5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
[ Upstream commit a9515ff4fb142b690a0d2b58782b15903b990dba ]
When of_overlay_fdt_apply() fails, the changeset may be partially
applied, and the caller is still expected to call of_overlay_remove() to
clean up this partial state.
However, of_overlay_apply() calls of_resolve_phandles() before
init_overlay_changeset(). Hence if the overlay fails to apply due to an
unresolved symbol, the overlay_changeset.cset.entries list is still
uninitialized, and cleanup will crash with a NULL-pointer dereference in
overlay_removal_is_ok().
Fix this by moving the call to of_changeset_init() from
init_overlay_changeset() to of_overlay_fdt_apply(), where all other
early initialization is done.
Fixes: f948d6d8b792bb90 ("of: overlay: avoid race condition between applying multiple overlays")
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Link: https://lore.kernel.org/r/4f1d6d74b61cba2599026adb6d1948ae559ce91f.1690533838.git.geert+renesas@xxxxxxxxx
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/of/overlay.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
index 8f2ddba3947e5..ee7f3659b353c 100644
--- a/drivers/of/overlay.c
+++ b/drivers/of/overlay.c
@@ -752,8 +752,6 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs)
if (!of_node_is_root(ovcs->overlay_root))
pr_debug("%s() ovcs->overlay_root is not root\n", __func__);
- of_changeset_init(&ovcs->cset);
-
cnt = 0;
/* fragment nodes */
@@ -995,6 +993,7 @@ int of_overlay_fdt_apply(const void *overlay_fdt, u32 overlay_fdt_size,
INIT_LIST_HEAD(&ovcs->ovcs_list);
list_add_tail(&ovcs->ovcs_list, &ovcs_list);
+ of_changeset_init(&ovcs->cset);
/*
* Must create permanent copy of FDT because of_fdt_unflatten_tree()
--
2.40.1
