syzbot


panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr ADDR+16 ADDR!=ADDR

Status: closed as dup on 2019/10/22 10:46
Reported-by: syzbot+a2ac004ee1d48c0b510e@syzkaller.appspotmail.com
First crash: 1891d, last: 1857d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr ADDR+16 0x0!=ADDR (2) syz 40 1858d 1891d

Sample crash report:
login: panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806d499100+16 0x656fd022b81e6500!=0x656fd022b81e658c
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*425262  20121      0           0  0x4000000    1K syz-executor.1
 311862  40267      0         0x2  0x4000000    0  syz-fuzzer
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
pool_cache_get(ffffffff8263f268) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline]
pool_cache_get(ffffffff8263f268) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892
pool_get() at pool_get+0x91 sys/kern/subr_pool.c:572
m_gethdr(2,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283
rtm_msg1(2,ffff800021b7b030) at rtm_msg1+0x6e sys/net/rtsock.c:1511
rtm_send(fffffd806f49cc40,2,0,0) at rtm_send+0x120 rtm_miss sys/net/rtsock.c:1656 [inline]
rtm_send(fffffd806f49cc40,2,0,0) at rtm_send+0x120 sys/net/rtsock.c:1634
rtdeletemsg(fffffd806f49cc40,ffff800000a99000,0) at rtdeletemsg+0x199 sys/net/route.c:682
rt_ifa_purge(ffff800000a47000) at rt_ifa_purge+0x104 sys/net/route.c:1324
in6_unlink_ifa(ffff800000a47000,ffff800000a99000) at in6_unlink_ifa+0x580 sys/netinet6/in6.c:939
in6_purgeaddr(ffff800000a47000) at in6_purgeaddr+0x1d7 sys/netinet6/in6.c:920
ifnewlladdr(ffff800000a99000) at ifnewlladdr+0x108 sys/net/if.c:3039
ifioctl(fffffd806f6cb480,8020691f,ffff800021b7b4f0,ffff800020ab1160) at ifioctl+0x17b0 sys/net/if.c:2144
sys_ioctl(ffff800020ab1160,ffff800021b7b608,ffff800021b7b650) at sys_ioctl+0x5b9
end trace frame: 0xffff800021b7b6c0, count: 0
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 0xfffffd806d499100+16 0x656fd022b81e6500!=0x656fd022b81e658c
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
pool_cache_get(ffffffff8263f268) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline]
pool_cache_get(ffffffff8263f268) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892
pool_get() at pool_get+0x91 sys/kern/subr_pool.c:572
m_gethdr(2,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283
rtm_msg1(2,ffff800021b7b030) at rtm_msg1+0x6e sys/net/rtsock.c:1511
rtm_send(fffffd806f49cc40,2,0,0) at rtm_send+0x120 rtm_miss sys/net/rtsock.c:1656 [inline]
rtm_send(fffffd806f49cc40,2,0,0) at rtm_send+0x120 sys/net/rtsock.c:1634
rtdeletemsg(fffffd806f49cc40,ffff800000a99000,0) at rtdeletemsg+0x199 sys/net/route.c:682
rt_ifa_purge(ffff800000a47000) at rt_ifa_purge+0x104 sys/net/route.c:1324
in6_unlink_ifa(ffff800000a47000,ffff800000a99000) at in6_unlink_ifa+0x580 sys/netinet6/in6.c:939
in6_purgeaddr(ffff800000a47000) at in6_purgeaddr+0x1d7 sys/netinet6/in6.c:920
ifnewlladdr(ffff800000a99000) at ifnewlladdr+0x108 sys/net/if.c:3039
ifioctl(fffffd806f6cb480,8020691f,ffff800021b7b4f0,ffff800020ab1160) at ifioctl+0x17b0 sys/net/if.c:2144
sys_ioctl(ffff800020ab1160,ffff800021b7b608,ffff800021b7b650) at sys_ioctl+0x5b9
syscall(ffff800021b7b6d0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800021b7b6d0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff36,0,3,1ec309de010) at Xsyscall+0x128
end of kernel
end trace frame: 0x1ee599fc4f0, count: -16
ddb{1}> show registers
rdi               0xffffffff82030057    db_enter+0x17
rsi                          0x268f3    acpi_pdirpa+0x1275b
rbp               0xffff800021b7ad50
rbx               0xffff800021b7ae00
rdx                          0x268f4    acpi_pdirpa+0x1275c
rcx               0xffff800022b84000
rax               0xffff800022b84000
r8                0xffffffff81f4bdef    kprintf+0x16f
r9                               0x1
r10                             0x25
r11               0xe734126250baf2f2
r12                     0x3000000008
r13               0xffff800021b7ad60
r14                            0x100
r15                              0x1
rip               0xffffffff82030058    db_enter+0x18
cs                               0x8
rflags                         0x246
rsp               0xffff800021b7ad40
ss                              0x10
db_enter+0x18:  addq    $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor.1) pid=425262 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=86, usrpri=86, nice=20
    forw=0xffffffffffffffff, list=0xffff800020ab0ee8,0xffffffff82677a30
    process=0xffff800020adca80 user=0xffff800021b76000, vmspace=0xfffffd807f00a8a0
    estcpu=36, cpticks=2, pctcpu=0.0
    user=0, sys=2, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 20121  273800  44204      0  2           0                syz-executor.1
*20121  425262  44204      0  7   0x4000000                syz-executor.1
 21700  241063      1      0  3    0x100083  ttyin         getty
 22219  108459      0      0  3     0x14200  bored         sosplice
 44204  155155  40267      0  3        0x82  nanosleep     syz-executor.1
 99808  235364  40267      0  3         0x2  biowait       syz-executor.0
