[PATCH] [v2] crypto: ccp - fix memleak in ccp_init_dm_workarea

[PATCH] [v2] crypto: ccp - fix memleak in ccp_init_dm_workarea

[Dinghao Liu]

When dma_map_single() fails, wa->address is supposed to be freed
by the callers of ccp_init_dm_workarea() through ccp_dm_free().
However, many of the call spots don't expect to have to call
ccp_dm_free() on failure of ccp_init_dm_workarea(), which may
lead to a memleak. Let's free wa->address in ccp_init_dm_workarea()
when dma_map_single() fails.

Fixes: 63b945091a07 ("crypto: ccp - CCP device driver and interface support")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
---

Changelog:

v2: -Improve the commit message.
    -Set wa->address to NULL after kfree() to prevent double-free.
---
 drivers/crypto/ccp/ccp-ops.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index aa4e1a500691..cb8e99936abb 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c
@@ -179,8 +179,11 @@ static int ccp_init_dm_workarea(struct ccp_dm_workarea *wa,
 
 		wa->dma.address = dma_map_single(wa->dev, wa->address, len,
 						 dir);
-		if (dma_mapping_error(wa->dev, wa->dma.address))
+		if (dma_mapping_error(wa->dev, wa->dma.address)) {
+			kfree(wa->address);
+			wa->address = NULL;
 			return -ENOMEM;
+		}
 
 		wa->dma.length = len;
 	}
-- 
2.17.1

Re: [PATCH] [v2] crypto: ccp - fix memleak in ccp_init_dm_workarea

[Tom Lendacky]

On 11/26/23 21:47, Dinghao Liu wrote:
> When dma_map_single() fails, wa->address is supposed to be freed
> by the callers of ccp_init_dm_workarea() through ccp_dm_free().
> However, many of the call spots don't expect to have to call
> ccp_dm_free() on failure of ccp_init_dm_workarea(), which may
> lead to a memleak. Let's free wa->address in ccp_init_dm_workarea()
> when dma_map_single() fails.
> 
> Fixes: 63b945091a07 ("crypto: ccp - CCP device driver and interface support")
> Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>

Acked-by: Tom Lendacky <thomas.lendacky@amd.com>

> ---
> 
> Changelog:
> 
> v2: -Improve the commit message.
>      -Set wa->address to NULL after kfree() to prevent double-free.
> ---
>   drivers/crypto/ccp/ccp-ops.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
> index aa4e1a500691..cb8e99936abb 100644
> --- a/drivers/crypto/ccp/ccp-ops.c
> +++ b/drivers/crypto/ccp/ccp-ops.c
> @@ -179,8 +179,11 @@ static int ccp_init_dm_workarea(struct ccp_dm_workarea *wa,
>   
>   		wa->dma.address = dma_map_single(wa->dev, wa->address, len,
>   						 dir);
> -		if (dma_mapping_error(wa->dev, wa->dma.address))
> +		if (dma_mapping_error(wa->dev, wa->dma.address)) {
> +			kfree(wa->address);
> +			wa->address = NULL;
>   			return -ENOMEM;
> +		}
>   
>   		wa->dma.length = len;
>   	}

Re: [PATCH] [v2] crypto: ccp - fix memleak in ccp_init_dm_workarea

[Herbert Xu]

On Mon, Nov 27, 2023 at 11:47:10AM +0800, Dinghao Liu wrote:
> When dma_map_single() fails, wa->address is supposed to be freed
> by the callers of ccp_init_dm_workarea() through ccp_dm_free().
> However, many of the call spots don't expect to have to call
> ccp_dm_free() on failure of ccp_init_dm_workarea(), which may
> lead to a memleak. Let's free wa->address in ccp_init_dm_workarea()
> when dma_map_single() fails.
> 
> Fixes: 63b945091a07 ("crypto: ccp - CCP device driver and interface support")
> Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
> ---
> 
> Changelog:
> 
> v2: -Improve the commit message.
>     -Set wa->address to NULL after kfree() to prevent double-free.
> ---
>  drivers/crypto/ccp/ccp-ops.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt