4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ma Ke make24@iscas.ac.cn
commit 08f3a5c38087d1569e982a121aad1e6acbf145ce upstream.
It could lead to error happen because the variable res is not updated if the call to sr_share_read_word returns an error. In this particular case error code was returned and res stayed uninitialized. Same issue also applies to sr_read_reg.
This can be avoided by checking the return value of sr_share_read_word and sr_read_reg, and propagating the error if the read operation failed.
Found by code review.
Cc: stable@vger.kernel.org Fixes: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support") Signed-off-by: Ma Ke make24@iscas.ac.cn Reviewed-by: Shigeru Yoshida syoshida@redhat.com Reviewed-by: Hariprasad Kelam hkelam@marvell.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/usb/sr9700.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -178,6 +178,7 @@ static int sr_mdio_read(struct net_devic struct usbnet *dev = netdev_priv(netdev); __le16 res; int rc = 0; + int err;
if (phy_id) { netdev_dbg(netdev, "Only internal phy supported\n"); @@ -188,11 +189,17 @@ static int sr_mdio_read(struct net_devic if (loc == MII_BMSR) { u8 value;
- sr_read_reg(dev, SR_NSR, &value); + err = sr_read_reg(dev, SR_NSR, &value); + if (err < 0) + return err; + if (value & NSR_LINKST) rc = 1; } - sr_share_read_word(dev, 1, loc, &res); + err = sr_share_read_word(dev, 1, loc, &res); + if (err < 0) + return err; + if (rc == 1) res = le16_to_cpu(res) | BMSR_LSTATUS; else