 40267   30257  78986      0  3        0x82  thrsleep      syz-fuzzer
 40267  159087  78986      0  3   0x4000082  nanosleep     syz-fuzzer
 40267  182494  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 40267  142058  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 40267    7276  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 40267   49371  78986      0  3   0x4000082  kqread        syz-fuzzer
 40267  180640  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 40267  155157  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 40267  311862  78986      0  7   0x4000002                syz-fuzzer
 40267  192736  78986      0  3   0x4000082  thrsleep      syz-fuzzer
 78986  268596  66283      0  3    0x10008a  pause         ksh
 66283  421715  75273      0  3        0x92  select        sshd
 75273   79200      1      0  3        0x80  select        sshd
 37481  402799  46875     74  3    0x100092  bpf           pflogd
 46875  177412      1      0  3        0x80  netio         pflogd
 40916  114889  64039     73  3    0x100090  kqread        syslogd
 64039  264956      1      0  3    0x100082  netio         syslogd
  7847  428442      1     77  3    0x100090  poll          dhclient
 46692  389466      1      0  3        0x80  poll          dhclient
 58931  448986      0      0  2     0x14200                zerothread
 73144  471706      0      0  3     0x14200  aiodoned      aiodoned
 47057  121454      0      0  3     0x14200  syncer        update
 67418  262835      0      0  3     0x14200  cleaner       cleaner
 24188  500000      0      0  3     0x14200  reaper        reaper
 61965  303672      0      0  3     0x14200  pgdaemon      pagedaemon
   141  191758      0      0  3     0x14200  bored         crynlk
 47490  441922      0      0  3     0x14200  bored         crypto
 28792  101434      0      0  3  0x40014200  acpi0         acpi0
 75533  369362      0      0  3  0x40014200                idle1
 59639   88207      0      0  3     0x14200  bored         softnet
 95822   63627      0      0  2     0x14200                systqmp
 46877  198480      0      0  3     0x14200  bored         systq
   786  175929      0      0  3  0x40014200  bored         softclock
 38216  199448      0      0  3  0x40014200                idle0
 14729  483505      0      0  3     0x14200  bored         smr
     1  299480      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 20121 (syz-executor.1) thread 0xffff800020ab1160 (425262)
exclusive rwlock netlock r = 0 (0xffffffff8248fc78)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  ifioctl+0xdcf sys/net/if.c:2127
#2  sys_ioctl+0x5b9
#3  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#3  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
#4  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82649290)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  syscall+0x400 mi_syscall sys/sys/syscall_mi.h:83 [inline]
#1  syscall+0x400 sys/arch/amd64/amd64/trap.c:555
#2  Xsyscall+0x128
Process 99808 (syz-executor.0) thread 0xffff800020ab0c70 (235364)
exclusive rrwlock inode r = 0 (0xfffffd80623eb1b0)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  rw_enter+0x447 sys/kern/kern_rwlock.c:306
#2  rrw_enter+0x4f sys/kern/kern_rwlock.c:435
#3  VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615
#4  vn_lock+0x81 sys/kern/vfs_vnops.c:574
#5  vget+0x1c3 sys/kern/vfs_subr.c:672
#6  ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119
#7  ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1323
#8  ufs_lookup+0x14b4 sys/ufs/ufs/ufs_lookup.c:487
#9  VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:91
#10 vfs_lookup+0x7a6 sys/kern/vfs_lookup.c:568
#11 namei+0x63c sys/kern/vfs_lookup.c:249
#12 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785
#13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
#14 Xsyscall+0x128
exclusive rrwlock inode r = 0 (0xfffffd806ac6d1a8)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  rw_enter+0x447 sys/kern/kern_rwlock.c:306
#2  rrw_enter+0x4f sys/kern/kern_rwlock.c:435
#3  VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615
#4  vn_lock+0x81 sys/kern/vfs_vnops.c:574
#5  vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419
#6  namei+0x63c sys/kern/vfs_lookup.c:249
#7  dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785
#8  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#8  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
#9  Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim Kern Lim
         devbuf  9500   6526K    6913K  78643K     10876        0        0
            pcb    13      8K       8K  78643K        69        0        0
         rtable    96      3K       4K  78643K       252        0        0
         ifaddr    49     11K      12K  78643K        64        0        0
       counters    39     33K      33K  78643K        39        0        0
       ioctlops     0      0K       4K  78643K      1482        0        0
            iov     0      0K      16K  78643K        43        0        0
