[PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[cgel.zte]

From: Lv Ruyi <lv.ruyi@zte.com.cn>

Application of sizeof to pointer yields the number of bytes of the pointer,
but it should use the length of buffer in the code.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
---
 drivers/firmware/tegra/bpmp-debugfs.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/tegra/bpmp-debugfs.c b/drivers/firmware/tegra/bpmp-debugfs.c
index 6d66fe03fb6a..fd89899aeeed 100644
--- a/drivers/firmware/tegra/bpmp-debugfs.c
+++ b/drivers/firmware/tegra/bpmp-debugfs.c
@@ -77,13 +77,14 @@ static const char *get_filename(struct tegra_bpmp *bpmp,
 	const char *root_path, *filename = NULL;
 	char *root_path_buf;
 	size_t root_len;
+	size_t root_path_buf_len = 512;
 
-	root_path_buf = kzalloc(512, GFP_KERNEL);
+	root_path_buf = kzalloc(root_path_buf_len, GFP_KERNEL);
 	if (!root_path_buf)
 		goto out;
 
 	root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
-				sizeof(root_path_buf));
+				root_path_buf_len);
 	if (IS_ERR(root_path))
 		goto out;
 
-- 
2.25.1

Re: [PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[Jon Hunter]

Hi Lv,	

On 09/10/2021 09:59, cgel.zte@gmail.com wrote:
> From: Lv Ruyi <lv.ruyi@zte.com.cn>
> 
> Application of sizeof to pointer yields the number of bytes of the pointer,
> but it should use the length of buffer in the code.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
> ---
>   drivers/firmware/tegra/bpmp-debugfs.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/tegra/bpmp-debugfs.c b/drivers/firmware/tegra/bpmp-debugfs.c
> index 6d66fe03fb6a..fd89899aeeed 100644
> --- a/drivers/firmware/tegra/bpmp-debugfs.c
> +++ b/drivers/firmware/tegra/bpmp-debugfs.c
> @@ -77,13 +77,14 @@ static const char *get_filename(struct tegra_bpmp *bpmp,
>   	const char *root_path, *filename = NULL;
>   	char *root_path_buf;
>   	size_t root_len;
> +	size_t root_path_buf_len = 512;
>   
> -	root_path_buf = kzalloc(512, GFP_KERNEL);
> +	root_path_buf = kzalloc(root_path_buf_len, GFP_KERNEL);
>   	if (!root_path_buf)
>   		goto out;
>   
>   	root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
> -				sizeof(root_path_buf));
> +				root_path_buf_len);
>   	if (IS_ERR(root_path))
>   		goto out;
>   
> 

Thanks for fixing this! I just noticed that the debugfs for BPMP is 
broken on -next right now and this fixes it. We should add the fixes tag ...

Fixes: 06c2d9a078ab ("firmware: tegra: Reduce stack usage")

Otherwise ...

Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>

Arnd, do you want to pick this up?

Jon

-- 
nvpublic

Re: [PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[Jon Hunter]

On 14/10/2021 19:26, Jon Hunter wrote:
> Hi Lv,
> 
> On 09/10/2021 09:59, cgel.zte@gmail.com wrote:
>> From: Lv Ruyi <lv.ruyi@zte.com.cn>
>>
>> Application of sizeof to pointer yields the number of bytes of the 
>> pointer,
>> but it should use the length of buffer in the code.
>>
>> Reported-by: Zeal Robot <zealci@zte.com.cn>
>> Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
>> ---
>>   drivers/firmware/tegra/bpmp-debugfs.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/firmware/tegra/bpmp-debugfs.c 
>> b/drivers/firmware/tegra/bpmp-debugfs.c
>> index 6d66fe03fb6a..fd89899aeeed 100644
>> --- a/drivers/firmware/tegra/bpmp-debugfs.c
>> +++ b/drivers/firmware/tegra/bpmp-debugfs.c
>> @@ -77,13 +77,14 @@ static const char *get_filename(struct tegra_bpmp 
>> *bpmp,
>>       const char *root_path, *filename = NULL;
>>       char *root_path_buf;
>>       size_t root_len;
>> +    size_t root_path_buf_len = 512;
>> -    root_path_buf = kzalloc(512, GFP_KERNEL);
>> +    root_path_buf = kzalloc(root_path_buf_len, GFP_KERNEL);
>>       if (!root_path_buf)
>>           goto out;
>>       root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
>> -                sizeof(root_path_buf));
>> +                root_path_buf_len);
>>       if (IS_ERR(root_path))
>>           goto out;
>>
> 
> Thanks for fixing this! I just noticed that the debugfs for BPMP is 
> broken on -next right now and this fixes it. We should add the fixes tag 
> ...
> 
> Fixes: 06c2d9a078ab ("firmware: tegra: Reduce stack usage")
> 
> Otherwise ...
> 
> Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
> Tested-by: Jon Hunter <jonathanh@nvidia.com>
> 
> Arnd, do you want to pick this up?

Nevermind I see that Thierry queued up the offending patch and so I will 
ask Thierry to pick this up.

Jon

-- 
nvpublic

Re: [PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[Thierry Reding]

[-- Attachment #1: Type: text/plain, Size: 485 bytes --]

On Sat, Oct 09, 2021 at 08:59:00AM +0000, cgel.zte@gmail.com wrote:
> From: Lv Ruyi <lv.ruyi@zte.com.cn>
> 
> Application of sizeof to pointer yields the number of bytes of the pointer,
> but it should use the length of buffer in the code.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
> ---
>  drivers/firmware/tegra/bpmp-debugfs.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Applied, thanks.

Thierry

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH V1] firmware: tegra: fix error application of sizeof to pointer

[Jon Hunter]

Hi Thierry,

On 18/10/2021 15:06, Thierry Reding wrote:
> On Sat, Oct 09, 2021 at 08:59:00AM +0000, cgel.zte@gmail.com wrote:
>> From: Lv Ruyi <lv.ruyi@zte.com.cn>
>>
>> Application of sizeof to pointer yields the number of bytes of the pointer,
>> but it should use the length of buffer in the code.
>>
>> Reported-by: Zeal Robot <zealci@zte.com.cn>
>> Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
>> ---
>>   drivers/firmware/tegra/bpmp-debugfs.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> Applied, thanks.


We need to apply this as a fix for v5.16. I am still seeing a failure 
for reading the BPMP debugfs on v5.16-rc3.

Jon

-- 
nvpublic