| Message ID | 20210927112205.301876-9-vladimir.oltean@nxp.com |
|---|---|
| State | Accepted |
| Commit | f848b4804e99bbbeaa46934589d77a2403108e66 |
| Delegated to: | Ramon Fried |
| Headers | show |
| Series | Fix some non-NULL terminated strings in the networking subsystem | expand |
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/fsl_enetc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/fsl_enetc.c b/drivers/net/fsl_enetc.c > index 566cdc7e546a..b7e2c1f0880c 100644 > --- a/drivers/net/fsl_enetc.c > +++ b/drivers/net/fsl_enetc.c > @@ -270,7 +270,7 @@ static void enetc_start_pcs(struct udevice *dev) > priv->imdio.read = enetc_mdio_read; > priv->imdio.write = enetc_mdio_write; > priv->imdio.priv = priv->port_regs + ENETC_PM_IMDIO_BASE; > - strncpy(priv->imdio.name, dev->name, MDIO_NAME_LEN); > + strlcpy(priv->imdio.name, dev->name, MDIO_NAME_LEN); > if (!miiphy_get_dev_by_name(priv->imdio.name)) > mdio_register(&priv->imdio); > } > -- > 2.25.1 > Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
diff --git a/drivers/net/fsl_enetc.c b/drivers/net/fsl_enetc.c index 566cdc7e546a..b7e2c1f0880c 100644 --- a/drivers/net/fsl_enetc.c +++ b/drivers/net/fsl_enetc.c @@ -270,7 +270,7 @@ static void enetc_start_pcs(struct udevice *dev) priv->imdio.read = enetc_mdio_read; priv->imdio.write = enetc_mdio_write; priv->imdio.priv = priv->port_regs + ENETC_PM_IMDIO_BASE; - strncpy(priv->imdio.name, dev->name, MDIO_NAME_LEN); + strlcpy(priv->imdio.name, dev->name, MDIO_NAME_LEN); if (!miiphy_get_dev_by_name(priv->imdio.name)) mdio_register(&priv->imdio); }
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/fsl_enetc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)