Description:
In libre office calc, under certain conditions (see "steps to reproduce section"), editing a formula and copy-pasting a part of its definition causes LibreOffice to freeze but also (more troublesome) endless allocation of memory until no free RAM remains and the OS as a whole freezes.

Tested on linux mint 18.1 Serena, with the default & up-to-date LibreOffice version of this distribution.


Steps to Reproduce:
1. Open libreoffice calc

2. Insert formula (Insert > Object > Formula)

3. Copy-paste the following formula:

{1}over{h^3}
left[
matrix{ c_1 # c_4 # 0 # -c_4 # -c_1 ##
        c_2 # c_5 # 0 # -c_5 # -c_2 ##
        c_3 # c_6 # 0 # -c_6 # -c_3 } 
right]

4. place your cursor before "c_1" i.e. "matrix{ |c_1" where "|" represents cursor
5. press shift + downArrow : you are selecting a line
6. Ctrl + C : you are copying this line
7. Place cursor before closing brace i.e. "-c_3 |}" where "|" represents cursor
8. Hit Ctrl + V




Actual Results:  
At that point LO freezes. I have the "System monitor" applet for Mate and I can see the used RAM value increasing linearly in time until there is no more free RAM and the OS as a whole freezes.

Expected Results:
Simple paste, with LO not freezing and not allocating crazy amounts of memory.


Reproducible: Always

User Profile Reset: No

Additional Info:


User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:54.0) Gecko/20100101 Firefox/54.0