[PATCH 4.4 292/312] net: ethoc: Fix early error paths

From: Greg Kroah-Hartman
Date: Fri May 08 2020 - 08:48:20 EST


From: Florian Fainelli <f.fainelli@xxxxxxxxx>

commit 386512d18b268c6182903239f9f3390f03ce4c7b upstream.

In case any operation fails before we can successfully go the point
where we would register a MDIO bus, we would be going to an error label
which involves unregistering then freeing this yet to be created MDIO
bus. Update all error paths to go to label free which is the only one
valid until either the clock is enabled, or the MDIO bus is allocated
and registered. This fixes kernel oops observed while trying to
dereference the MDIO bus structure which is not yet allocated.

Fixes: a1702857724f ("net: Add support for the OpenCores 10/100 Mbps Ethernet MAC.")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/ethernet/ethoc.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/net/ethernet/ethoc.c
+++ b/drivers/net/ethernet/ethoc.c
@@ -1088,7 +1088,7 @@ static int ethoc_probe(struct platform_d
if (!priv->iobase) {
dev_err(&pdev->dev, "cannot remap I/O memory space\n");
ret = -ENXIO;
- goto error;
+ goto free;
}

if (netdev->mem_end) {
@@ -1097,7 +1097,7 @@ static int ethoc_probe(struct platform_d
if (!priv->membase) {
dev_err(&pdev->dev, "cannot remap memory space\n");
ret = -ENXIO;
- goto error;
+ goto free;
}
} else {
/* Allocate buffer memory */
@@ -1108,7 +1108,7 @@ static int ethoc_probe(struct platform_d
dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
buffer_size);
ret = -ENOMEM;
- goto error;
+ goto free;
}
netdev->mem_end = netdev->mem_start + buffer_size;
priv->dma_alloc = buffer_size;
@@ -1122,7 +1122,7 @@ static int ethoc_probe(struct platform_d
128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
if (num_bd < 4) {
ret = -ENODEV;
- goto error;
+ goto free;
}
priv->num_bd = num_bd;
/* num_tx must be a power of two */
@@ -1135,7 +1135,7 @@ static int ethoc_probe(struct platform_d
priv->vma = devm_kzalloc(&pdev->dev, num_bd*sizeof(void *), GFP_KERNEL);
if (!priv->vma) {
ret = -ENOMEM;
- goto error;
+ goto free;
}

/* Allow the platform setup code to pass in a MAC address. */