From: Subash Abhinov Kasiviswanathan subashab@codeaurora.org
[ Upstream commit 2abb5792387eb188b12051337d5dcd2cba615cb0 ]
This allows the changelink operation to succeed if the mux_id was specified as an argument. Note that the mux_id must match the existing mux_id of the rmnet device or should be an unused mux_id.
Fixes: 1dc49e9d164c ("net: rmnet: do not allow to change mux id if mux id is duplicated") Reported-and-tested-by: Alex Elder elder@linaro.org Signed-off-by: Sean Tranchetti stranche@codeaurora.org Signed-off-by: Subash Abhinov Kasiviswanathan subashab@codeaurora.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../ethernet/qualcomm/rmnet/rmnet_config.c | 31 ++++++++++++------- 1 file changed, 19 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c index 37786affa9750..7389648d0feaf 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c @@ -288,7 +288,6 @@ static int rmnet_changelink(struct net_device *dev, struct nlattr *tb[], { struct rmnet_priv *priv = netdev_priv(dev); struct net_device *real_dev; - struct rmnet_endpoint *ep; struct rmnet_port *port; u16 mux_id;
@@ -303,19 +302,27 @@ static int rmnet_changelink(struct net_device *dev, struct nlattr *tb[],
if (data[IFLA_RMNET_MUX_ID]) { mux_id = nla_get_u16(data[IFLA_RMNET_MUX_ID]); - if (rmnet_get_endpoint(port, mux_id)) { - NL_SET_ERR_MSG_MOD(extack, "MUX ID already exists"); - return -EINVAL; - } - ep = rmnet_get_endpoint(port, priv->mux_id); - if (!ep) - return -ENODEV;
- hlist_del_init_rcu(&ep->hlnode); - hlist_add_head_rcu(&ep->hlnode, &port->muxed_ep[mux_id]); + if (mux_id != priv->mux_id) { + struct rmnet_endpoint *ep; + + ep = rmnet_get_endpoint(port, priv->mux_id); + if (!ep) + return -ENODEV;
- ep->mux_id = mux_id; - priv->mux_id = mux_id; + if (rmnet_get_endpoint(port, mux_id)) { + NL_SET_ERR_MSG_MOD(extack, + "MUX ID already exists"); + return -EINVAL; + } + + hlist_del_init_rcu(&ep->hlnode); + hlist_add_head_rcu(&ep->hlnode, + &port->muxed_ep[mux_id]); + + ep->mux_id = mux_id; + priv->mux_id = mux_id; + } }
if (data[IFLA_RMNET_FLAGS]) {