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Subject[PATCH 0/9] Series to make copy_from_user to a stack slot provable right
[PATCH 0/9] Series to make copy_from_user to a stack slot provable right

This series contains a series of patches that, when applied, make every
copy_from_user() in a make allyesconfig to a (direct) stack slot
provable-by-gcc to have a correct size.

This is useful because if we fix all of these, we can make the non-provable
case an error, as an indication of a possible security hole.

Now the series has 4 types of patches
1) changes where the original code really was missing checks
2) changes where the checks were coded so complex and games were played with
types, that I (and the compiler) couldn't be sure if it was correct or
3) changes where we're hitting a small gcc missing optimization, but where
a simplification of the code allows gcc to prove things anyway.
( is filed for this)
4) a case in sys_socketcall where Dave Miller and co were very smart in
optimizing the code to the point where it's not reasonable for gcc
to realize the result is ok.

Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,

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