Re: [PATCH] module: Harden STRICT_MODULE_RWX

From: Jessica Yu
Date: Fri Apr 10 2020 - 05:04:15 EST


+++ Miroslav Benes [09/04/20 18:55 +0200]:
I am still wondering if there are modules out there with sections flags
combination which would cause the same problem with layout_sections() and
move_module() logic I described earlier. But that it is a separate issue.

And of course I misread the condition in layout_sections() and all should
be fine. Oh well...

Me too :-( For some reason I misread it as an exact mask match, ugh.
In any case, it looks like we are fine since we'd catch all SHF_ALLOC
sections at the minimum and they would have sh_entsize set, and we
appropriately ignore non-SHF_ALLOC sections in move_module(), so
the hypothetical problem I described earlier was incorrect.