[PATCH 02/25] board: gdsys: a38x: ensure mdiodev->name is NULL terminated after MDIO_NAME_LEN truncation

Vladimir Oltean vladimir.oltean at nxp.com
Mon Sep 27 13:21:42 CEST 2021


strncpy() simply bails out when copying a source string whose size
exceeds the destination string size, potentially leaving the destination
string unterminated.

One possible way to address is to pass MDIO_NAME_LEN - 1 and a
previously zero-initialized destination string, but this is more
difficult to maintain.

The chosen alternative is to use strlcpy(), which properly limits the
copy len in the (srclen >= size) case to "size - 1", and which is also
more efficient than the strncpy() byte-by-byte implementation by using
memcpy. The destination string returned by strlcpy() is always NULL
terminated.

Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
---
 board/gdsys/a38x/ihs_phys.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/board/gdsys/a38x/ihs_phys.c b/board/gdsys/a38x/ihs_phys.c
index c23d15092144..e09c0006b76f 100644
--- a/board/gdsys/a38x/ihs_phys.c
+++ b/board/gdsys/a38x/ihs_phys.c
@@ -110,9 +110,7 @@ int register_miiphy_bus(uint k, struct mii_dev **bus)
 
 	if (!mdiodev)
 		return -ENOMEM;
-	strncpy(mdiodev->name,
-		name,
-		MDIO_NAME_LEN);
+	strlcpy(mdiodev->name, name, MDIO_NAME_LEN);
 	mdiodev->read = bb_miiphy_read;
 	mdiodev->write = bb_miiphy_write;
 
-- 
2.25.1



More information about the U-Boot mailing list