syzbot


assert "rt->rt_ifa->ifa_ifp != NULL" failed: file "/sypzaknic: kernel diagnostic assertion "!_kernel_lock_held()" failed

Status: closed as dup on 2019/11/06 08:14
Reported-by: syzbot+a258da51529f785dcdb5@syzkaller.appspotmail.com
First crash: 1843d, last: 1843d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
assert "rt->rt_ifa->ifa_ifp != NULL" failed in route.c 830 1841d 1882d

Sample crash report:
panic: kernel diagnostic assertion "rt->rt_ifa->ifa_ifp != NULL" failed: file "/sypzaknic: kernel diagnostic assertion "!_kernel_lock_held()" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_fork.c", line 683
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 389753  40397      0           0  0x4000000    0  syz-executor.0
* 47872  98206      0           0  0x4000000    1  syz-executor.1
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
__assert(ffffffff82208f7b,ffffffff821f7b24,2ab,ffffffff821db16e) at __assert+0x2b sys/kern/subr_prf.c:154
proc_trampoline_mp() at proc_trampoline_mp+0x123
end trace frame: 0x0, count: 11
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
kernel diagnostic assertion "rt->rt_ifa->ifa_ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/route.c", line 848
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
__assert(ffffffff82208f7b,ffffffff821f7b24,2ab,ffffffff821db16e) at __assert+0x2b sys/kern/subr_prf.c:154
proc_trampoline_mp() at proc_trampoline_mp+0x123
end trace frame: 0x0, count: -4
ddb{1}> show registers
rdi                                0
rsi                              0x1
rbp               0xffff8000229b3a90
rbx               0xffff8000229b3b40
rdx               0xffff800020ace510
rcx                                0
rax                                0
r8                0xffffffff8141f94f    kprintf+0x16f
r9                               0x1
r10                             0x25
r11               0xa49da2ace6c58054
r12                     0x3000000008
r13               0xffff8000229b3aa0
r14                            0x104
r15                              0x1
rip               0xffffffff814c4808    db_enter+0x18
cs                               0x8
rflags                         0x246
rsp               0xffff8000229b3a80
ss                              0x10
db_enter+0x18:  addq    $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor.1) pid=47872 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=86, usrpri=86, nice=20
    forw=0xffffffffffffffff, list=0xffff800020ace020,0xffff800020ace2a8
    process=0xffff800020a8ae10 user=0xffff8000229ae000, vmspace=0xfffffd807f00a000
    estcpu=36, cpticks=1, pctcpu=0.0
    user=0, sys=1, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 40397  485393  39961      0  2           0                syz-executor.0
 40397  389753  39961      0  7   0x4000000                syz-executor.0
 98206  416742  25413      0  2           0                syz-executor.1
 98206  254137  25413      0  3   0x4000080  ttyopn        syz-executor.1
*98206   47872  25413      0  7   0x4000000                syz-executor.1
 39961  382675  94410      0  3        0x82  nanosleep     syz-executor.0
 25413  100062  94410      0  3        0x82  nanosleep     syz-executor.1
 97352  217465      1      0  3    0x100083  ttyin         getty
 21685  467806      0      0  3     0x14200  acct          acct
 43761  492664      0      0  3     0x14200  bored         sosplice
 94410  406449  11905      0  3        0x82  thrsleep      syz-fuzzer
 94410   16626  11905      0  3   0x4000082  nanosleep     syz-fuzzer
 94410  312377  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410   68394  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410  114608  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410  166111  11905      0  3   0x4000082  kqread        syz-fuzzer
 94410  353932  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410  196601  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410  503736  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 94410  417591  11905      0  3   0x4000082  thrsleep      syz-fuzzer
 11905  192354  56555      0  3    0x10008a  pause         ksh
 56555  307654  57878      0  3        0x92  select        sshd
 57878  384198      1      0  3        0x80  select        sshd
 89081  366118  98837     74  3    0x100092  bpf           pflogd
 98837  419610      1      0  3        0x80  netio         pflogd
 99176  415358  28869     73  3    0x100090  kqread        syslogd
 28869   59203      1      0  3    0x100082  netio         syslogd
