[PATCH] memory: samsung: exynos-srom: Fix of_iomap leak in exynos_srom_probe

The current error handling in exynos_srom_probe() has a resource leak
in the of_platform_populate() failure path. When this function fails
after successful resource allocation, srom->reg_base is not released.

To fix this issue, replace of_iomap() with
devm_platform_ioremap_resource(). devm_platform_ioremap_resource()
is a specialized function for platform devices.
It allows 'srom->reg_base' to be automatically released whether the
probe function succeeds or fails.

Besides, use IS_ERR() instead of !srom->reg_base
as the return value of devm_platform_ioremap_resource()
can either be a pointer to the remapped memory or
an ERR_PTR() encoded error code if the operation fails.

Signed-off-by: Zhen Ni <redacted>
---
 drivers/memory/samsung/exynos-srom.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/samsung/exynos-srom.c b/drivers/memory/samsung/exynos-srom.c
index e73dd330af47..d913fb901973 100644
--- a/drivers/memory/samsung/exynos-srom.c
+++ b/drivers/memory/samsung/exynos-srom.c

@@ -121,20 +121,18 @@ static int exynos_srom_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	srom->dev = dev;
-	srom->reg_base = of_iomap(np, 0);
-	if (!srom->reg_base) {
+	srom->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(srom->reg_base)) {
 		dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
-		return -ENOMEM;
+		return PTR_ERR(srom->reg_base);
 	}
 
 	platform_set_drvdata(pdev, srom);
 
 	srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
 						      ARRAY_SIZE(exynos_srom_offsets));
-	if (!srom->reg_offset) {
-		iounmap(srom->reg_base);
+	if (!srom->reg_offset)
 		return -ENOMEM;
-	}
 
 	for_each_child_of_node(np, child) {
 		if (exynos_srom_configure_bank(srom, child)) {

-- 
2.20.1

On 31/07/2025 10:33, Zhen Ni wrote:

The current error handling in exynos_srom_probe() has a resource leak
in the of_platform_populate() failure path. When this function fails
after successful resource allocation, srom->reg_base is not released.

To fix this issue, replace of_iomap() with
devm_platform_ioremap_resource(). devm_platform_ioremap_resource()
is a specialized function for platform devices.

Don't explain us kernel code. Drop sentence.

It allows 'srom->reg_base' to be automatically released whether the
probe function succeeds or fails.

It's obvious.

Besides, use IS_ERR() instead of !srom->reg_base

I don't understand this. You keep explaining the code and this suggests
you made change here not related to original case. Can you return
srom->reg_base here? No?

as the return value of devm_platform_ioremap_resource()
can either be a pointer to the remapped memory or
an ERR_PTR() encoded error code if the operation fails.

Missing fixes and cc-stable.

How did you test it?

Best regards,
Krzysztof

On 31/07/2025 11:40, zhen.ni wrote:

Hi,

During static analysis with Smatch, I identified the following issue:

drivers/memory/samsung/exynos-srom.c:155 exynos_srom_probe()
warn: 'srom->reg_base' from of_iomap() not released on lines: 155.

Nothing in commit msg explained you used Smatch. You must describe the
tools you use.

Problem analysis:
1. In exynos_srom_probe(), the reg_base resource is acquired via of_iomap()
2. The of_platform_populate() call at the end of the function has a 
possible failure path:

Above is AI/LLM output?

root = root ? of_node_get(root) : of_find_node_by_path("/");
if (!root)
      return -EINVAL; // Failure return point

3. When this path is taken, reg_base is not released, causing a resource 
leak

Verification:
After applying the patch, the Smatch warning is resolved

This means no testing. You should mention it as well.

Don't top post. See netiquette.


Best regards,
Krzysztof

Hi,

During static analysis with Smatch, I identified the following issue:

drivers/memory/samsung/exynos-srom.c:155 exynos_srom_probe()
warn: 'srom->reg_base' from of_iomap() not released on lines: 155.

Problem analysis:
1. In exynos_srom_probe(), the reg_base resource is acquired via of_iomap()
2. The of_platform_populate() call at the end of the function has a 
possible failure path:

root = root ? of_node_get(root) : of_find_node_by_path("/");
if (!root)
      return -EINVAL; // Failure return point

3. When this path is taken, reg_base is not released, causing a resource 
leak

Verification:
After applying the patch, the Smatch warning is resolved


Best regards,
Zhen


在 2025/7/31 17:06, Krzysztof Kozlowski 写道:

On 31/07/2025 10:33, Zhen Ni wrote:

quoted

The current error handling in exynos_srom_probe() has a resource leak
in the of_platform_populate() failure path. When this function fails
after successful resource allocation, srom->reg_base is not released.

