2021-08-20 07:48:20

by Yang Yingliang

Subject: [PATCH -next] iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group()

Add the missing unlock before return from function arm_smmu_device_group()
in the error handling case.

Fixes: b1a1347912a7 ("iommu/arm-smmu: Fix race condition during iommu_group creation")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Yang Yingliang <[email protected]>
---
drivers/iommu/arm/arm-smmu/arm-smmu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 73893180ec7e..4bc75c4ce402 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1478,8 +1478,10 @@ static struct iommu_group *arm_smmu_device_group(struct device *dev)
mutex_lock(&smmu->stream_map_mutex);
for_each_cfg_sme(cfg, fwspec, i, idx) {
if (group && smmu->s2crs[idx].group &&
- group != smmu->s2crs[idx].group)
+ group != smmu->s2crs[idx].group) {
+ mutex_unlock(&smmu->stream_map_mutex);
return ERR_PTR(-EINVAL);
+ }

group = smmu->s2crs[idx].group;
}
--
2.25.1

2021-08-20 10:43:43

by Will Deacon

Subject: Re: [PATCH -next] iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group()

On Fri, Aug 20, 2021 at 03:49:49PM +0800, Yang Yingliang wrote:
> Add the missing unlock before return from function arm_smmu_device_group()
> in the error handling case.
>
> Fixes: b1a1347912a7 ("iommu/arm-smmu: Fix race condition during iommu_group creation")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Yang Yingliang <[email protected]>
> ---
> drivers/iommu/arm/arm-smmu/arm-smmu.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index 73893180ec7e..4bc75c4ce402 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -1478,8 +1478,10 @@ static struct iommu_group *arm_smmu_device_group(struct device *dev)
> mutex_lock(&smmu->stream_map_mutex);
> for_each_cfg_sme(cfg, fwspec, i, idx) {
> if (group && smmu->s2crs[idx].group &&
> - group != smmu->s2crs[idx].group)
> + group != smmu->s2crs[idx].group) {
> + mutex_unlock(&smmu->stream_map_mutex);
> return ERR_PTR(-EINVAL);
> + }

Urgh, I should really have spotted that in review. Thanks:

Acked-by: Will Deacon <[email protected]>

Joerg -- please can you throw this on top?

Will

2021-08-20 12:40:02

by Joerg Roedel

Subject: Re: [PATCH -next] iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group()

On Fri, Aug 20, 2021 at 11:41:11AM +0100, Will Deacon wrote:
> Joerg -- please can you throw this on top?

Sure, now applied, thanks.