Re: [PATCH] iommu/intel-iommu: fix memory leak in intel_iommu_put_resv_regions()

From: Auger Eric
Date: Wed Jan 16 2019 - 15:43:53 EST


Hi Gerald,

On 1/16/19 8:11 PM, Gerald Schaefer wrote:
> Commit 9d3a4de4cb8d ("iommu: Disambiguate MSI region types") changed
> the reserved region type in intel_iommu_get_resv_regions() from
> IOMMU_RESV_RESERVED to IOMMU_RESV_MSI, but it forgot to also change
> the type in intel_iommu_put_resv_regions().
>
> This leads to a memory leak, because now the check in
> intel_iommu_put_resv_regions() for IOMMU_RESV_RESERVED will never
> be true, and no allocated regions will be freed.
>
> Fix this by changing the region type in intel_iommu_put_resv_regions()
> to IOMMU_RESV_MSI, matching the type of the allocated regions.
>
> Fixes: 9d3a4de4cb8d ("iommu: Disambiguate MSI region types")
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.11+
> Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>

Thanks

Eric

> ---
> drivers/iommu/intel-iommu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index 048b5ab36a02..b83e0f2025bb 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -5295,7 +5295,7 @@ static void intel_iommu_put_resv_regions(struct device *dev,
> struct iommu_resv_region *entry, *next;
>
> list_for_each_entry_safe(entry, next, head, list) {
> - if (entry->type == IOMMU_RESV_RESERVED)
> + if (entry->type == IOMMU_RESV_MSI)
> kfree(entry);
> }
> }
>