net: ti: icssm-prueth: unwind cleanly in probe()

This error handling triggers a Smatch warning:

    drivers/net/ethernet/ti/icssm/icssm_prueth.c:1574 icssm_prueth_probe()
    warn: 'prueth->pru1' is an error pointer or valid

The warning is harmless because the pru_rproc_put() function has an
IS_ERR_OR_NULL() check built in.  However, there is a small bug if
syscon_regmap_lookup_by_phandle() fails.  In that case we should call
of_node_put() on eth0_node and eth1_node.

It's a little bit easier to re-write this code to only free things which
we know have been allocated successfully.

Fixes: 511f6c1ae093 ("net: ti: icssm-prueth: Adds ICSSM Ethernet driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Parvathi Pudi <parvathi@couthit.com>
Link: https://patch.msgid.link/aMvVagz8aBRxMvFn@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/ti/icssm/icssm_prueth.c b/drivers/net/ethernet/ti/icssm/icssm_prueth.c
index 65d0b792132db6d0937f478fea3f8f5cfd18a324..293b7af04263f843ee83222026910fafb936bf54 100644 (file)
--- a/drivers/net/ethernet/ti/icssm/icssm_prueth.c
+++ b/drivers/net/ethernet/ti/icssm/icssm_prueth.c
@@ -1390,7 +1390,8 @@ static int icssm_prueth_probe(struct platform_device *pdev)
        prueth->mii_rt = syscon_regmap_lookup_by_phandle(np, "ti,mii-rt");
        if (IS_ERR(prueth->mii_rt)) {
                dev_err(dev, "couldn't get mii-rt syscon regmap\n");
-               return -ENODEV;
+               ret = PTR_ERR(prueth->mii_rt);
+               goto put_eth;
        }
 
        if (eth0_node) {
@@ -1398,7 +1399,7 @@ static int icssm_prueth_probe(struct platform_device *pdev)
                if (IS_ERR(prueth->pru0)) {
                        ret = PTR_ERR(prueth->pru0);
                        dev_err_probe(dev, ret, "unable to get PRU0");
-                       goto put_pru;
+                       goto put_eth;
                }
        }
 
@@ -1407,7 +1408,7 @@ static int icssm_prueth_probe(struct platform_device *pdev)
                if (IS_ERR(prueth->pru1)) {
                        ret = PTR_ERR(prueth->pru1);
                        dev_err_probe(dev, ret, "unable to get PRU1");
-                       goto put_pru;
+                       goto put_pru0;
                }
        }
 
@@ -1415,7 +1416,7 @@ static int icssm_prueth_probe(struct platform_device *pdev)
        if (IS_ERR(pruss)) {
                ret = PTR_ERR(pruss);
                dev_err(dev, "unable to get pruss handle\n");
-               goto put_pru;
+               goto put_pru1;
        }
        prueth->pruss = pruss;
 
@@ -1569,18 +1570,15 @@ put_mem:
        }
        pruss_put(prueth->pruss);
 
-put_pru:
-       if (eth1_node) {
-               if (prueth->pru1)
-                       pru_rproc_put(prueth->pru1);
-               of_node_put(eth1_node);
-       }
-
-       if (eth0_node) {
-               if (prueth->pru0)
-                       pru_rproc_put(prueth->pru0);
-               of_node_put(eth0_node);
-       }
+put_pru1:
+       if (eth1_node)
+               pru_rproc_put(prueth->pru1);
+put_pru0:
+       if (eth0_node)
+               pru_rproc_put(prueth->pru0);
+put_eth:
+       of_node_put(eth1_node);
+       of_node_put(eth0_node);
 
        return ret;
 }