syzbot


assert "frag->fr_firstoff[index] != NULL" failed in pf_norm.c

Status: fixed on 2021/02/23 00:42
Reported-by: syzbot+d043455a5346f726f1c4@syzkaller.appspotmail.com
Fix commit: be7274bff2cd When cutting of the head of an overlapping fragment during pf reassembly, reinsert the fragment into the lookup table with correct index. Reported-by: syzbot+d043455a5346f726f1c4@syzkaller.appspotmail.com OK claudio@
First crash: 669d, last: 650d

Sample crash report:
panic: kernel diagnostic assertion "frag->fr_firstoff[index] != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/pf_norm.c", line 439
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*327096  73083      0           0          0    1K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823c5187) at panic+0x15e sys/kern/subr_prf.c:218
__assert(ffffffff82433244,ffffffff82451ec5,1b7,ffffffff823b74a3) at __assert+0x2b sys/kern/subr_prf.c:162
pf_frent_remove(fffffd806b658e80,fffffd806b659f50) at pf_frent_remove+0x2a4 sys/net/pf_norm.c:460
pf_fillup_fragment(ffff80002129cc98,0,fffffd806b659f00,ffff80002129cede) at pf_fillup_fragment+0xbeb sys/net/pf_norm.c:679
pf_reassemble(ffff80002129ce10,1,ffff80002129cede) at pf_reassemble+0xeb sys/net/pf_norm.c:781
pf_normalize_ip(ffff80002129cdd0,ffff80002129cede) at pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
pf_test(2,1,ffff800000ae3000,ffff80002129cfe8) at pf_test+0x397
ip_input_if(ffff80002129cfe8,ffff80002129cff4,4,0,ffff800000ae3000) at ip_input_if+0x578 sys/netinet/ip_input.c:338
ipv4_input(ffff800000ae3000,fffffd806d720f00) at ipv4_input+0x48 sys/netinet/ip_input.c:237
tun_dev_write(5d00,ffff80002129d2d8,11,2) at tun_dev_write+0x204 sys/net/if_tun.c:870
spec_write(ffff80002129d130) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806e4165c8,ffff80002129d2d8,11,fffffd807f7b7c60) at VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
vn_write(fffffd806cd0cbf0,ffff80002129d2d8,0) at vn_write+0x14e sys/kern/vfs_vnops.c:414
end trace frame: 0xffff80002129d2c0, count: 0
https://www.openbsd.org/ddb.html describes the minimum info required in bug
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ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
kernel diagnostic assertion "frag->fr_firstoff[index] != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/pf_norm.c", line 439
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823c5187) at panic+0x15e sys/kern/subr_prf.c:218
__assert(ffffffff82433244,ffffffff82451ec5,1b7,ffffffff823b74a3) at __assert+0x2b sys/kern/subr_prf.c:162
pf_frent_remove(fffffd806b658e80,fffffd806b659f50) at pf_frent_remove+0x2a4 sys/net/pf_norm.c:460
pf_fillup_fragment(ffff80002129cc98,0,fffffd806b659f00,ffff80002129cede) at pf_fillup_fragment+0xbeb sys/net/pf_norm.c:679
pf_reassemble(ffff80002129ce10,1,ffff80002129cede) at pf_reassemble+0xeb sys/net/pf_norm.c:781
pf_normalize_ip(ffff80002129cdd0,ffff80002129cede) at pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
pf_test(2,1,ffff800000ae3000,ffff80002129cfe8) at pf_test+0x397
ip_input_if(ffff80002129cfe8,ffff80002129cff4,4,0,ffff800000ae3000) at ip_input_if+0x578 sys/netinet/ip_input.c:338
ipv4_input(ffff800000ae3000,fffffd806d720f00) at ipv4_input+0x48 sys/netinet/ip_input.c:237
tun_dev_write(5d00,ffff80002129d2d8,11,2) at tun_dev_write+0x204 sys/net/if_tun.c:870
spec_write(ffff80002129d130) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806e4165c8,ffff80002129d2d8,11,fffffd807f7b7c60) at VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
vn_write(fffffd806cd0cbf0,ffff80002129d2d8,0) at vn_write+0x14e sys/kern/vfs_vnops.c:414
dofilewritev(ffff8000212817a0,f0,ffff80002129d2d8,0,ffff80002129d3c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365
sys_write(ffff8000212817a0,ffff80002129d370,ffff80002129d3c0) at sys_write+0x83 sys/kern/sys_generic.c:285
syscall(ffff80002129d440) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff80002129d440) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffc1860, count: -18
ddb{1}> show registers
rdi                                0
rsi                              0x1
rbp               0xffff80002129cab0
rbx               0xffff80002129cac0
rdx                             0x8b
rcx                              0x2
rax                              0x1
r8                0xffffffff81653205    kprintf+0x145
r9                               0x1
r10               0x5ed2bd1b7d6139da
r11               0xfc8e09565f7bd919
r12                     0x3000000008
r13               0xffff80002129cb60
r14                            0x100
r15                              0x1
rip               0xffffffff81b2dcc8    db_enter+0x18