          mount     1      1K       1K  78643K         1        0        0
         vnodes  1215     76K      77K  78643K      1309        0        0
      UFS quota     1     32K      32K  78643K         1        0        0
      UFS mount     5     36K      36K  78643K         5        0        0
            shm     2      1K       5K  78643K         4        0        0
         VM map     2      1K       1K  78643K         3        0        0
            sem    12      1K       1K  78643K        13        0        0
        dirhash    12      2K       2K  78643K        12        0        0
           ACPI  1808    196K     290K  78643K     12765        0        0
      file desc     5     13K      25K  78643K       193        0        0
          sigio     0      0K       0K  78643K         1        0        0
           proc    61     63K      95K  78643K       462        0        0
        subproc    32      2K       2K  78643K        34        0        0
    NFS srvsock     1      0K       0K  78643K         1        0        0
     NFS daemon     1     16K      16K  78643K         1        0        0
    ip_moptions     0      0K       0K  78643K        25        0        0
       in_multi    29      1K       2K  78643K        42        0        0
    ether_multi     1      0K       0K  78643K         2        0        0
    ISOFS mount     1     32K      32K  78643K         1        0        0
  MSDOSFS mount     1     16K      16K  78643K         1        0        0
           ttys    36    159K     159K  78643K        36        0        0
           exec     0      0K       1K  78643K       225        0        0
        pagedep     1      8K       8K  78643K         1        0        0
       inodedep     1     32K      32K  78643K         1        0        0
         newblk     1      0K       0K  78643K         1        0        0
        VM swap     7     26K      26K  78643K         7        0        0
       UVM amap   103     21K      38K  78643K      1643        0        0
       UVM aobj    17      2K       2K  78643K        17        0        0
        memdesc     1      4K       4K  78643K         1        0        0
    crypto data     1      1K       1K  78643K         1        0        0
    ip6_options     0      0K       0K  78643K        40        0        0
            NDP     9      0K       0K  78643K        16        0        0
           temp   152   3559K    3632K  78643K      8926        0        0
         kqueue     0      0K       0K  78643K         2        0        0
      SYN cache     2     16K      16K  78643K         2        0        0
ddb{1}> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp         64        8    0        3     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       23    0       21     1     0     1     1     0     8    0
rtentry    112       51    0       13     2     0     2     2     0     8    0
unpcb      120      197    0      187     2     0     2     2     0     8    1
syncache   264        4    0        4     1     1     0     1     0     8    0
tcpqe       32       26    0       26     1     1     0     1     0     8    0
tcpcb      544      103    0       99     1     0     1     1     0     8    0
inpcb      280      321    0      313     2     0     2     2     0     8    1
nd6         48        4    0        1     1     0     1     1     0     8    0
pkpcb       40        4    0        4     1     0     1     1     0     8    1
ppxss      1128       3    0        3     2     1     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       25    0        1     1     0     1     1     0     8    0
pfstkey    112       25    0        1     1     0     1     1     0     8    0
pfstate    328       25    0        1     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      220    0        8    14     0    14    14     0     8    0
art_table   32      221    0        8     2     0     2     2     0     8    0
art_node    16       50    0       13     1     0     1     1     0     8    0
sysvmsgpl   40      125    0      120     1     0     1     1     0     8    0
semupl     112        3    0        3     1     1     0     1     0     8    0
semapl     112       11    0        1     1     0     1     1     0     8    0
shmpl      112       15    0        0     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128     1742    0      336    46     0    46    46     0     8    0
ffsino     272     1742    0      336    95     0    95    95     0     8    0
nchpl      144     2262    0      645    61     0    61    61     0     8    0
uvmvnodes   72     1849    0        0    34     0    34    34     0     8    0
vnodes     208     1849    0        0    98     0    98    98     0     8    0
namei      1024    6115    0     6115     1     0     1     1     0     8    1
percpumem   16       30    0        0     1     0     1     1     0     8    0
vmpool     552        1    0        1     1     1     0     1     0     8    0
scxspl     192     7056    0     7055     8     3     5     7     0     8    4
