On Mon, Sep 27, 2021 at 2:22 PM Vladimir Oltean vladimir.oltean@nxp.com wrote:
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@nxp.com
drivers/net/macb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 57ea45e2dc7f..8151104acfc0 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -1245,7 +1245,7 @@ int macb_eth_initialize(int id, void *regs, unsigned int phy_addr) struct mii_dev *mdiodev = mdio_alloc(); if (!mdiodev) return -ENOMEM;
strncpy(mdiodev->name, netdev->name, MDIO_NAME_LEN);
strlcpy(mdiodev->name, netdev->name, MDIO_NAME_LEN); mdiodev->read = macb_miiphy_read; mdiodev->write = macb_miiphy_write;@@ -1403,7 +1403,7 @@ static int macb_eth_probe(struct udevice *dev) macb->bus = mdio_alloc(); if (!macb->bus) return -ENOMEM;
strncpy(macb->bus->name, dev->name, MDIO_NAME_LEN);
strlcpy(macb->bus->name, dev->name, MDIO_NAME_LEN); macb->bus->read = macb_miiphy_read; macb->bus->write = macb_miiphy_write;-- 2.25.1
Reviewed-by: Ramon Fried rfried.dev@gmail.com