path: root/drivers/of/dynamic.c
diff options
authorFrank Rowand <frank.rowand@sony.com>2018-12-18 11:40:03 -0800
committerRob Herring <robh@kernel.org>2018-12-21 12:42:36 -0600
commit5801169a2ed20003f771acecf3ac00574cf10a38 (patch)
tree56bcdc99f2d669033eea3c4308e52419a44ddc7e /drivers/of/dynamic.c
parentb8a9ac1a5b99a2fcbed19fd29d2d59270c281a31 (diff)
of: __of_detach_node() - remove node from phandle cache
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. Remove the node from the cache. Add paranoia checks in of_find_node_by_phandle() as a second level of defense (do not return cached node if detached, do not add node to cache if detached). Fixes: 0b3ce78e90fc ("of: cache phandle nodes to reduce cost of of_find_node_by_phandle()") Reported-by: Michael Bringmann <mwb@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'drivers/of/dynamic.c')
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index b4e5b90cb314..a09c1c3cf831 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -277,6 +277,9 @@ void __of_detach_node(struct device_node *np)
of_node_set_flag(np, OF_DETACHED);
+ /* race with of_find_node_by_phandle() prevented by devtree_lock */
+ __of_free_phandle_cache_entry(np->phandle);