plimitpl   152       31    0       23     1     0     1     1     0     8    0
sigapl     432      394    0      379     3     1     2     3     0     8    0
futexpl     56     4115    0     4115     1     0     1     1     0     8    1
knotepl    112       65    0       46     1     0     1     1     0     8    0
kqueuepl   104       26    0       24     1     0     1     1     0     8    0
pipepl     112      248    0      227     2     1     1     2     0     8    0
fdescpl    488      395    0      379     3     0     3     3     0     8    0
filepl     152     2667    0     2564     6     0     6     6     0     8    1
lockfpl    104      319    0      318     1     0     1     1     0     8    0
lockfspl    48       84    0       83     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      150    0      141     1     0     1     1     0     8    0
zombiepl   144      379    0      379     1     0     1     1     0     8    1
processpl  896      411    0      379     4     0     4     4     0     8    0
procpl     632      859    0      817     5     0     5     5     0     8    1
sosppl     128        4    0        4     1     0     1     1     0     8    1
sockpl     384      547    0      527     6     0     6     6     0     8    4
mcl64k     65536      5    0        0     1     0     1     1     0     8    0
mcl16k     16384      5    0        0     1     0     1     1     0     8    0
mcl12k     12288      1    0        0     1     0     1     1     0     8    0
mcl9k      9216       3    0        0     1     0     1     1     0     8    0
mcl8k      8192       3    0        0     1     0     1     1     0     8    0
mcl4k      4096       5    0        0     1     0     1     1     0     8    0
mcl2k      2048     150    0        0    18     0    18    18     0     8    0
mtagpl      80        8    0        0     1     0     1     1     0     8    0
mbufpl     256      177    0        0    11     0    11    11     0     8    0
bufpl      256     6988    0     1318   355     0   355   355     0     8    0
anonpl      16    57877    0    38652    88     1    87    87     0   124    8
amapchunkpl 152    2389    0     2260    11     0    11    11     0   158    5
amappl16   192     1853    0      780    55     0    55    55     0     8    1
amappl15   184      169    0      165     1     0     1     1     0     8    0
amappl14   176       27    0       26     1     0     1     1     0     8    0
amappl13   168        7    0        4     1     0     1     1     0     8    0
amappl12   160       11    0       10     2     1     1     1     0     8    0
amappl11   152       53    0       38     1     0     1     1     0     8    0
amappl10   144       93    0       86     1     0     1     1     0     8    0
amappl9    136      620    0      614     1     0     1     1     0     8    0
amappl8    128      174    0      149     1     0     1     1     0     8    0
amappl7    120      114    0      109     1     0     1     1     0     8    0
amappl6    112       75    0       65     1     0     1     1     0     8    0
amappl5    104      137    0      123     1     0     1     1     0     8    0
amappl4     96      669    0      635     1     0     1     1     0     8    0
amappl3     88      118    0      113     1     0     1     1     0     8    0
amappl2     80     2337    0     2263     3     1     2     3     0     8    0
amappl1     72    18613    0    18179    26    16    10    20     0     8    0
amappl      80     1118    0     1079     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       17    0       17     1     1     0     1     0     8    0
aobjpl      64       16    0        0     1     0     1     1     0     8    0
uaddrrnd    24      396    0      379     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      396    0      379     1     0     1     1     0     8    0
vmmpekpl   168     7243    0     7207     2     0     2     2     0     8    0
vmmpepl    168    55862    0    53655   134    16   118   127     0   357   16
vmsppl     368      394    0      379     2     0     2     2     0     8    0
pdppl      4096     799    0      760     6     0     6     6     0     8    0
pvpl        32   183071    0   160683   209     0   209   209     0   265   24
pmappl     232      395    0      380     2     1     1     2     0     8    0
extentpl    40       41    0       26     1     0     1     1     0     8    0
phpool     112      515    0        3    15     0    15    15     0     8    0

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/22 22:15 openbsd 2c98785eaaa1 a2bdbd8c .config console log report ci-openbsd-multicore
2019/10/18 22:57 openbsd 754f2b84d7f3 8c88c9c1 .config console log report ci-openbsd-multicore
2019/10/15 17:16 openbsd 63effaba6423 b5268b89 .config console log report ci-openbsd-multicore
2019/10/06 13:53 openbsd f78cba616245 f3f7d9c8 .config console log report ci-openbsd-multicore
2019/10/02 05:28 openbsd 18ccf01191d1 b7a87a83 .config console log report ci-openbsd-multicore
2019/09/18 13:42 openbsd dd27a1761061 14d41584 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.