syzbot


panicW: ARpNoIoNlG_:c aScPhLe _NiOteT mL_OmWaEgRiEc_D cOhNe cSkY: SCmAbLuLf pl2 2c1p4u 23f6r0e46e0 lEisXItT m0o ad

Status: closed as dup on 2020/05/27 07:26
Reported-by: syzbot+b172bd0be6cd543047bc@syzkaller.appspotmail.com
First crash: 1640d, last: 1640d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
pool: cpu free list modified: mbufpl syz 15863 1570d 1856d

Sample crash report:
panicW: ARpNoIoNlG_:c aScPhLe _NiOteT mL_OmWaEgRiEc_D cOhNe cSkY: SCmAbLuLf pl2  2c1p4u 23f6r0e46e0  lEisXItT  m0o ad
i
fStopped at      savectx+0xb1:   movl    $0,%gs:0x530
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 63287  72384      0         0x2          0    1  syz-executor.1
 339181  54047      0        0x12          0    0  sshd
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffe3eb0, 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 0xfffffd8068e3d900+16 0x0!=0x294b71bdefa9d10b
ddb{1}> trace
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffe3eb0, count: -1
ddb{1}> show registers
rdi                                0
rsi                                0
rbp               0xffff800021f832a0
rbx                                0
rdx                             0x8b
rcx                              0x2
rax                             0x3a
r8                0xffffffff8210a11f    kprintf+0x16f
r9                               0x1
r10                              0x2
r11               0x8e3d8e4369933997
r12                                0
r13                                0
r14               0xffff800020ecf128
r15                                0
rip               0xffffffff8115d3f1    savectx+0xb1
cs                               0x8
rflags                          0x46
rsp               0xffff800021f83220
ss                              0x10
savectx+0xb1:   movl    $0,%gs:0x530
ddb{1}> show proc
PROC (syz-executor.1) pid=63287 stat=onproc
    flags process=2<EXEC,8ORPHAN> proc=0
    pri=16, usrpri=54, nice=20
    forw=0xffffffffffffffff, list=0xffff800020ece4f8,0xffff800020ece028
    process=0xffff800020ed8bb0 user=0xffff800021f7e000, vmspace=0xfffffd807efff5c0
    estcpu=4, cpticks=1, pctcpu=0.3
    user=0, sys=1, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 64891  461231  72384      0  2           0                syz-executor.1
*72384   63287  18635      0  7         0x2                syz-executor.1
 43727   94719      0      0  3     0x14200  acct          acct
 56888  434341      0      0  3     0x14200  bored         sosplice
 16727  100802  18635      0  3        0x82  piperd        syz-executor.0
 18635   24963  18502      0  3        0x82  thrsleep      syz-fuzzer
 18635   21350  18502      0  2   0x4000482                syz-fuzzer
 18635  399744  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18635  427369  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18635  229518  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18635  380333  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18635  150102  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18635  399139  18502      0  2   0x4000002                syz-fuzzer
 18635    5757  18502      0  2   0x4000002                syz-fuzzer
 18635  307095  18502      0  3   0x4000082  thrsleep      syz-fuzzer
 18502  145376  54047      0  3    0x10008a  pause         ksh
 54047  339181  35917      0  7        0x12                sshd
 95172  284131      1      0  3    0x100083  ttyin         getty
 35917  494958      1      0  3        0x80  select        sshd
 96642  482120  53704     74  3    0x100092  bpf           pflogd
 53704  291621      1      0  3        0x80  netio         pflogd
 33663  426200  57260     73  3    0x100090  kqread        syslogd
 57260    7559      1      0  3    0x100082  netio         syslogd
 28511  519518      1     77  3    0x100090  poll          dhclient
 65936  516021      1      0  3        0x80  poll          dhclient
 11676  332729      0      0  3     0x14200  bored         smr
 93434  426086      0      0  2     0x14200                zerothread
 99432  289126      0      0  3     0x14200  aiodoned      aiodoned
 36422  300508      0      0  3     0x14200  syncer        update
 53506  113263      0      0  3     0x14200  cleaner       cleaner
 95510  488207      0      0  3     0x14200  reaper        reaper
 11337  103437      0      0  3     0x14200  pgdaemon      pagedaemon
 61506  431770      0      0  3     0x14200  bored         crynlk
 79062  285566      0      0  3     0x14200  bored         crypto
 84696  117005      0      0  3  0x40014200  acpi0         acpi0
 85980   18767      0      0  3  0x40014200                idle1
