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| author | Ma Ke <make24@iscas.ac.cn> | 2024-07-25 10:29:42 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-07-26 11:14:41 +0100 |
| commit | 08f3a5c38087d1569e982a121aad1e6acbf145ce (patch) | |
| tree | 50ede35f80ad22aeedcacdbfa5e3297558a8c824 /drivers/net/usb/sr9700.c | |
| parent | 07c10cff663e54dadff7cfb6cf09e266456ed073 (diff) | |
| download | lwn-08f3a5c38087d1569e982a121aad1e6acbf145ce.tar.gz lwn-08f3a5c38087d1569e982a121aad1e6acbf145ce.zip | |
net: usb: sr9700: fix uninitialized variable use in sr_mdio_read
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>
Diffstat (limited to 'drivers/net/usb/sr9700.c')
| -rw-r--r-- | drivers/net/usb/sr9700.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/net/usb/sr9700.c b/drivers/net/usb/sr9700.c index 0a662e42ed96..cb7d2f798fb4 100644 --- a/drivers/net/usb/sr9700.c +++ b/drivers/net/usb/sr9700.c @@ -179,6 +179,7 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc) struct usbnet *dev = netdev_priv(netdev); __le16 res; int rc = 0; + int err; if (phy_id) { netdev_dbg(netdev, "Only internal phy supported\n"); @@ -189,11 +190,17 @@ static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc) 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 |