 76223  372154      1     77  3    0x100090  poll          dhclient
 78988  266099      1      0  3        0x80  poll          dhclient
 38579  176744      0      0  2     0x14200                zerothread
 84157  272151      0      0  3     0x14200  aiodoned      aiodoned
 90588  169391      0      0  3     0x14200  syncer        update
 95545  508919      0      0  3     0x14200  cleaner       cleaner
 62330  508964      0      0  3     0x14200  reaper        reaper
 79048  465292      0      0  3     0x14200  pgdaemon      pagedaemon
 10057  220730      0      0  3     0x14200  bored         crynlk
 76188  470386      0      0  3     0x14200  bored         crypto
 22764  309941      0      0  3  0x40014200  acpi0         acpi0
 72535  394288      0      0  3  0x40014200                idle1
 67513  432652      0      0  3     0x14200  bored         softnet
 54472  204508      0      0  3     0x14200  bored         systqmp
 96897  371193      0      0  3     0x14200  bored         systq
 87750   37598      0      0  3  0x40014200  bored         softclock
  1811  387824      0      0  3  0x40014200                idle0
 96299  369692      0      0  3     0x14200  pause         smr
     1  194561      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 40397 (syz-executor.0) thread 0xffff800020ace298 (389753)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82648ec0)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  rt_clone+0x5c sys/net/route.c:266
#2  rtalloc_mpath+0xba rt_match sys/net/route.c:244 [inline]
#2  rtalloc_mpath+0xba sys/net/route.c:359
#3  ip_output+0x4f2 sys/netinet/ip_output.c:204
#4  rip_output+0x252 sys/netinet/raw_ip.c:289
#5  rip_usrreq+0x46a sys/netinet/raw_ip.c:538
#6  sosend+0x645 sys/kern/uipc_socket.c:524
#7  dofilewritev+0x1b7 sys/kern/sys_generic.c:364
#8  sys_write+0x83 sys/kern/sys_generic.c:284
#9  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#9  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
#10 Xsyscall+0x128
exclusive rwlock netlock r = 0 (0xffffffff824dc718)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1163
#1  solock+0x5a sys/kern/uipc_socket2.c:282
#2  sosend+0x51b sys/kern/uipc_socket.c:512
#3  dofilewritev+0x1b7 sys/kern/sys_generic.c:364
#4  sys_write+0x83 sys/kern/sys_generic.c:284
#5  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#5  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555
#6  Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim Kern Lim
         devbuf  9647   6486K   15068K  78643K     52381        0        0
            pcb    13     12K      14K  78643K      1674        0        0
         rtable   173     17K      18K  78643K      4851        0        0
         ifaddr   120     30K      33K  78643K      1467        0        0
       counters    39     33K      33K  78643K        39        0        0
       ioctlops     0      0K       4K  78643K      1818        0        0
            iov     0      0K      32K  78643K      1784        0        0
          mount     1      1K       1K  78643K         1        0        0
         vnodes  1236     78K      79K  78643K     13366        0        0
      UFS quota     1     32K      32K  78643K         1        0        0
      UFS mount     5     36K      36K  78643K         5        0        0
            shm     2      1K       9K  78643K       117        0        0
         VM map    51     25K      25K  78643K        78        0        0
            sem    12      0K       1K  78643K      3009        0        0
        dirhash    12      2K       2K  78643K        12        0        0
           ACPI  1808    196K     290K  78643K     12765        0        0
      file desc     6     17K      25K  78643K      7369        0        0
          sigio     1      0K       0K  78643K       112        0        0
           proc    62     63K      95K  78643K      3312        0        0
        subproc    32      2K       2K  78643K       837        0        0
    NFS srvsock     1      0K       0K  78643K         1        0        0
     NFS daemon     1     16K      16K  78643K         1        0        0
    ip_moptions     0      0K       1K  78643K       684        0        0
       in_multi    38      2K       3K  78643K      1045        0        0
    ether_multi     1      0K       0K  78643K        99        0        0
            mrt     0      0K       0K  78643K        53        0        0
    ISOFS mount     1     32K      32K  78643K         1        0        0
