while parsing the fdt header, the name of the begining node marked by
FDT_BEGIN_NODE that is part of the struct block moves out of the block
that results in heap-overflow.
So this patch checks if the length of name (maxlen) + the offset of
the struct block exceeds the size of the whole block.
Signed-off-by: Abdelrahman Youssef <abdelrahmanyossef12@xxxxxxxxx>
---
drivers/of/fdt.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 2c3ea31394..7dc8ee2529 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -210,6 +210,11 @@ static struct device_node *__of_unflatten_dtb(const void *infdt, int size,
maxlen = (unsigned long)fdt + f.off_dt_struct +
f.size_dt_struct - (unsigned long)name;
+ if (maxlen + f.off_dt_struct > f.size_dt_struct) {
+ ret = -ESPIPE;
+ goto err;
+ }
+
len = strnlen(name, maxlen + 1);
if (len > maxlen) {
ret = -ESPIPE;
--
2.43.0