cs                               0x8
rflags                         0x246
rsp               0xffff80002129caa0
ss                              0x10
db_enter+0x18:  addq    $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor.0) pid=327096 stat=onproc
    flags process=0 proc=0
    pri=50, usrpri=50, nice=20
    forw=0xffffffffffffffff, list=0xffff8000211c22a8,0xffffffff82943318
    process=0xffff800021235d98 user=0xffff800021298000, vmspace=0xfffffd800849e5c0
    estcpu=36, cpticks=2, pctcpu=0.0
    user=0, sys=2, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
*73083  327096  23667      0  7           0                syz-executor.0
 23667  198106   1937      0  3        0x82  nanoslp       syz-executor.0
  1937  250687  73285      0  3        0x82  kqread        syz-execprog
  1937  339588  73285      0  3   0x4000082  nanoslp       syz-execprog
  1937  229541  73285      0  3   0x4000082  thrsleep      syz-execprog
  1937  334544  73285      0  3   0x4000082  thrsleep      syz-execprog
  1937   90499  73285      0  3   0x4000082  thrsleep      syz-execprog
  1937  370423  73285      0  3   0x4000082  thrsleep      syz-execprog
  1937  143409  73285      0  3   0x4000082  thrsleep      syz-execprog
 73285  398644   5276      0  3    0x10008a  sigsusp       ksh
  5276  203550  47274      0  3        0x92  select        sshd
 28696  435636      1      0  3    0x100083  ttyin         getty
 47274  219090      1      0  3        0x80  select        sshd
 74619   78993  45765     74  3    0x100092  bpf           pflogd
 45765  498420      1      0  3        0x80  netio         pflogd
 72164  520681  92592     73  3    0x100090  kqread        syslogd
 92592  213831      1      0  3    0x100082  netio         syslogd
 19657   63811      1     77  3    0x100090  poll          dhclient
 52188  410365      1      0  3        0x80  poll          dhclient
 23286  227871      0      0  3     0x14200  bored         smr
 42280  500755      0      0  3     0x14200  pgzero        zerothread
 83553  173139      0      0  3     0x14200  aiodoned      aiodoned
 87772  382750      0      0  3     0x14200  syncer        update
 81734  237527      0      0  3     0x14200  cleaner       cleaner
 55478  450446      0      0  3     0x14200  reaper        reaper
  6501   93921      0      0  3     0x14200  pgdaemon      pagedaemon
 40419  414578      0      0  3     0x14200  bored         crynlk
 43395  321355      0      0  3     0x14200  bored         crypto
 67065  310922      0      0  3     0x14200  bored         viomb
 38418  216830      0      0  3  0x40014200  acpi0         acpi0
 72986  267605      0      0  3  0x40014200                idle1
 49067  139088      0      0  3     0x14200  bored         softnet
 94714  427104      0      0  3     0x14200  bored         systqmp
 51196   58092      0      0  3     0x14200  bored         systq
 69874  514373      0      0  3  0x40014200  bored         softclock
 98738   37400      0      0  7  0x40014200                idle0
     1  385655      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
CPU 1:
exclusive mutex &pf_frag_mtx r = 0 (0xffffffff8284ac58)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1  mtx_enter_try+0x100
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pf_reassemble+0xd5 sys/net/pf_norm.c:780
#4  pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
#5  pf_test+0x397
#6  ip_input_if+0x578 sys/netinet/ip_input.c:338
#7  ipv4_input+0x48 sys/netinet/ip_input.c:237
#8  tun_dev_write+0x204 sys/net/if_tun.c:870
#9  spec_write+0xd4 sys/kern/spec_vnops.c:309
#10 VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
#11 vn_write+0x14e sys/kern/vfs_vnops.c:414
#12 dofilewritev+0x1ab sys/kern/sys_generic.c:365
#13 sys_write+0x83 sys/kern/sys_generic.c:285
#14 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#14 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
#15 Xsyscall+0x128
Process 73083 (syz-executor.0) thread 0xffff8000212817a0 (327096)
exclusive rwlock netlock r = 0 (0xffffffff82728fd0)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1  tun_dev_write+0x1f9 sys/net/if_tun.c:869
#2  spec_write+0xd4 sys/kern/spec_vnops.c:309
#3  VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
#4  vn_write+0x14e sys/kern/vfs_vnops.c:414
#5  dofilewritev+0x1ab sys/kern/sys_generic.c:365
#6  sys_write+0x83 sys/kern/sys_generic.c:285
#7  syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#7  syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
#8  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff828f1fa0)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1  vn_write+0x42 sys/kern/vfs_vnops.c:399
