2023-04-17 03:29:12

by Chao Wang

Subject: [PATCH] iommu: Fix unwind goto issue

Smatch complains that
drivers/iommu/rockchip-iommu.c:1306 rk_iommu_probe() warn: missing unwind goto?

The rk_iommu_probe function, after obtaining the irq value through
platform_get_irq, directly returns an error if the returned value
is negative, without releasing any resources.

Fix this by adding a new error handling label "err_pm_disable" and
use a goto statement to redirect to the error handling process. In
order to preserve the original semantics, set err to the value of irq.

Fixes: 1aa55ca9b14a ("iommu/rockchip: Move irq request past pm_runtime_enable")
Signed-off-by: Chao Wang <[email protected]>
Reviewed-by: Dongliang Mu <[email protected]>
---
This issue is found by static analysis and remains untested.
---
drivers/iommu/rockchip-iommu.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index f30db22ea5d7..31cd1e2929e9 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -1302,20 +1302,22 @@ static int rk_iommu_probe(struct platform_device *pdev)
for (i = 0; i < iommu->num_irq; i++) {
int irq = platform_get_irq(pdev, i);

- if (irq < 0)
- return irq;
+ if (irq < 0) {
+ err = irq;
+ goto err_pm_disable;
+ }

err = devm_request_irq(iommu->dev, irq, rk_iommu_irq,
IRQF_SHARED, dev_name(dev), iommu);
- if (err) {
- pm_runtime_disable(dev);
- goto err_remove_sysfs;
- }
+ if (err)
+ goto err_pm_disable;
}

dma_set_mask_and_coherent(dev, rk_ops->dma_bit_mask);

return 0;
+err_pm_disable:
+ pm_runtime_disable(dev);
err_remove_sysfs:
iommu_device_sysfs_remove(&iommu->iommu);
err_put_group:
--
2.34.1

2023-04-17 08:23:30

by Heiko Stuebner

Subject: Re: [PATCH] iommu: Fix unwind goto issue

Am Montag, 17. April 2023, 05:04:21 CEST schrieb Chao Wang:
> Smatch complains that
> drivers/iommu/rockchip-iommu.c:1306 rk_iommu_probe() warn: missing unwind goto?
>
> The rk_iommu_probe function, after obtaining the irq value through
> platform_get_irq, directly returns an error if the returned value
> is negative, without releasing any resources.
>
> Fix this by adding a new error handling label "err_pm_disable" and
> use a goto statement to redirect to the error handling process. In
> order to preserve the original semantics, set err to the value of irq.
>
> Fixes: 1aa55ca9b14a ("iommu/rockchip: Move irq request past pm_runtime_enable")
> Signed-off-by: Chao Wang <[email protected]>
> Reviewed-by: Dongliang Mu <[email protected]>

Looking at the code, that makes a lot of sense.

Reviewed-by: Heiko Stuebner <[email protected]>

2023-05-22 15:18:21

by Joerg Roedel

Subject: Re: [PATCH] iommu: Fix unwind goto issue

On Mon, Apr 17, 2023 at 03:04:21AM +0000, Chao Wang wrote:
> drivers/iommu/rockchip-iommu.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)

Applied for 6.4, thanks.