 82492   30185      0      0  3     0x14200  bored         softnet
 84475  175683      0      0  3     0x14200  bored         systqmp
 61305  412363      0      0  3     0x14200  bored         systq
  1718  396561      0      0  3  0x40014200  bored         softclock
  4793  476608      0      0  3  0x40014200                idle0
     1  465712      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
CPU 1:
exclusive mutex vmmpekpl r = 0 (0xffffffff8264f970)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pool_put+0x64 sys/kern/subr_pool.c:792
#4  uvm_unmap_detach+0x231 sys/uvm/uvm_map.c:1581
#5  uvm_map+0xe0c sys/uvm/uvm_map.c:1420
#6  uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:335
#7  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#8  fork1+0x271 sys/kern/kern_fork.c:365
#9  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#9  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#10 Xsyscall+0x128
Process 72384 (syz-executor.1) thread 0xffff800020ecf128 (63287)
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8268a470)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 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 vmmpekpl r = 0 (0xffffffff8264f970)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1  mtx_enter_try+0x102
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pool_put+0x64 sys/kern/subr_pool.c:792
#4  uvm_unmap_detach+0x231 sys/uvm/uvm_map.c:1581
#5  uvm_map+0xe0c sys/uvm/uvm_map.c:1420
#6  uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:335
#7  uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274
#8  fork1+0x271 sys/kern/kern_fork.c:365
#9  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#9  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#10 Xsyscall+0x128
Process 54047 (sshd) thread 0xffff800020ed1390 (339181)
exclusive rwlock netlock r = 0 (0xffffffff824b44a8)
#0  witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4c7 sys/kern/subr_witness.c:1164
#1  solock+0x5a sys/kern/uipc_socket2.c:282
#2  sosend+0x559 sys/kern/uipc_socket.c:537
#3  dofilewritev+0x1b6 sys/kern/sys_generic.c:365
#4  sys_write+0x83 sys/kern/sys_generic.c:285
#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
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9507   6426K    6932K  78643K     10866        0
            pcb    13      8K       8K  78643K        57        0
         rtable   105      3K       3K  78643K       302        0
         ifaddr    63     13K      13K  78643K        85        0
       counters    43     33K      34K  78643K        47        0
       ioctlops     0      0K       4K  78643K      1472        0
            iov     0      0K      12K  78643K        10        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1219     77K      77K  78643K      1320        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      1K       1K  78643K         2        0
            sem    12      0K       0K  78643K        24        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1824    197K     290K  78643K     13058        0
      file desc     5     13K      25K  78643K       197        0
          sigio     0      0K       0K  78643K         2        0
           proc    61     63K      95K  78643K       483        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        14        0
       in_multi    40      2K       2K  78643K        98        0
    ether_multi     1      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       238        0
     pfkey data     0      0K       0K  78643K         2        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   120     38K      39K  78643K      1569        0
       UVM aobj     6      2K       2K  78643K         6        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
    ip6_options     0      0K       0K  78643K        40        0
            NDP    10      0K       0K  78643K        22        0
           temp    88   3033K    3101K  78643K      4351        0
         kqueue     3      4K      12K  78643K        20        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        8    0        2     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       25    0       23     1     0     1     1     0     8    0
rtentry    112       72    0       28     2     0     2     2     0     8    0
unpcb      120      165    0      155     1     0     1     1     0     8    0
syncache   264        5    0        5     2     2     0     1     0     8    0
tcpqe       32      769    0      769     1     1     0     1     0     8    0
tcpcb      544       75    0       71     1     0     1     1     0     8    0
