| Message ID | 20210927112205.301876-3-vladimir.oltean@nxp.com |
|---|---|
| State | Accepted |
| Commit | 61efbece570af3fe0881fc59dba06ede15eb8a6f |
| 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> > --- > 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 > Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
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;
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> --- board/gdsys/a38x/ihs_phys.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)