#2  dofilewritev+0x1ab sys/kern/sys_generic.c:365
#3  sys_write+0x83 sys/kern/sys_generic.c:285
#4  syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#4  syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
#5  Xsyscall+0x128
exclusive mutex &pf_frag_mtx r = 0 (0xffffffff8284ac58)
#0  witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline]
#0  witness_lock+0x4b0 sys/kern/subr_witness.c:1182
#1  mtx_enter_try+0x100
#2  mtx_enter+0x4b sys/kern/kern_lock.c:266
#3  pf_reassemble+0xd5 sys/net/pf_norm.c:780
#4  pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
#5  pf_test+0x397
#6  ip_input_if+0x578 sys/netinet/ip_input.c:338
#7  ipv4_input+0x48 sys/netinet/ip_input.c:237
#8  tun_dev_write+0x204 sys/net/if_tun.c:870
#9  spec_write+0xd4 sys/kern/spec_vnops.c:309
#10 VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
#11 vn_write+0x14e sys/kern/vfs_vnops.c:414
#12 dofilewritev+0x1ab sys/kern/sys_generic.c:365
#13 sys_write+0x83 sys/kern/sys_generic.c:285
#14 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#14 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
#15 Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9478   6414K    6414K  78643K     10568        0
            pcb    13      8K       8K  78643K        13        0
         rtable    83      2K       2K  78643K       157        0
         ifaddr    37      9K       9K  78643K        38        0
       counters    42     33K      33K  78643K        42        0
       ioctlops     0      0K       4K  78643K      1468        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1183     74K      75K  78643K      1188        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     2      0K       0K  78643K         2        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1697    195K     286K  78643K     12598        0
      file desc     3      8K      12K  78643K        19        0
           proc    59     63K      83K  78643K       397        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
       in_multi    22      1K       1K  78643K        22        0
    ether_multi     1      0K       0K  78643K         1        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    19     95K      95K  78643K        19        0
           exec     0      0K       2K  78643K       337        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    59     11K      11K  78643K       703        0
       UVM aobj     3      2K       2K  78643K         3        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
            NDP     7      0K       0K  78643K         7        0
           temp    28   3961K    4025K  78643K      1893        0
         kqueue     3      4K       4K  78643K         3        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        4    0        0     1     0     1     1     0     8    0
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb      120       17    0       15     1     0     1     1     0     8    0
rtentry    112       34    0        1     1     0     1     1     0     8    0
unpcb      120       29    0       19     1     0     1     1     0     8    0
syncache   296        5    0        5     2     1     1     1     0     8    1
tcpcb      736        8    0        5     1     0     1     1     0     8    0
inpcb      304       32    0       27     1     0     1     1     0     8    0
nd6         48        3    0        0     1     0     1     1     0     8    0
pffrag     232        1    0        0     1     0     1     1     0   482    0
pffrnode    88        1    0        0     1     0     1     1     0     8    0
pffrent     40        3    0        0     1     0     1     1     0     8    0
pfosfp      40     1428    0     1005     5     0     5     5     0     8    0
pfosfpen   112     1428    0      714    21     0    21    21     0     8    0
pfstitem    24       11    0        0     1     0     1     1     0     8    0
pfstkey    112       11    0        0     1     0     1     1     0     8    0
pfstate    320       11    0        0     1     0     1     1     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      145    0        0    10     0    10    10     0     8    0
art_table   32      146    0        0     2     0     2     2     0     8    0
art_node    16       33    0        3     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1423    0       23    88     0    88    88     0     8    0
ffsino     272     1423    0       23    94     0    94    94     0     8    0
nchpl      144     1640    0       42    61     1    60    60     0     8    0
uvmvnodes   72     1433    0        0    27     0    27    27     0     8    0