inpcb      280      268    0      261     2     1     1     2     0     8    0
nd6         48       13    0        7     1     0     1     1     0     8    0
pkpcb       40        2    0        2     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       25    0        4     1     0     1     1     0     8    0
pfstkey    112       25    0        4     1     0     1     1     0     8    0
pfstate    328       25    0        4     2     0     2     2     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      328    0      140    14     2    12    13     0     8    0
art_table   32      329    0      140     2     0     2     2     0     8    0
art_node    16       71    0       31     1     0     1     1     0     8    0
sysvmsgpl   40        5    0        4     1     0     1     1     0     8    0
semapl     112       22    0       12     1     0     1     1     0     8    0
shmpl      112        4    0        0     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1642    0      236    89     0    89    89     0     8    0
ffsino     272     1642    0      236    96     1    95    95     0     8    0
nchpl      144     2115    0      521    60     0    60    60     0     8    0
uvmvnodes   72     1761    0        0    33     0    33    33     0     8    0
vnodes     208     1761    0        0    93     0    93    93     0     8    0
namei      1024    5744    0     5744     2     1     1     1     0     8    1
percpumem   16       34    0        2     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
scsiplug    64        2    0        2     1     0     1     1     0     8    1
scxspl     192     6942    0     6942     8     7     1     7     0     8    1
plimitpl   152       28    0       20     1     0     1     1     0     8    0
sigapl     424      411    0      378     4     0     4     4     0     8    0
futexpl     56     2308    0     2308     1     0     1     1     0     8    1
knotepl    112       92    0       73     1     0     1     1     0     8    0
kqueuepl   144       38    0       36     1     0     1     1     0     8    0
pipelkpl    48      120    0      110     1     0     1     1     0     8    0
pipepl     120      240    0      221     1     0     1     1     0     8    0
fdescpl    496      394    0      378     3     0     3     3     0     8    0
filepl     152     2309    0     2209     6     1     5     5     0     8    1
lockfpl    104       38    0       37     1     0     1     1     0     8    0
lockfspl    48       17    0       16     1     0     1     1     0     8    0
sessionpl  112       19    0        8     1     0     1     1     0     8    0
pgrppl      48       21    0       10     1     0     1     1     0     8    0
ucredpl     96      154    0      144     1     0     1     1     0     8    0
zombiepl   144      378    0      378     2     1     1     1     0     8    1
processpl  984      411    0      378     6     1     5     5     0     8    0
procpl     624      757    0      715     4     0     4     4     0     8    0
sosppl     128        5    0        5     2     1     1     1     0     8    1
sockpl     400      460    0      441     5     2     3     4     0     8    1
mcl64k     65536      4    0        0     1     0     1     1     0     8    0
mcl12k     12288      2    0        0     1     0     1     1     0     8    0
mcl9k      9216       1    0        0     1     0     1     1     0     8    0
mcl4k      4096       5    0        0     1     0     1     1     0     8    0
mcl2k2     2112       1    0        0     1     0     1     1     0     8    0
mcl2k      2048     176    0        0    21     0    21    21     0     8    0
mtagpl      80       24    0        0     1     0     1     1     0     8    0
mbufpl     256      503    0        0    31     0    31    31     0     8    0
bufpl      280     4992    0      135   347     0   347   347     0     8    0
anonpl      16    55042    0    43598    75     1    74    74     0   124   16
amapchunkpl 152    2156    0     2016     9     2     7     8     0   158    0
amappl16   192     1848    0     1094    50     4    46    50     0     8    7
amappl15   184        9    0        7     1     0     1     1     0     8    0
amappl14   176       97    0       89     1     0     1     1     0     8    0
amappl13   168       47    0       42     1     0     1     1     0     8    0
amappl12   160       78    0       73     2     1     1     1     0     8    0
amappl11   152       55    0       40     1     0     1     1     0     8    0
amappl10   144       18    0       11     1     0     1     1     0     8    0
