Re: [PATCH v2] iommu/amd: Fix possible memory leak of 'domain'

From: Vasant Hegde <vasant.hegde@amd.com>
To: Su Hui <suhui@nfschina.com>, Joerg Roedel <joro@8bytes.org>,
	Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
	Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>
Cc: kevin.tian@intel.com, jgg@ziepe.ca, iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] iommu/amd: Fix possible memory leak of 'domain'
Date: Thu, 8 Jun 2023 09:47:43 +0530	[thread overview]
Message-ID: <af26f1e2-da2e-814d-0a8c-5209bba12aba@amd.com> (raw)
In-Reply-To: <20230608021933.856045-1-suhui@nfschina.com>

On 6/8/2023 7:49 AM, Su Hui wrote:
> Move allocation code down to avoid memory leak.
> 
> Fixes: 29f54745f245 ("iommu/amd: Add missing domain type checks")
> Signed-off-by: Su Hui <suhui@nfschina.com>

Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>


-Vasant


> ---
> Changes in v2:
> 	change code order is better and more consistent with other
> drivers. 
>  drivers/iommu/amd/iommu.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index dc1ec6849775..e8a2e5984acb 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -2078,10 +2078,6 @@ static struct protection_domain *protection_domain_alloc(unsigned int type)
>  	int mode = DEFAULT_PGTABLE_LEVEL;
>  	int ret;
>  
> -	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
> -	if (!domain)
> -		return NULL;
> -
>  	/*
>  	 * Force IOMMU v1 page table when iommu=pt and
>  	 * when allocating domain for pass-through devices.
> @@ -2097,6 +2093,10 @@ static struct protection_domain *protection_domain_alloc(unsigned int type)
>  		return NULL;
>  	}
>  
> +	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
> +	if (!domain)
> +		return NULL;
> +
>  	switch (pgtable) {
>  	case AMD_IOMMU_V1:
>  		ret = protection_domain_init_v1(domain, mode);