Problem with OpenBSD 2.8 system

[George Morgan <gemorga2_(_at_)_vt_(_dot_)_edu>]

Using OpenBSD 2.8 (i386) on a Cyrix 6x86-120 with dual ethernet 
interfaces as a firewall I have recently started getting the 
following messages:

Apr  2 21:29:17 dragon /bsd: Data modified on freelist: word 3 of 
object 0xe0620ec0 size 64 previous type UVM amap (0xdeadbeee != 
0xdeadbeef)

Does this indicate a hardware (RAM) problem?  Malicious code (have I 
been hacked?) This machine only has 16 MB of ram so I assume this 
could be related to swap and disk problems also, but I don't know.  
DMESG follows (some info removed or **'d out):

OpenBSD 2.8-stable (DRAGON1) #1: Wed Jan 17 02:38:26 EST 2001

cpu0: xchg bug workaround performed
cpu0: Cyrix 6x86 (486-class)
real mem  = 16363520 (15980K)
avail mem = 12685312 (12388K)
using 225 buffers containing 921600 bytes (900K) of memory
mainbus0 (root)
bios0 at mainbus0: AT/286+(b6) BIOS, date 11/13/98, BIOS32 rev. 0 @ 
0xfb4c0
apm0 at bios0: Power Management spec V1.2
apm0: AC on, battery charge unknown
pcibios0 at bios0: rev. 2.1 found at 0xf0000[0xb938]
pcibios0: PCI IRQ Routing Table rev. 1.0 found at 0xfddf0, size 128 
bytes (6 entries)
pcibios0: PCI Interrupt Router at 000:07:0 ("Intel 82371SB (Triton 
II) PCI-ISA" rev 0x00)
pcibios0: PCI Exclusive IRQs: 10 11
pcibios0: PCI bus #0 is the last bus
pci0 at mainbus0 bus 0: configuration mode 1 (bios)
pchb0 at pci0 dev 0 function 0 "Intel 82439TX System (MTXC)" rev 0x01
pcib0 at pci0 dev 7 function 0 "Intel 82371AB PIIX4 ISA" rev 0x01
pciide0 at pci0 dev 7 function 1 "Intel 82371AB IDE (PIIX4)" rev 
0x01: DMA, channel 0 wired to compatibility, channel 1 wired to 
compatibility
wd0 at pciide0 channel 0 drive 0: <ST36531A>
wd0: can use 32-bit, PIO mode 4, DMA mode 2, Ultra-DMA mode 2
wd0: 32-sector PIO, LBA, 6204MB, 13446 cyl, 15 head, 63 sec, 12706470 
sectors
pciide0: channel 0 interrupting at irq 14
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 2 (using DMA data 
transfers)
atapiscsi0 at pciide0 channel 1
scsibus0 at atapiscsi0: 2 targets
cd0 at scsibus0 targ 0 lun 0: <BCD, E520C, 0.35> SCSI0 5/cdrom 
removable
cd0: can use 32-bit, PIO mode 4, DMA mode 2, Ultra-DMA mode 2
pciide0: channel 1 interrupting at irq 15
cd0(pciide0:1:0): using PIO mode 4, Ultra-DMA mode 2 (using DMA data 
transfers)
"Intel 82371AB USB (PIIX4)" rev 0x01 at pci0 dev 7 function 2 not 
configured
"Intel 82371AB Power Management (PIIX4)" rev 0x01 at pci0 dev 7 
function 3 not configured
de0 at pci0 dev 15 function 0 "DEC DECchip 21140 (FasterNet)" rev 
0x22: irq 10
de0: 21140A [10-100Mb/s] pass 2.2 address **:**:**:**:**:**
isa0 at pcib0
isadma0 at isa0
ne0 at isa0 port 0x240/32 irq 9
ne0: NE2000 Ethernet
ne0: address **:**:**:**:**:**
pcppi0 at isa0 port 0x61
sysbeep0 at pcppi0
lpt0 at isa0 port 0x378/4 irq 7
npx0 at isa0 port 0xf0/16: using exception 16
pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo
vt0 at isa0 port 0x60/16 irq 1: vga 80 col, color, 8 scr, mf2-kbd
pms0 at vt0 irq 12
fdc0 at isa0 port 0x3f0/6 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
fd1 at fdc0 drive 1: 1.44MB 80 cyl, 2 head, 18 sec
biomask c040 netmask c640 ttymask d6c2
pctr: no performance counters in CPU
dkcsum: wd0 matched BIOS disk 80
root on wd0a
rootdev=0x0 rrootdev=0x300 rawdev=0x302
de0: enabling Full Duplex 100baseTX port


George Morgan
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