"Strong" stack protection for GCC

"Strong" stack protection for GCC

jimparis above gave a couple excellent examples, but how about another?

void vulnerable( char *too_big )
{
    char too_small[8];

    // ...
    strcpy( too_small, too_big );
    // ...
}

On a machine whose stack grows up instead of down (Alpha was one such architecture), strcpy() could end up smashing its own return address due to a buffer overflow in its caller. A canary in vulnerable() won't help.

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