"Strong" stack protection for GCC [LWN.net]

"Strong" stack protection for GCC

Posted Feb 16, 2014 11:06 UTC (Sun) by mchapman (subscriber, #66589)
In reply to: "Strong" stack protection for GCC by paulj
Parent article: "Strong" stack protection for GCC

> Though, a trivial test-case (adding command-line arguments) doesn't behave any differently with overflow when compiled with ftrapv on x86-64 and happily runs past an overflow

It needs to be a 64-bit signed integer. An int is likely to be only 32 bits.

"Strong" stack protection for GCC

Posted Feb 16, 2014 11:13 UTC (Sun) by paulj (subscriber, #341) [Link] (1 responses)

Ah. Indeed, with longs instead and a 64bit overflow it core-dumps.

Hmm, that's pretty limited in usefulness so, and buggy with respect to what the documentation suggests it does (the docs don't qualify when overflow checks will actually be done). :(

"Strong" stack protection for GCC

Posted Feb 16, 2014 11:15 UTC (Sun) by mchapman (subscriber, #66589) [Link]

> and buggy with respect to what the documentation suggests it does

Yes, indeed: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52478