vnodes     224     1433    0        0    85     0    85    85     0     8    0
namei      1024    4170    0     4170     2     1     1     1     0     8    1
percpumem   16       32    0        0     1     0     1     1     0     8    0
scxspl     216     4592    0     4592     2     1     1     2     0     8    1
plimitpl   152       15    0        8     1     0     1     1     0     8    0
sigapl     424      242    0      211     4     0     4     4     0     8    0
knotepl    112       48    0       36     1     0     1     1     0     8    0
kqueuepl   168        2    0        0     1     0     1     1     0     8    0
pipepl     336       78    0       70     2     1     1     1     0     8    0
fdescpl    496      226    0      211     3     0     3     3     0     8    0
filepl     152     1071    0     1012     3     0     3     3     0     8    0
lockfpl    104        5    0        4     1     0     1     1     0     8    0
lockfspl    48        3    0        2     1     0     1     1     0     8    0
sessionpl  144       19    0        9     1     0     1     1     0     8    0
pgrppl      48       19    0        9     1     0     1     1     0     8    0
ucredpl     96       62    0       53     1     0     1     1     0     8    0
zombiepl   144      211    0      211     2     1     1     1     0     8    1
processpl  1080     242    0      211     3     0     3     3     0     8    0
procpl     672      248    0      211     4     0     4     4     0     8    0
sockpl     432       78    0       61     4     1     3     3     0     8    0
mcl4k      4096       1    0        0     1     0     1     1     0     8    0
mcl2k      2048      80    0        0    10     0    10    10     0     8    0
mtagpl      96        1    0        0     1     0     1     1     0     8    0
mbufpl     256       97    0        0     6     0     6     6     0     8    0
bufpl      280     3246    0      167   220     0   220   220     0     8    0
anonpl      24    23483    0    21343    25     3    22    22     0   186    7
amapchunkpl 152     860    0      779     6     1     5     5     0   158    1
amappl16   200      164    0      108     4     0     4     4     0     8    0
amappl15   192        2    0        1     1     0     1     1     0     8    0
amappl13   176       26    0       22     2     1     1     1     0     8    0
amappl12   168       39    0       33     1     0     1     1     0     8    0
amappl11   160       46    0       33     1     0     1     1     0     8    0
amappl10   152       14    0        6     1     0     1     1     0     8    0
amappl9    144      236    0      235     2     1     1     1     0     8    0
amappl8    136      258    0      245     2     1     1     1     0     8    0
amappl7    128       59    0       53     1     0     1     1     0     8    0
amappl6    120       84    0       74     1     0     1     1     0     8    0
amappl5    112      148    0      136     1     0     1     1     0     8    0
amappl4    104      520    0      495     1     0     1     1     0     8    0
amappl3     96      129    0      119     1     0     1     1     0     8    0
amappl2     88      945    0      890     3     1     2     2     0     8    0
amappl1     80    15415    0    14973    28     7    21    21     0     8   10
amappl      88      474    0      443     1     0     1     1     0    92    0
dma4096    4096       1    0        1     1     1     0     1     0     8    0
dma1024    1024       1    0        0     1     0     1     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        2    0        0     1     0     1     1     0     8    0
uaddrrnd    24      226    0      211     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      226    0      211     1     0     1     1     0     8    0
vmmpekpl   168     6387    0     6369     1     0     1     1     0     8    0
vmmpepl    168    33502    0    32497    89    13    76    76     0   357   32
vmsppl     368      225    0      211     2     0     2     2     0     8    0
rwobjpl     56     9102    0     8456    25     6    19    19     0     8    8
pdppl      4096     459    0      422    55    14    41    41     0     8    4
pvpl        32   117691    0   112901   119     3   116   116     0   265   76
pmappl     232      225    0      211     1     0     1     1     0     8    0
extentpl    40       58    0       40     1     0     1     1     0     8    0
phpool     112      280    0       19     8     0     8     8     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x1a:        addq    $0x8,%rsp
