From 2f945a792f67815abca26fa8a5e863ccf3fa1181 Mon Sep 17 00:00:00 2001
From: Sergey Shtylyov <s.shtylyov@omp.ru>
Date: Sat, 13 Aug 2022 23:34:16 +0300
Subject: [PATCH] of: fdt: fix off-by-one error in unflatten_dt_nodes()
Git-commit: 2f945a792f67815abca26fa8a5e863ccf3fa1181
Patch-mainline: v6.0-rc6
References: git-fixes
Commit 78c44d910d3e ("drivers/of: Fix depth when unflattening devicetree")
forgot to fix up the depth check in the loop body in unflatten_dt_nodes()
which makes it possible to overflow the nps[] buffer...
Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.
Fixes: 78c44d910d3e ("drivers/of: Fix depth when unflattening devicetree")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/7c354554-006f-6b31-c195-cdfe4caee392@omp.ru
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/of/fdt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 7bc92923104c..1c573e7a60bc 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -314,7 +314,7 @@ static int unflatten_dt_nodes(const void *blob,
for (offset = 0;
offset >= 0 && depth >= initial_depth;
offset = fdt_next_node(blob, offset, &depth)) {
- if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
+ if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1))
continue;
if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
--
2.35.3