            shm     2      1K       5K  78643K         3        0
         VM map     2      1K       1K  78643K         2        0
            sem    12      0K       0K  78643K        16        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1809    196K     290K  78643K     12766        0
      file desc     6     17K      25K  78643K       107        0
          sigio     0      0K       0K  78643K         1        0
           proc    60     63K      95K  78643K       447        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        86        0
       in_multi    46      2K       2K  78643K        51        0
    ether_multi     1      0K       0K  78643K         3        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    37    175K     175K  78643K        37        0
           exec     0      0K       1K  78643K       209        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   117     38K      42K  78643K      1317        0
       UVM aobj    10      2K       2K  78643K        10        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
    ip6_options     0      0K       0K  78643K        16        0
            NDP     8      0K       0K  78643K        15        0
           temp    79   3009K    3073K  78643K      2319        0
         kqueue     3      4K      20K  78643K        15        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        8    0        2     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       27    0       25     1     0     1     1     0     8    0
rtentry    112       51    0        7     2     0     2     2     0     8    0
unpcb      120       76    0       66     1     0     1     1     0     8    0
syncache   264        5    0        5     2     1     1     1     0     8    1
sackhl      24        1    0        1     1     0     1     1     0     8    1
tcpqe       32       25    0       25     2     1     1     1     0     8    1
tcpcb      544      155    0      151     2     0     2     2     0     8    1
inpcb      280      253    0      246     3     1     2     3     0     8    1
nd6         48        4    0        0     1     0     1     1     0     8    0
pkpcb       40        4    0        4     1     1     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
pfstitem    24       29    0        2     1     0     1     1     0     8    0
pfstkey    112       29    0        2     1     0     1     1     0     8    0
pfstate    328       29    0        0     3     0     3     3     0     8    0
pfrule     1360      21    0       16     2     1     1     2     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      226    0        9    14     0    14    14     0     8    0
art_table   32      227    0        9     2     0     2     2     0     8    0
art_node    16       50    0       10     1     0     1     1     0     8    0
sysvmsgpl   40        2    0        0     1     0     1     1     0     8    0
semupl     112        3    0        3     1     0     1     1     0     8    1
semapl     112       14    0        4     1     0     1     1     0     8    0
shmpl      112        8    0        0     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128     1526    0      119    46     0    46    46     0     8    0
ffsino     272     1526    0      119    95     0    95    95     0     8    0
nchpl      144     1890    0      273    61     0    61    61     0     8    0
uvmvnodes   72     1607    0        0    30     0    30    30     0     8    0
vnodes     208     1607    0        0    85     0    85    85     0     8    0
namei      1024    4995    0     4995     1     0     1     1     0     8    1
percpumem   16       35    0        3     1     0     1     1     0     8    0
vcpupl     1984       1    0        0     1     0     1     1     0     8    0
vmpool     560        1    0        0     1     0     1     1     0     8    0
scxspl     192     5619    0     5619     8     4     4     7     0     8    4
plimitpl   152       21    0       13     1     0     1     1     0     8    0
sigapl     432      306    0      290     3     1     2     3     0     8    0
futexpl     56     1830    0     1830     1     0     1     1     0     8    1
knotepl    112       68    0       49     1     0     1     1     0     8    0
kqueuepl   104       36    0       34     1     0     1     1     0     8    0
pipelkpl    48       96    0       86     1     0     1     1     0     8    0
pipepl     120      192    0      173     1     0     1     1     0     8    0
fdescpl    496      307    0      290     3     0     3     3     0     8    0
filepl     152     1936    0     1836     6     0     6     6     0     8    2
lockfpl    104       35    0       34     1     0     1     1     0     8    0
lockfspl    48       15    0       14     1     0     1     1     0     8    0
sessionpl  112       18    0        7     1     0     1     1     0     8    0
pgrppl      48       22    0       11     1     0     1     1     0     8    0
ucredpl     96      112    0      103     1     0     1     1     0     8    0
zombiepl   144      290    0      290     1     0     1     1     0     8    1
processpl  960      323    0      290     5     0     5     5     0     8    0
procpl     624      521    0      479     4     0     4     4     0     8    0
sockpl     400      360    0      341     5     0     5     5     0     8    3
mcl64k     65536      6    0        0     1     0     1     1     0     8    0
mcl12k     12288      1    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       3    0        0     1     0     1     1     0     8    0
mcl2k      2048     172    0        0    21     0    21    21     0     8    0
mtagpl      80        7    0        0     1     0     1     1     0     8    0
mbufpl     256      187    0        0    11     0    11    11     0     8    0
bufpl      280     5366    0      191   370     0   370   370     0     8    0
anonpl      16    52921    0    36794    82     1    81    81     0   125   14
amapchunkpl 152    2238    0     2095    20     5    15    20     0   158    7
amappl16   192     1735    0      866    55     2    53    55     0     8    8
amappl15   184       66    0       62     1     0     1     1     0     8    0
amappl14   176       28    0       26     1     0     1     1     0     8    0
amappl12   160       52    0       49     2     1     1     1     0     8    0
amappl11   152       59    0       43     1     0     1     1     0     8    0
amappl10   144       52    0       44     1     0     1     1     0     8    0
amappl9    136      601    0      597     1     0     1     1     0     8    0
amappl8    128      117    0       98     1     0     1     1     0     8    0
amappl7    120      134    0      122     1     0     1     1     0     8    0
amappl6    112       60    0       52     1     0     1     1     0     8    0
amappl5    104      176    0      161     1     0     1     1     0     8    0
amappl4     96      557    0      524     2     1     1     2     0     8    0
amappl3     88      116    0      109     1     0     1     1     0     8    0
amappl2     80     1493    0     1425     3     1     2     3     0     8    0
amappl1     72    16794    0    16356    25    15    10    20     0     8    0
amappl      80      788    0      742     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        9    0        0     1     0     1     1     0     8    0
uaddrrnd    24      308    0      290     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      308    0      290     1     0     1     1     0     8    0
vmmpekpl   168     6466    0     6431     2     0     2     2     0     8    0
vmmpepl    168    45454    0    43365   122    10   112   117     0   357   20
vmsppl     368      307    0      290     2     0     2     2     0     8    0
pdppl      4096     623    0      581     6     0     6     6     0     8    0
pvpl        32   161555    0   142295   192     0   192   192     0   265   35
pmappl     232      307    0      290     2     0     2     2     0     8    1
extentpl    40       46    0       29     1     0     1     1     0     8    0
phpool     112      172    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
2020/01/25 13:52 openbsd 61e8dc34fbac 2e95ab33 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.