Messages in this thread | | | Date | Mon, 1 Aug 2005 20:45:29 -0700 (PDT) | From | Linus Torvalds <> | Subject | Re: [patch 2.6.13-rc4] fix get_user_pages bug |
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On Tue, 2 Aug 2005, Nick Piggin wrote: > > Surely this introduces integrity problems when `force` is not set?
"force" changes how we test the vma->vm_flags, that was always the meaning from a security standpoint (and that hasn't changed).
The old code had this "lookup_write = write && !force;" thing because there it used "force" to _clear_ the write bit test, and that was what caused the race in the first place - next time around we would accept a non-writable page, even if it hadn't actually gotten COW'ed.
So no, the patch doesn't introduce integrity problems by ignoring "force". Quite the reverse - it _removes_ the integrity problems by ignoring it there. That's kind of the whole point.
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