x86_ipi_db(ffffffff8272eff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__mp_lock(ffffffff828f1d98) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff828f1d98) at __mp_lock+0x122 sys/kern/kern_lock.c:147
softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:90
Xsoftclock() at Xsoftclock+0x1f
acpicpu_idle() at acpicpu_idle+0x2eb sys/dev/acpi/acpicpu.c:1206
sched_idle(ffffffff8272eff0) at sched_idle+0x417 sys/kern/kern_sched.c:178
end trace frame: 0x0, count: 7
ddb{0}> trace
x86_ipi_db(ffffffff8272eff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__mp_lock(ffffffff828f1d98) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff828f1d98) at __mp_lock+0x122 sys/kern/kern_lock.c:147
softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:90
Xsoftclock() at Xsoftclock+0x1f
acpicpu_idle() at acpicpu_idle+0x2eb sys/dev/acpi/acpicpu.c:1206
sched_idle(ffffffff8272eff0) at sched_idle+0x417 sys/kern/kern_sched.c:178
end trace frame: 0x0, count: -8
ddb{0}> machine ddbcpu 1
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823c5187) at panic+0x15e sys/kern/subr_prf.c:218
__assert(ffffffff82433244,ffffffff82451ec5,1b7,ffffffff823b74a3) at __assert+0x2b sys/kern/subr_prf.c:162
pf_frent_remove(fffffd806b658e80,fffffd806b659f50) at pf_frent_remove+0x2a4 sys/net/pf_norm.c:460
pf_fillup_fragment(ffff80002129cc98,0,fffffd806b659f00,ffff80002129cede) at pf_fillup_fragment+0xbeb sys/net/pf_norm.c:679
pf_reassemble(ffff80002129ce10,1,ffff80002129cede) at pf_reassemble+0xeb sys/net/pf_norm.c:781
pf_normalize_ip(ffff80002129cdd0,ffff80002129cede) at pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
pf_test(2,1,ffff800000ae3000,ffff80002129cfe8) at pf_test+0x397
ip_input_if(ffff80002129cfe8,ffff80002129cff4,4,0,ffff800000ae3000) at ip_input_if+0x578 sys/netinet/ip_input.c:338
ipv4_input(ffff800000ae3000,fffffd806d720f00) at ipv4_input+0x48 sys/netinet/ip_input.c:237
tun_dev_write(5d00,ffff80002129d2d8,11,2) at tun_dev_write+0x204 sys/net/if_tun.c:870
spec_write(ffff80002129d130) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806e4165c8,ffff80002129d2d8,11,fffffd807f7b7c60) at VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
vn_write(fffffd806cd0cbf0,ffff80002129d2d8,0) at vn_write+0x14e sys/kern/vfs_vnops.c:414
end trace frame: 0xffff80002129d2c0, count: 0
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823c5187) at panic+0x15e sys/kern/subr_prf.c:218
__assert(ffffffff82433244,ffffffff82451ec5,1b7,ffffffff823b74a3) at __assert+0x2b sys/kern/subr_prf.c:162
pf_frent_remove(fffffd806b658e80,fffffd806b659f50) at pf_frent_remove+0x2a4 sys/net/pf_norm.c:460
pf_fillup_fragment(ffff80002129cc98,0,fffffd806b659f00,ffff80002129cede) at pf_fillup_fragment+0xbeb sys/net/pf_norm.c:679
pf_reassemble(ffff80002129ce10,1,ffff80002129cede) at pf_reassemble+0xeb sys/net/pf_norm.c:781
pf_normalize_ip(ffff80002129cdd0,ffff80002129cede) at pf_normalize_ip+0x11d sys/net/pf_norm.c:1051
pf_test(2,1,ffff800000ae3000,ffff80002129cfe8) at pf_test+0x397
ip_input_if(ffff80002129cfe8,ffff80002129cff4,4,0,ffff800000ae3000) at ip_input_if+0x578 sys/netinet/ip_input.c:338
ipv4_input(ffff800000ae3000,fffffd806d720f00) at ipv4_input+0x48 sys/netinet/ip_input.c:237
tun_dev_write(5d00,ffff80002129d2d8,11,2) at tun_dev_write+0x204 sys/net/if_tun.c:870
spec_write(ffff80002129d130) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806e4165c8,ffff80002129d2d8,11,fffffd807f7b7c60) at VOP_WRITE+0xc6 sys/kern/vfs_vops.c:274
vn_write(fffffd806cd0cbf0,ffff80002129d2d8,0) at vn_write+0x14e sys/kern/vfs_vnops.c:414
dofilewritev(ffff8000212817a0,f0,ffff80002129d2d8,0,ffff80002129d3c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365
sys_write(ffff8000212817a0,ffff80002129d370,ffff80002129d3c0) at sys_write+0x83 sys/kern/sys_generic.c:285
syscall(ffff80002129d440) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff80002129d440) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffc1860, count: -18
ddb{1}> 

Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-openbsd-multicore 2021/02/20 18:00 openbsd 5c3ce5c2f5d6 053a2b26 .config log report syz assert "frag->fr_firstoff[index] != NULL" failed in pf_norm.c
ci-openbsd-multicore 2021/02/01 09:02 openbsd 697029093832 fc9fd31e .config log report syz assert "frag->fr_firstoff[index] != NULL" failed in pf_norm.c
ci-openbsd-multicore 2021/02/20 17:38 openbsd 5c3ce5c2f5d6 053a2b26 .config log report assert "frag->fr_firstoff[index] != NULL" failed in pf_norm.c
ci-openbsd-multicore 2021/02/01 08:21 openbsd 697029093832 fc9fd31e .config log report assert "frag->fr_firstoff[index] != NULL" failed in pf_norm.c
* Struck through repros no longer work on HEAD.