Messages in this thread | | | Subject | Re: BUG: bad usercopy in memdup_user | From | Randy Dunlap <> | Date | Tue, 19 Dec 2017 14:09:45 -0800 |
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On 12/19/2017 01:48 PM, Al Viro wrote: > On Tue, Dec 19, 2017 at 01:36:46PM -0800, Linus Torvalds wrote: > >> I suspect that an "offset and size within the kernel object" value >> might make sense. But what does the _pointer_ tell you? > > Well, for example seeing a 0xfffffffffffffff4 where a pointer to object > must have been is a pretty strong hint to start looking for a way for > that ERR_PTR(-ENOMEM) having ended up there... Something like > 0x6e69622f7273752f is almost certainly a misplaced "/usr/bin", i.e. a
possibly poison values also?
> pathname overwriting whatever it ends up in, etc. And yes, I have run > into both of those in real life. > > Debugging the situation when crap value has ended up in place of a > pointer is certainly a case where you do want to see what exactly has > ended up in there...
-- ~Randy
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