The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 29afbd769ca338fa14cbfbbc824f7dc457ed7f2e Mon Sep 17 00:00:00 2001 From: Dan Carpenter dan.carpenter@oracle.com Date: Sat, 15 Jan 2022 14:51:46 +0300 Subject: [PATCH] phy: cadence: Sierra: fix error handling bugs in probe()

There are two bugs in the error handling: 1: If devm_of_phy_provider_register() fails then there was no cleanup. 2: The error handling called of_node_put(child) improperly leading to a use after free. We are only holding the reference inside the loop so the last two gotos after the loop lead to a use after free bug. Fix this by cleaning up the partial allocations (or partial iterations) in the loop before doing the goto.

Fixes: a43f72ae136a ("phy: cadence: Sierra: Change MAX_LANES of Sierra to 16") Fixes: 44d30d622821 ("phy: cadence: Add driver for Sierra PHY") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Link: https://lore.kernel.org/r/20220115115146.GC7552@kili Signed-off-by: Vinod Koul vkoul@kernel.org

diff --git a/drivers/phy/cadence/phy-cadence-sierra.c b/drivers/phy/cadence/phy-cadence-sierra.c index da24acd26666..e265647e29a2 100644 --- a/drivers/phy/cadence/phy-cadence-sierra.c +++ b/drivers/phy/cadence/phy-cadence-sierra.c @@ -1338,7 +1338,7 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; const struct cdns_sierra_data *data; unsigned int id_value; - int i, ret, node = 0; + int ret, node = 0; void __iomem *base; struct device_node *dn = dev->of_node, *child;

@@ -1416,7 +1416,8 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev) dev_err(dev, "failed to get reset %s\n", child->full_name); ret = PTR_ERR(sp->phys[node].lnk_rst); - goto put_child2; + of_node_put(child); + goto put_control; }

if (!sp->autoconf) { @@ -1424,7 +1425,9 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev) if (ret) { dev_err(dev, "missing property in node %s\n", child->name); - goto put_child; + of_node_put(child); + reset_control_put(sp->phys[node].lnk_rst); + goto put_control; } }

@@ -1434,7 +1437,9 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev)

if (IS_ERR(gphy)) { ret = PTR_ERR(gphy); - goto put_child; + of_node_put(child); + reset_control_put(sp->phys[node].lnk_rst); + goto put_control; } sp->phys[node].phy = gphy; phy_set_drvdata(gphy, &sp->phys[node]); @@ -1446,26 +1451,28 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev) if (sp->num_lanes > SIERRA_MAX_LANES) { ret = -EINVAL; dev_err(dev, "Invalid lane configuration\n"); - goto put_child2; + goto put_control; }

/* If more than one subnode, configure the PHY as multilink */ if (!sp->autoconf && sp->nsubnodes > 1) { ret = cdns_sierra_phy_configure_multilink(sp); if (ret) - goto put_child2; + goto put_control; }

pm_runtime_enable(dev); phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); - return PTR_ERR_OR_ZERO(phy_provider); - -put_child: - node++; -put_child2: - for (i = 0; i < node; i++) - reset_control_put(sp->phys[i].lnk_rst); - of_node_put(child); + if (IS_ERR(phy_provider)) { + ret = PTR_ERR(phy_provider); + goto put_control; + } + + return 0; + +put_control: + while (--node >= 0) + reset_control_put(sp->phys[node].lnk_rst); clk_disable: cdns_sierra_phy_disable_clocks(sp); reset_control_assert(sp->apb_rst);