To fix this issue, replace of_iomap() with
devm_platform_ioremap_resource(). devm_platform_ioremap_resource()
is a specialized function for platform devices.

Don't explain us kernel code. Drop sentence.

quoted

It allows 'srom->reg_base' to be automatically released whether the
probe function succeeds or fails.

It's obvious.

quoted

Besides, use IS_ERR() instead of !srom->reg_base

I don't understand this. You keep explaining the code and this suggests
you made change here not related to original case. Can you return
srom->reg_base here? No?

quoted

as the return value of devm_platform_ioremap_resource()
can either be a pointer to the remapped memory or
an ERR_PTR() encoded error code if the operation fails.

Missing fixes and cc-stable.

quoted

Signed-off-by: Zhen Ni <redacted>
---
  drivers/memory/samsung/exynos-srom.c | 10 ++++------
  1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/samsung/exynos-srom.c b/drivers/memory/samsung/exynos-srom.c
index e73dd330af47..d913fb901973 100644
--- a/drivers/memory/samsung/exynos-srom.c
+++ b/drivers/memory/samsung/exynos-srom.c

@@ -121,20 +121,18 @@ static int exynos_srom_probe(struct platform_device *pdev)
  		return -ENOMEM;
  
  	srom->dev = dev;
-	srom->reg_base = of_iomap(np, 0);
-	if (!srom->reg_base) {
+	srom->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(srom->reg_base)) {
  		dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
-		return -ENOMEM;
+		return PTR_ERR(srom->reg_base);

How did you test it?

Best regards,
Krzysztof

The of_platform_populate() call at the end of the function has a
possible failure path, causing a resource leak.

Replace of_iomap() with devm_platform_ioremap_resource() to ensure
automatic cleanup of srom->reg_base.

This issue was detected by smatch static analysis:
drivers/memory/samsung/exynos-srom.c:155 exynos_srom_probe()warn:
'srom->reg_base' from of_iomap() not released on lines: 155.

Fixes: 8ac2266d8831 ("memory: samsung: exynos-srom: Add support for bank configuration")
Cc: stable@vger.kernel.org
Signed-off-by: Zhen Ni <redacted>
---
chanegs in v2:
- Update commit msg
---
 drivers/memory/samsung/exynos-srom.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/samsung/exynos-srom.c b/drivers/memory/samsung/exynos-srom.c
index e73dd330af47..d913fb901973 100644
--- a/drivers/memory/samsung/exynos-srom.c
+++ b/drivers/memory/samsung/exynos-srom.c

@@ -121,20 +121,18 @@ static int exynos_srom_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	srom->dev = dev;
-	srom->reg_base = of_iomap(np, 0);
-	if (!srom->reg_base) {
+	srom->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(srom->reg_base)) {
 		dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
-		return -ENOMEM;
+		return PTR_ERR(srom->reg_base);
 	}
 
 	platform_set_drvdata(pdev, srom);
 
 	srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
 						      ARRAY_SIZE(exynos_srom_offsets));
-	if (!srom->reg_offset) {
-		iounmap(srom->reg_base);
+	if (!srom->reg_offset)
 		return -ENOMEM;
-	}
 
 	for_each_child_of_node(np, child) {
 		if (exynos_srom_configure_bank(srom, child)) {

-- 
2.20.1

On Wed, 06 Aug 2025 10:55:38 +0800, Zhen Ni wrote:

The of_platform_populate() call at the end of the function has a
possible failure path, causing a resource leak.

Replace of_iomap() with devm_platform_ioremap_resource() to ensure
automatic cleanup of srom->reg_base.

This issue was detected by smatch static analysis:
drivers/memory/samsung/exynos-srom.c:155 exynos_srom_probe()warn:
'srom->reg_base' from of_iomap() not released on lines: 155.

[...]

Applied, thanks!

[1/1] memory: samsung: exynos-srom: Fix of_iomap leak in exynos_srom_probe
      https://git.kernel.org/krzk/linux-mem-ctrl/c/6744085079e785dae5f7a2239456135407c58b25

Best regards,
-- 
Krzysztof Kozlowski [off-list ref]