4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
[ Upstream commit f990874b1c98fe8e57ee9385669f501822979258 ]
If of_clk_add_provider() fails in ca8210_register_ext_clock(),
it calls clk_unregister() to release priv->clk and returns an
error. However, the caller ca8210_probe() then calls ca8210_remove(),
where priv->clk is freed again in ca8210_unregister_ext_clock(). In
this case, a use-after-free may happen in the second time we call
clk_unregister().
Fix this by removing the first clk_unregister(). Also, priv->clk could
be an error code on failure of clk_register_fixed_rate(). Use
IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock().
Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver")
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
Message-ID: <20231007033049.22353-1-dinghao.liu@xxxxxxxxxx>
Signed-off-by: Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ieee802154/ca8210.c | 17 +++--------------
1 file changed, 3 insertions(+), 14 deletions(-)
diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
index 4ec65582eaf70..d903106436dc6 100644
--- a/drivers/net/ieee802154/ca8210.c
+++ b/drivers/net/ieee802154/ca8210.c
@@ -2782,7 +2782,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
struct device_node *np = spi->dev.of_node;
struct ca8210_priv *priv = spi_get_drvdata(spi);
struct ca8210_platform_data *pdata = spi->dev.platform_data;
- int ret = 0;
if (!np)
return -EFAULT;
@@ -2799,18 +2798,8 @@ static int ca8210_register_ext_clock(struct spi_device *spi)
dev_crit(&spi->dev, "Failed to register external clk\n");
return PTR_ERR(priv->clk);
}
- ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
- if (ret) {
- clk_unregister(priv->clk);
- dev_crit(
- &spi->dev,
- "Failed to register external clock as clock provider\n"
- );
- } else {
- dev_info(&spi->dev, "External clock set as clock provider\n");
- }
- return ret;
+ return of_clk_add_provider(np, of_clk_src_simple_get, priv->clk);
}
/**
@@ -2822,8 +2811,8 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi)
{
struct ca8210_priv *priv = spi_get_drvdata(spi);
- if (!priv->clk)
- return
+ if (IS_ERR_OR_NULL(priv->clk))
+ return;
of_clk_del_provider(spi->dev.of_node);
clk_unregister(priv->clk);
--
2.40.1
