Messages in this thread | | | Subject | Re: [PATCH V2] slub: avoid potential NULL dereference or corruption | From | Pekka Enberg <> | Date | Wed, 23 Nov 2011 23:19:51 +0200 |
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On Wed, 2011-11-23 at 09:17 -0600, Christoph Lameter wrote: > On Wed, 23 Nov 2011, Pekka Enberg wrote: > > > On Tue, 22 Nov 2011, Eric Dumazet wrote: > > > show_slab_objects() can trigger NULL dereferences or memory corruption. > > > > > > Another cpu can change its c->page to NULL or c->node to NUMA_NO_NODE > > > while we use them. > > > > > > Use ACCESS_ONCE(c->page) and ACCESS_ONCE(c->node) to make sure this > > > cannot happen. > > > > > > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> > > > > Did someone test this patch? Does it fix any of the reported issues? > > It does not fix any current issues but it is safe against potential > compiler refetching of variables that we have already checked against > bad values. > > I thought I acked it already?
Yes, you did. I'm just trying to figure out which ones are going straight to Linus and which ones can wait for v3.3.
Pekka
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