  MSDOSFS mount     1     16K      16K  78643K         1        0        0
           ttys   108    477K     477K  78643K       108        0        0
           exec     0      0K       1K  78643K      1773        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   225    389K     394K  78643K     27044        0        0
       UVM aobj   130      4K       4K  78643K       136        0        0
        memdesc     1      4K       4K  78643K         1        0        0
    crypto data     1      1K       1K  78643K         1        0        0
    ip6_options     0      0K       1K  78643K      1696        0        0
            NDP    25      0K       1K  78643K       473        0        0
           temp   264   3561K    4201K  78643K    246448        0        0
         kqueue     0      0K       0K  78643K        85        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      118    0      113     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80      613    0      611     1     0     1     1     0     8    0
rtentry    112      858    0      790     3     0     3     3     0     8    0
unpcb      120     5625    0     5604    15    14     1     2     0     8    0
syncache   264       47    0       47    20    20     0     1     0     8    0
tcpqe       32      121    0      121     8     8     0     1     0     8    0
tcpcb      544     4968    0     4964    39    37     2    12     0     8    1
inpcb      280    13027    0    13019    55    53     2    13     0     8    1
rttmr       72       16    0       15     3     2     1     1     0     8    0
ip6q        72        2    0        2     2     2     0     1     0     8    0
ip6af       40        2    0        2     1     1     0     1     0     8    0
nd6         48      135    0      133     3     2     1     1     0     8    0
pkpcb       40       27    0       27    10    10     0     1     0     8    0
swfcl       56        3    0        0     1     0     1     1     0     8    0
ppxss      1128     209    0      209    25    24     1     1     0     8    1
pffrag     232      199    0      199    37    36     1     1     0   482    1
pffrnode    88      199    0      199    37    36     1     1     0     8    1
pffrent     40     6853    0     6853    37    36     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      603    0      567     1     0     1     1     0     8    0
pfstkey    112      603    0      567     3     1     2     3     0     8    0
pfstate    328      603    0      566     9     4     5     8     0     8    0
pfrule     1360      21    0       16     2     1     1     2     0     8    0
art_heap8  4096      19    0       13    17    11     6     6     0     8    0
art_heap4  256     3706    0     3422    51    31    20    22     0     8    0
art_table   32     3725    0     3435     7     4     3     3     0     8    0
art_node    16      852    0      803     1     0     1     1     0     8    0
sysvmsgpl   40       23    0       12     1     0     1     1     0     8    0
semupl     112        1    0        1     1     1     0     1     0     8    0
semapl     112     3007    0     2997     1     0     1     1     0     8    0
shmpl      112      134    0        6     4     0     4     4     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128    12823    0    11390    49     2    47    47     0     8    0
ffsino     272    12823    0    11390    97     1    96    96     0     8    0
nchpl      144    26151    0    25654    61    41    20    61     0     8    0
uvmvnodes   72     6398    0        0   117     0   117   117     0     8    0
vnodes     208     6398    0        0   337     0   337   337     0     8    0
namei      1024   97400    0    97400     3     2     1     1     0     8    1
percpumem   16       30    0        0     1     0     1     1     0     8    0
vcpupl     1984      49    0        0     7     0     7     7     0     8    0
vmpool     552       76    0       27     4     0     4     4     0     8    0
scsiplug    64        9    0        9     6     6     0     1     0     8    0
scxspl     192    78017    0    78017    57    54     3     3     0     8    3
plimitpl   152      682    0      674     1     0     1     1     0     8    0
sigapl     432     7432    0     7416     3     1     2     3     0     8    0
futexpl     56   190814    0   190814     2     1     1     1     0     8    1
knotepl    112     1504    0     1485     5     4     1     2     0     8    0
kqueuepl   104     2129    0     2127     7     6     1     4     0     8    0
