tree f0f5053b44b53fea4065bd05aeb9f0a53090d9dd
parent 912f9ee21c836081e3c96dfe61025841ebeb95da
author Anton Blanchard <anton@samba.org> 1235267405 +0000
committer Benjamin Herrenschmidt <benh@kernel.crashing.org> 1235364801 +1100

powerpc: Ensure random space between stack and mmaps

get_random_int() returns the same value within a 1 jiffy interval. This means
that the mmap and stack regions will almost always end up the same distance
apart, making a relative offset based attack possible.

To fix this, shift the randomness we use for the mmap region by 1 bit.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>