From mboxrd@z Thu Jan 1 00:00:00 1970 From: frowand.list@gmail.com Subject: [PATCH 0/2] of: phandle_cache, fix refcounts, remove stale entry Date: Thu, 13 Dec 2018 22:42:49 -0800 Message-ID: <1544769771-5468-1-git-send-email-frowand.list@gmail.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: robh+dt@kernel.org, Michael Bringmann , linuxppc-dev@lists.ozlabs.org Cc: Michael Ellerman , Tyrel Datwyler , Thomas Falcon , Juliet Kim , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org From: Frank Rowand 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(-) -- Frank Rowand