pipepl     112     4660    0     4641     4     3     1     2     0     8    0
fdescpl    488     7433    0     7416     3     0     3     3     0     8    0
filepl     152    75293    0    75191    71    65     6    14     0     8    2
lockfpl    104     2796    0     2795     1     0     1     1     0     8    0
lockfspl    48      923    0      922     1     0     1     1     0     8    0
sessionpl  112       71    0       60     1     0     1     1     0     8    0
pgrppl      48      180    0      169     1     0     1     1     0     8    0
ucredpl     96     8416    0     8406     1     0     1     1     0     8    0
zombiepl   144     7416    0     7416     2     1     1     1     0     8    1
processpl  896     7450    0     7416     4     0     4     4     0     8    0
procpl     632    23592    0    23546     5     0     5     5     0     8    0
srpgc       64       90    0       90    29    28     1     1     0     8    1
sosppl     128      279    0      279    31    30     1     1     0     8    1
sockpl     384    19512    0    19479   101    96     5    23     0     8    0
mcl64k     65536    925    0        0   100    35    65    66     0     8    0
mcl16k     16384     33    0        0     5     2     3     3     0     8    0
mcl12k     12288     41    0        0     2     0     2     2     0     8    0
mcl9k      9216      27    0        0     2     0     2     2     0     8    0
mcl8k      8192      33    0        0     5     2     3     3     0     8    0
mcl4k      4096      25    0        0     3     0     3     3     0     8    0
mcl2k2     2112      11    0        0     1     0     1     1     0     8    0
mcl2k      2048     202    0        0    20     3    17    20     0     8    0
mtagpl      80       99    0        0     1     0     1     1     0     8    0
mbufpl     256     1274    0        0    51     0    51    51     0     8    0
bufpl      256    28809    0    21751   442     0   442   442     0     8    0
anonpl      16   959732    0   935188   268   163   105   116     0   124    1
amapchunkpl 152   57982    0    57553   133   110    23    31     0   158    5
amappl16   192    40286    0    39131   281   221    60    71     0     8    0
amappl15   184      748    0      747     6     5     1     1     0     8    0
amappl14   176      916    0      911     1     0     1     1     0     8    0
amappl13   168      743    0      742     1     0     1     1     0     8    0
amappl12   160     2111    0     2106     1     0     1     1     0     8    0
amappl11   152      566    0      551     1     0     1     1     0     8    0
amappl10   144     1529    0     1520     1     0     1     1     0     8    0
amappl9    136     2245    0     2241     1     0     1     1     0     8    0
amappl8    128     1933    0     1847     3     0     3     3     0     8    0
amappl7    120     1711    0     1700     1     0     1     1     0     8    0
amappl6    112      457    0      441     1     0     1     1     0     8    0
amappl5    104     2643    0     2628     1     0     1     1     0     8    0
amappl4     96     6808    0     6772     1     0     1     1     0     8    0
amappl3     88     2040    0     2035     1     0     1     1     0     8    0
amappl2     80    56605    0    56516     3     1     2     3     0     8    0
amappl1     72   177332    0   176876    25    15    10    20     0     8    0
amappl      80    24859    0    24784     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      135    0        6     3     0     3     3     0     8    0
uaddrrnd    24     7509    0     7416     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24     7509    0     7416     1     0     1     1     0     8    0
vmmpekpl   168    61171    0    61128     3     0     3     3     0     8    0
vmmpepl    168   960000    0   957433   498   343   155   164     0   357   35
vmsppl     368     7432    0     7416     2     0     2     2     0     8    0
pdppl      4096   15025    0    14935    13     1    12    12     0     8    0
pvpl        32  2455936    0  2432421   512   310   202   231     0   265    0
pmappl     232     7508    0     7443     5     1     4     4     0     8    0
extentpl    40       41    0       26     1     0     1     1     0     8    0
phpool     112      855    0      128    21     0    21    21     0     8    0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/06 02:22 openbsd 38dc29e6b4c8 bc2c6e45 .config console log report ci-openbsd-multicore
* Struck through repros no longer work on HEAD.