[U-Boot] [PATCHv2] fdt_support: Fix buffer overflow in fdt_fixup_memory_banks

[Kyle Moffett]

When fdt_fixup_memory_banks is called with 2-cell address and size
fields in the device-tree (IE: 64-bit address and size), then it will
overflow its on-stack "tmp" buffer.

This fixes the buffer size and adds a comment explaining how many bytes
need to be allocated per record.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett at boeing.com>
Cc: Jerry Van Baren <vanbaren at cideas.com>
---
Changelog:
  v2: Resubmitted separately from the other HWW-1U-1A changes.

 common/fdt_support.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/common/fdt_support.c b/common/fdt_support.c
index 6c98e5b..edcf04a 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -394,7 +394,7 @@ int fdt_fixup_memory_banks(void *blob, u64 start[], u64 size[], int banks)
 {
 	int err, nodeoffset;
 	int addr_cell_len, size_cell_len, len;
-	u8 tmp[banks * 8];
+	u8 tmp[banks * 16]; /* Up to 64-bit address + 64-bit size */
 	int bank;
 
 	err = fdt_check_header(blob);
-- 
1.7.2.3