All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Krzysztof Wilczyński" <kw@linux.com>
To: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	Ryder Lee <ryder.lee@mediatek.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Rob Herring <robh@kernel.org>,
	linux-pci@vger.kernel.org, linux-mediatek@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] PCI: mediatek: Add missing of_node_put() to fix reference leak
Date: Wed, 20 Jan 2021 18:48:10 +0000	[thread overview]
Message-ID: <20210120184810.3068794-1-kw@linux.com> (raw)

The for_each_available_child_of_node helper internally makes use of the
of_get_next_available_child() which performs an of_node_get() on each
iteration when searching for next available child node.

Should an available child node be found, then it would return a device
node pointer with reference count incremented, thus early return from
the middle of the loop requires an explicit of_node_put() to prevent
reference count leak.

To stop the reference leak, explicitly call of_node_put() before
returning after an error occurred.

Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/controller/pcie-mediatek.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index cf4c18f0c25a..23548b517e4b 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1035,14 +1035,14 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		err = of_pci_get_devfn(child);
 		if (err < 0) {
 			dev_err(dev, "failed to parse devfn: %d\n", err);
-			return err;
+			goto error_put_node;
 		}
 
 		slot = PCI_SLOT(err);
 
 		err = mtk_pcie_parse_port(pcie, child, slot);
 		if (err)
-			return err;
+			goto error_put_node;
 	}
 
 	err = mtk_pcie_subsys_powerup(pcie);
@@ -1058,6 +1058,9 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		mtk_pcie_subsys_powerdown(pcie);
 
 	return 0;
+error_put_node:
+	of_node_put(child);
+	return err;
 }
 
 static int mtk_pcie_probe(struct platform_device *pdev)
-- 
2.30.0


WARNING: multiple messages have this Message-ID (diff)
From: "Krzysztof Wilczyński" <kw@linux.com>
To: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Rob Herring <robh@kernel.org>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	linux-pci@vger.kernel.org, Ryder Lee <ryder.lee@mediatek.com>,
	linux-mediatek@lists.infradead.org,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] PCI: mediatek: Add missing of_node_put() to fix reference leak
Date: Wed, 20 Jan 2021 18:48:10 +0000	[thread overview]
Message-ID: <20210120184810.3068794-1-kw@linux.com> (raw)

The for_each_available_child_of_node helper internally makes use of the
of_get_next_available_child() which performs an of_node_get() on each
iteration when searching for next available child node.

Should an available child node be found, then it would return a device
node pointer with reference count incremented, thus early return from
the middle of the loop requires an explicit of_node_put() to prevent
reference count leak.

To stop the reference leak, explicitly call of_node_put() before
returning after an error occurred.

Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/controller/pcie-mediatek.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index cf4c18f0c25a..23548b517e4b 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1035,14 +1035,14 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		err = of_pci_get_devfn(child);
 		if (err < 0) {
 			dev_err(dev, "failed to parse devfn: %d\n", err);
-			return err;
+			goto error_put_node;
 		}
 
 		slot = PCI_SLOT(err);
 
 		err = mtk_pcie_parse_port(pcie, child, slot);
 		if (err)
-			return err;
+			goto error_put_node;
 	}
 
 	err = mtk_pcie_subsys_powerup(pcie);
@@ -1058,6 +1058,9 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		mtk_pcie_subsys_powerdown(pcie);
 
 	return 0;
+error_put_node:
+	of_node_put(child);
+	return err;
 }
 
 static int mtk_pcie_probe(struct platform_device *pdev)
-- 
2.30.0


_______________________________________________
Linux-mediatek mailing list
Linux-mediatek@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-mediatek

WARNING: multiple messages have this Message-ID (diff)
From: "Krzysztof Wilczyński" <kw@linux.com>
To: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	linux-pci@vger.kernel.org, Ryder Lee <ryder.lee@mediatek.com>,
	linux-mediatek@lists.infradead.org,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] PCI: mediatek: Add missing of_node_put() to fix reference leak
Date: Wed, 20 Jan 2021 18:48:10 +0000	[thread overview]
Message-ID: <20210120184810.3068794-1-kw@linux.com> (raw)

The for_each_available_child_of_node helper internally makes use of the
of_get_next_available_child() which performs an of_node_get() on each
iteration when searching for next available child node.

Should an available child node be found, then it would return a device
node pointer with reference count incremented, thus early return from
the middle of the loop requires an explicit of_node_put() to prevent
reference count leak.

To stop the reference leak, explicitly call of_node_put() before
returning after an error occurred.

Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
---
 drivers/pci/controller/pcie-mediatek.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index cf4c18f0c25a..23548b517e4b 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1035,14 +1035,14 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		err = of_pci_get_devfn(child);
 		if (err < 0) {
 			dev_err(dev, "failed to parse devfn: %d\n", err);
-			return err;
+			goto error_put_node;
 		}
 
 		slot = PCI_SLOT(err);
 
 		err = mtk_pcie_parse_port(pcie, child, slot);
 		if (err)
-			return err;
+			goto error_put_node;
 	}
 
 	err = mtk_pcie_subsys_powerup(pcie);
@@ -1058,6 +1058,9 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 		mtk_pcie_subsys_powerdown(pcie);
 
 	return 0;
+error_put_node:
+	of_node_put(child);
+	return err;
 }
 
 static int mtk_pcie_probe(struct platform_device *pdev)
-- 
2.30.0


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

             reply	other threads:[~2021-01-20 19:31 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-20 18:48 Krzysztof Wilczyński [this message]
2021-01-20 18:48 ` [PATCH] PCI: mediatek: Add missing of_node_put() to fix reference leak Krzysztof Wilczyński
2021-01-20 18:48 ` Krzysztof Wilczyński
2021-01-25 17:34 ` Lorenzo Pieralisi
2021-01-25 17:34   ` Lorenzo Pieralisi
2021-01-25 17:34   ` Lorenzo Pieralisi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210120184810.3068794-1-kw@linux.com \
    --to=kw@linux.com \
    --cc=bhelgaas@google.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=matthias.bgg@gmail.com \
    --cc=robh@kernel.org \
    --cc=ryder.lee@mediatek.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.