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vmsplice(): the making of a local root exploit

vmsplice(): the making of a local root exploit

Posted Feb 12, 2008 0:48 UTC (Tue) by jwb (guest, #15467)
Parent article: vmsplice(): the making of a local root exploit

Can anyone explain why the fix only applied to len and not off?  Is it because the base
address does not come from userspace?


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vmsplice(): the making of a local root exploit

Posted Feb 12, 2008 9:11 UTC (Tue) by and (subscriber, #2883) [Link]

If my understanding of this is correct, then off is the offset within the 
first page (i.e. off is always smaller than PAGE_SIZE).

vmsplice(): the making of a local root exploit

Posted Feb 12, 2008 22:48 UTC (Tue) by jd (guest, #26381) [Link]

If it's just casting, then fixing an unexploitable casting bug is tidier than leaving it,
explicitly states intention, and prevents these souped-up aggressive optimizing compilers used
on the kernel from optimizing in a problem sometime down the road. On the other hand,
unnecessary changes introduce risks of adding as many problems as they fix.

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