amappl9    136      357    0      355     1     0     1     1     0     8    0
amappl8    128      443    0      411     2     0     2     2     0     8    0
amappl7    120      127    0      114     1     0     1     1     0     8    0
amappl6    112       28    0       23     1     0     1     1     0     8    0
amappl5    104      487    0      471     1     0     1     1     0     8    0
amappl4     96      507    0      476     1     0     1     1     0     8    0
amappl3     88      115    0      108     1     0     1     1     0     8    0
amappl2     80     2187    0     2126     2     0     2     2     0     8    0
amappl1     72    18785    0    18358    23    13    10    18     0     8    0
amappl      80     1028    0      982     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        5    0        0     1     0     1     1     0     8    0
uaddrrnd    24      395    0      378     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      395    0      378     1     0     1     1     0     8    0
vmmpekpl   168     7070    0     7039     2     0     2     2     0     8    0
vmmpepl    168    55626    0    53746   126    13   113   113     0   357   28
vmsppl     368      394    0      378     2     0     2     2     0     8    0
pdppl      4096     798    0      757     6     0     6     6     0     8    0
pvpl        32   178238    0   163703   181     4   177   177     0   265   34
pmappl     232      394    0      378     3     1     2     2     0     8    1
extentpl    40       53    0       36     1     0     1     1     0     8    0
phpool     112      281    0        9     8     0     8     8     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x1a:        addq    $0x8,%rsp
x86_ipi_db(ffffffff824b2ff0) 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
x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639
comcnputc(800,69) at comcnputc+0xb8 sys/dev/ic/com.c:1250
cnputc(69) at cnputc+0x4c sys/dev/cons.c:239
kputchar(69,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343
kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700
panic(ffffffff821fb214) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline]
panic(ffffffff821fb214) at panic+0xf3 sys/kern/subr_prf.c:197
pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline]
pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884
pool_get(ffffffff82667020,2) at pool_get+0x91 sys/kern/subr_pool.c:572
m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline]
m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667
tcp_output(ffff800000a0b100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673
tcp_usrreq(fffffd806eb407d8,9,fffffd8068e3c600,0,0,ffff800020ed1390) at tcp_usrreq+0xa55
end trace frame: 0xffff800020ed7480, count: 0
ddb{0}> trace
x86_ipi_db(ffffffff824b2ff0) 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
x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639
comcnputc(800,69) at comcnputc+0xb8 sys/dev/ic/com.c:1250
cnputc(69) at cnputc+0x4c sys/dev/cons.c:239
kputchar(69,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343
kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700
panic(ffffffff821fb214) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline]
panic(ffffffff821fb214) at panic+0xf3 sys/kern/subr_prf.c:197
pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline]
pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884
pool_get(ffffffff82667020,2) at pool_get+0x91 sys/kern/subr_pool.c:572
m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline]
m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667
tcp_output(ffff800000a0b100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673
tcp_usrreq(fffffd806eb407d8,9,fffffd8068e3c600,0,0,ffff800020ed1390) at tcp_usrreq+0xa55
sosend(fffffd806eb407d8,0,ffff800020ed7548,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549
dofilewritev(ffff800020ed1390,4,ffff800020ed7548,0,ffff800020ed7630) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365
sys_write(ffff800020ed1390,ffff800020ed75e0,ffff800020ed7630) at sys_write+0x83 sys/kern/sys_generic.c:285
syscall(ffff800020ed76b0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800020ed76b0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffd9330, count: -19
ddb{0}> machine ddbcpu 1
Stopped at      savectx+0xb1:   movl    $0,%gs:0x530
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffe3eb0, count: 14
ddb{1}> trace
savectx() at savectx+0xb1
end of kernel
end trace frame: 0x7f7ffffe3eb0, count: -1

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/26 13:16 openbsd 4e2f099e1acf 8ca3b7d2 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.