From: Slawomir Stepien <slawomir.stepien@xxxxxxxxx>
Before this change, the memory pointed by fields 'overlay_tree' and
'fdt' will be double freed by a call to free_overlay_changeset() from
of_overlay_apply(), when the init_overlay_changeset() fails.
The first free will happen under 'err_free_tree' label and for the
second time under 'err_free_overlay_changeset' label, where we call
free_overlay_changeset().
This could happen for example, when you are applying an overlay to a
target path that does not exists.
By setting the pointers only when we are sure that
init_overlay_changeset() will not fail, will prevent this double free.
Signed-off-by: Slawomir Stepien <slawomir.stepien@xxxxxxxxx>
---
drivers/of/overlay.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index d80160cf34bb..a72a9a415f8f 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -750,9 +750,6 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
if (!of_node_is_root(tree))
pr_debug("%s() tree is not root\n", __func__);
- ovcs->overlay_tree = tree;
- ovcs->fdt = fdt;
-
INIT_LIST_HEAD(&ovcs->ovcs_list);
of_changeset_init(&ovcs->cset);
@@ -829,6 +826,8 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs,
goto err_free_fragments;
}
+ ovcs->overlay_tree = tree;
+ ovcs->fdt = fdt;
ovcs->id = id;
ovcs->count = cnt;
ovcs->fragments = fragments;
--
Slawomir Stepien
