Getting a file to Samsung Galaxy Tab from my Laptop without Android? I am trying to install new Android OS to Samsung Galaxy Tab but it does not have a Memory-card -slot and it does not have any OS currently. I need to somehow get the OS -file to the Samsung Galaxy Tab from my laptop, how can I do it?

ttyACM3 -description with ls

# ls -al /dev/ttyACM3 
crw-rw---- 1 root dialout 166, 3 Oct 27 14:06 /dev/ttyACM3


Dmesg

 [538846.011011] wlan0: no IPv6 routers present
[539228.371156] usb 2-1.2: new high-speed USB device number 67 using ehci_hcd
[539228.387241] hub 2-1:1.0: unable to enumerate USB device on port 2
[539228.882058] usb 2-1.2: new high-speed USB device number 68 using ehci_hcd
[539228.990676] usb 2-1.2: New USB device found, idVendor=04e8, idProduct=6860
[539228.990685] usb 2-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[539228.990691] usb 2-1.2: Product: SAMSUNG_Android
[539228.990696] usb 2-1.2: Manufacturer: SAMSUNG
[539228.990700] usb 2-1.2: SerialNumber: 4xxxxxxxxxxxxxxxx
[539228.995453] cdc_acm 2-1.2:1.0: This device cannot do calls on its own. It is not a modem.
[539228.995729] cdc_acm 2-1.2:1.0: ttyACM3: USB ACM device
[539820.734285] thinkpad_acpi: unknown possible thermal alarm or keyboard event received
[539820.734288] thinkpad_acpi: unhandled HKEY event 0x6040
[539820.734290] thinkpad_acpi: please report the conditions when this event happened to ibm-acpi-devel@lists.sourceforge.net
[539820.734655] thinkpad_acpi: EC reports that Thermal Table has changed


usb-devices

:  Bus=02 Lev=02 Prnt=02 Port=01 Cnt=01 Dev#= 69 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=04e8 ProdID=6860 Rev=04.00
S:  Manufacturer=SAMSUNG
S:  Product=SAMSUNG_Android
S:  SerialNumber=4xxxxxxxxxxxxxxx
C:  #Ifs= 3 Cfg#= 1 Atr=c0 MxPwr=96mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=02 Prot=01 Driver=cdc_acm
I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_acm
I:  If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none)


I can see that my laptop can detect the SGT but I am now trying to find where it is mounted to. How can I find the directory for SGT to save a file to it?
As I said in my comment, you should be able to flash using Odin. I'm not sure it works through a VM though, so perhaps you might have better luck with Heimdall.

Basically, you need to get the appropriate firmware for your device from here (signup required). Then, shut down your device and boot it while holding volume down + power. Once the tablet enters download mode, connect it to a PC. 

If using Odin, the file you downloaded goes into the PDA box. I'm not too sure about Heimdall, but it looks like the downloaded file goes into the "Heimdall firmware package" box. Then click "Start" in Odin and wait for your device to reboot. 

At this point, the tablet should boot into Android.