Messages in this thread | | | Date | Mon, 11 Apr 2011 12:45:02 -0500 | From | Rob Landley <> | Subject | Re: [PATCH 3/3] Compare namespaces when comparing addresses in auth_unix cache. |
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On 04/11/2011 08:57 AM, Alexey Dobriyan wrote: > On Mon, Apr 11, 2011 at 4:36 PM, Serge E. Hallyn <serge@hallyn.com> wrote: > >> Besides use-after-free, the other concern is an invalid net_eq() >> result due to the * being re-used for a new netns. > > Exactly. > > "struct net" dies last, no exceptions, anything different is a disaster.
Actually the patch turns out to be irrelevant because Pavel made the whole thing into a pernet subsystem, so it was already fixed in a different way. (Commit 2f72c9b7. My bad, I initially started working against an NFS tree with an older kernel version, this fix was to a different source file so my patch still applied, and I just regression tested that it worked, not that it still failed without it. Just caught it now.)
I actually did talk about addressing potential reuse of the net * in my email with Stanislav (point of the patch was to allow one cache to maintain two different contexts at the same time; a situation that changed the meaning of an existing cache entry by requiring the old context to go away didn't introduce any new problems that a single context didn't already have due to DNAT, servers moving, administrators changing credentials on the server). But sort of a moot point now.
I believe the third patch can be dropped entirely.
Rob
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