The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.
581 static int mtk_iommu_probe(struct platform_device *pdev)
582 {
...
626 for (i = 0; i < larb_nr; i++) {
627 struct device_node *larbnode;
...
631 larbnode = of_parse_phandle(...);
632 if (!larbnode)
633 return -EINVAL;
634
635 if (!of_device_is_available(larbnode))
636 continue; ---> leaked here
637
...
643 if (!plarbdev)
644 return -EPROBE_DEFER; ---> leaked here
...
647 component_match_add_release(dev, &match, release_of,
648 compare_of, larbnode);
---> release_of will call of_node_put
649 }
...
650
Detected by coccinelle with the following warnings:
./drivers/iommu/mtk_iommu.c:644:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 631, but without a corresponding object release within this function.
Signed-off-by: Wen Yang <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
drivers/iommu/mtk_iommu.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index de3e022..b66d11b 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -632,16 +632,20 @@ static int mtk_iommu_probe(struct platform_device *pdev)
if (!larbnode)
return -EINVAL;
- if (!of_device_is_available(larbnode))
+ if (!of_device_is_available(larbnode)) {
+ of_node_put(larbnode);
continue;
+ }
ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id);
if (ret)/* The id is consecutive if there is no this property */
id = i;
plarbdev = of_find_device_by_node(larbnode);
- if (!plarbdev)
+ if (!plarbdev) {
+ of_node_put(larbnode);
return -EPROBE_DEFER;
+ }
data->smi_imu.larb_imu[id].dev = &plarbdev->dev;
component_match_add_release(dev, &match, release_of,
--
2.9.5
On 17/04/2019 04:41, Wen Yang wrote:
> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
>
> 581 static int mtk_iommu_probe(struct platform_device *pdev)
> 582 {
> ...
> 626 for (i = 0; i < larb_nr; i++) {
> 627 struct device_node *larbnode;
> ...
> 631 larbnode = of_parse_phandle(...);
> 632 if (!larbnode)
> 633 return -EINVAL;
> 634
> 635 if (!of_device_is_available(larbnode))
> 636 continue; ---> leaked here
> 637
> ...
> 643 if (!plarbdev)
> 644 return -EPROBE_DEFER; ---> leaked here
> ...
> 647 component_match_add_release(dev, &match, release_of,
> 648 compare_of, larbnode);
> ---> release_of will call of_node_put
> 649 }
> ...
> 650
>
> Detected by coccinelle with the following warnings:
> ./drivers/iommu/mtk_iommu.c:644:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 631, but without a corresponding object release within this function.
>
> Signed-off-by: Wen Yang <[email protected]>
> Cc: Joerg Roedel <[email protected]>
> Cc: Matthias Brugger <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
Reviewed-by: Matthias Brugger <[email protected]>
> ---
> drivers/iommu/mtk_iommu.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index de3e022..b66d11b 100644
> --- a/drivers/iommu/mtk_iommu.c
> +++ b/drivers/iommu/mtk_iommu.c
> @@ -632,16 +632,20 @@ static int mtk_iommu_probe(struct platform_device *pdev)
> if (!larbnode)
> return -EINVAL;
>
> - if (!of_device_is_available(larbnode))
> + if (!of_device_is_available(larbnode)) {
> + of_node_put(larbnode);
> continue;
> + }
>
> ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id);
> if (ret)/* The id is consecutive if there is no this property */
> id = i;
>
> plarbdev = of_find_device_by_node(larbnode);
> - if (!plarbdev)
> + if (!plarbdev) {
> + of_node_put(larbnode);
> return -EPROBE_DEFER;
> + }
> data->smi_imu.larb_imu[id].dev = &plarbdev->dev;
>
> component_match_add_release(dev, &match, release_of,
>
> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
Can a splitting of this information into two sentences help?
> 581 static int mtk_iommu_probe(struct platform_device *pdev)
> 582 {
> ...
I suggest to reconsider such a commit description once more.
Would it be better to mention that another function call should be added
in two if branches so that the exception handling would be completed
(instead of copying source code where a software update should become
clear also from the provided diff hunk)?
Regards,
Markus
> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
Can a splitting of this information into two sentences help?
> 581 static int mtk_iommu_probe(struct platform_device *pdev)
> 582 {
> ...
I suggest to reconsider such a commit description once more.
Would it be better to mention that another function call should be added
in two if branches so that the exception handling would be completed
(instead of copying source code where a software update should become
clear also from the provided diff hunk)?
Regards,
Markus
On Wed, Apr 17, 2019 at 10:41:19AM +0800, Wen Yang wrote:
> drivers/iommu/mtk_iommu.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
Applied, thanks.