GPLv2 gives an implicit grant. You cannot distribute your code under GPLv2 unless you can ensure the user has full right to use and redistribute your code.

Section 6 says "You may not impose any further restrictions on the recipients' exercise of the rights granted herein."

Section 7 says "if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program."

The scope may be different under different laws (that's one of the reasons GPLv3 makes it explicit) but it's pretty much reasonable to assume Oracle would rather not test it on court.