Re: [PATCH 0/2] of: phandle_cache, fix refcounts, remove stale entry

From: Frank Rowand
Date: Fri Dec 14 2018 - 01:46:41 EST


Hi Michael Bringmann,

On 12/13/18 10:42 PM, frowand.list@xxxxxxxxx wrote:
> From: Frank Rowand <frank.rowand@xxxxxxxx>
>
> Non-overlay dynamic devicetree node removal may leave the node in
> the phandle cache. Subsequent calls to of_find_node_by_phandle()
> will incorrectly find the stale entry. This bug exposed the foloowing
> phandle cache refcount bug.
>
> The refcount of phandle_cache entries is not incremented while in
> the cache, allowing use after free error after kfree() of the
> cached entry.
>
> Frank Rowand (2):
> of: of_node_get()/of_node_put() nodes held in phandle cache
> of: __of_detach_node() - remove node from phandle cache
>
> drivers/of/base.c | 99 ++++++++++++++++++++++++++++++++++++-------------
> drivers/of/dynamic.c | 3 ++
> drivers/of/of_private.h | 4 ++
> 3 files changed, 81 insertions(+), 25 deletions(-)
>

Can you please test that these patches fix the problem that you
reported in:

[PATCH v03] powerpc/mobility: Fix node detach/rename problem

Thanks,

Frank