Re: [PATCH 3/3] dmaengine: dw-edma: increase size of 'name' in debugfs code

From: Serge Semin <fancer.lancer@gmail.com>
To: Vinod Koul <vkoul@kernel.org>
Cc: dmaengine@vger.kernel.org, Manivannan Sadhasivam <mani@kernel.org>
Subject: Re: [PATCH 3/3] dmaengine: dw-edma: increase size of 'name' in debugfs code
Date: Mon, 22 Jan 2024 12:32:16 +0300	[thread overview]
Message-ID: <acwdroop2av6sdfqca63dds7dyscauumypmrmooyrcquhy3jd3@5mf2utzdrlxh> (raw)
In-Reply-To: <20240119124944.152562-3-vkoul@kernel.org>

Hi Vinod

On Fri, Jan 19, 2024 at 06:19:44PM +0530, Vinod Koul wrote:
> We seem to have hit warnings of 'output may be truncated' which is fixed
> by increasing the size of 'name'
> 
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c: In function ‘dw_hdma_v0_debugfs_on’:
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c:125:50: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
>   125 |                 snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
>       |                                                  ^~
> 
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c: In function ‘dw_hdma_v0_debugfs_on’:
> drivers/dma/dw-edma/dw-hdma-v0-debugfs.c:142:50: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
>   142 |                 snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
>       |                                                  ^~
> drivers/dma/dw-edma/dw-edma-v0-debugfs.c: In function ‘dw_edma_debugfs_regs_wr’:
> drivers/dma/dw-edma/dw-edma-v0-debugfs.c:193:50: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
>   193 |                 snprintf(name, sizeof(name), "%s:%d", CHANNEL_STR, i);
>       |                                                  ^~
> 
> Signed-off-by: Vinod Koul <vkoul@kernel.org>

Thanks for submitting the patch. I've got a similar one hanging out in
my local repo. I was going to submit it together with a few another
fixes, but then I had to switch my efforts to another task and
successfully forgot about this warning fix.

Please note the warning you stated above is false-positive in this
context since a name of the channel is printed to the string buffer in a
format like "channel:<int>", where "<int>" is the channel number and
which never supposed to be greater than eight. Anyway here is my tag:

Reviewed-by: Serge Semin <fancer.lancer@gmail.com>

Here are three more tags which might be also reasonable to add:

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311030041.DznTeuS5-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202311030809.CjufIFaP-lkp@intel.com/

-Serge(y)

> ---
>  drivers/dma/dw-edma/dw-edma-v0-debugfs.c | 4 ++--
>  drivers/dma/dw-edma/dw-hdma-v0-debugfs.c | 4 ++--
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma/dw-edma/dw-edma-v0-debugfs.c b/drivers/dma/dw-edma/dw-edma-v0-debugfs.c
> index 0745d9e7d259..406f169b09a7 100644
> --- a/drivers/dma/dw-edma/dw-edma-v0-debugfs.c
> +++ b/drivers/dma/dw-edma/dw-edma-v0-debugfs.c
> @@ -176,7 +176,7 @@ dw_edma_debugfs_regs_wr(struct dw_edma *dw, struct dentry *dent)
>  	};
>  	struct dentry *regs_dent, *ch_dent;
>  	int nr_entries, i;
> -	char name[16];
> +	char name[32];
>  
>  	regs_dent = debugfs_create_dir(WRITE_STR, dent);
>  
> @@ -239,7 +239,7 @@ static noinline_for_stack void dw_edma_debugfs_regs_rd(struct dw_edma *dw,
>  	};
>  	struct dentry *regs_dent, *ch_dent;
>  	int nr_entries, i;
> -	char name[16];
> +	char name[32];
>  
>  	regs_dent = debugfs_create_dir(READ_STR, dent);
>  
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> index 520c81978b08..dcdc57fe976c 100644
> --- a/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-debugfs.c
> @@ -116,7 +116,7 @@ static void dw_hdma_debugfs_regs_ch(struct dw_edma *dw, enum dw_edma_dir dir,
>  static void dw_hdma_debugfs_regs_wr(struct dw_edma *dw, struct dentry *dent)
>  {
>  	struct dentry *regs_dent, *ch_dent;
> -	char name[16];
> +	char name[32];
>  	int i;
>  
>  	regs_dent = debugfs_create_dir(WRITE_STR, dent);
> @@ -133,7 +133,7 @@ static void dw_hdma_debugfs_regs_wr(struct dw_edma *dw, struct dentry *dent)
>  static void dw_hdma_debugfs_regs_rd(struct dw_edma *dw, struct dentry *dent)
>  {
>  	struct dentry *regs_dent, *ch_dent;
> -	char name[16];
> +	char name[32];
>  	int i;
>  
>  	regs_dent = debugfs_create_dir(READ_STR, dent);
> -- 
> 2.43.0
> 
> 