4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ma Ke <make24@xxxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Fixes: c9b37458e956 ("USB2NET : SR9700 : One chip USB 1.1 USB2NET SR9700Device Driver Support")
Signed-off-by: Ma Ke <make24@xxxxxxxxxxx>
Reviewed-by: Shigeru Yoshida <syoshida@xxxxxxxxxx>
Reviewed-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
