Re: [lvc-project] [PATCH 5.10 1/1] Backport of rpmsg: qcom: glink: replace strncpy() with strscpy_pad()

[Alexey Khoroshilov]

Dear Andrew,

For backporting patches you should follow the following pattern:

---------------------------------------------
Subject: [PATCH 5.10 1/1] {ORIGINAL COMMIT SUBJECT}

From:  {ORIGINAL AUTHOR EMAIL}

commit {ORIGINAL COMMIT HASH} upstream.

{ORIGINAL COMMIT TEXT INCLUDING ALL SIGGNED_OFF}

Signed-off-by: {YOUR EMAIL}
---
{ORIGINAL PATCH}
---------------------------------------------

e.g.
---------------------------------------------
Subject: [PATCH 5.10 1/1] rpmsg: qcom: glink: replace strncpy() with
strscpy_pad()

From:  Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>

commit 766279a8f85df32345dbda03b102ca1ee3d5ddea upstream.

The use of strncpy() is considered deprecated for NUL-terminated
strings[1]. Replace strncpy() with strscpy_pad(), to keep existing
pad-behavior of strncpy, similarly to commit 08de420a8014 ("rpmsg:
glink: Replace strncpy() with strscpy_pad()").  This fixes W=1 warning:

  In function ‘qcom_glink_rx_close’,
    inlined from ‘qcom_glink_work’ at
../drivers/rpmsg/qcom_glink_native.c:1638:4:
  drivers/rpmsg/qcom_glink_native.c:1549:17: warning: ‘strncpy’
specified bound 32 equals destination size [-Wstringop-truncation]
   1549 |                 strncpy(chinfo.name, channel->name,
sizeof(chinfo.name));

[1]
https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Reviewed-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Link:
https://lore.kernel.org/r/20220519073330.7187-1-krzysztof.kozlowski@xxxxxxxxxx

Signed-off-by: Andrew Chernyakov <acherniakov@xxxxxxxxxxxxx>
---
.....
---------------------------------------------

Please update the patch according the requirements and resend.

Thank you,
Alexey


On 07.10.2022 13:41, Andrew Chernyakov wrote:
> The use of strncpy() is considered deprecated for NULL-terminated
> strings[1]. Replace strncpy() with strscpy_pad(), to keep existing
> pad-behavior of strncpy, strncpy was found on line 1424 of
> /drivers/rpmsg/qcom_glink_native.c.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Andrew Chernyakov <acherniakov@xxxxxxxxxxxxx>
> ---
>  drivers/rpmsg/qcom_glink_native.c | 2 +-
>  drivers/rpmsg/qcom_smd.c          | 4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
> index 4840886532ff..66a63b205744 100644
> --- a/drivers/rpmsg/qcom_glink_native.c
> +++ b/drivers/rpmsg/qcom_glink_native.c
> @@ -1424,7 +1424,7 @@ static int qcom_glink_rx_open(struct qcom_glink *glink, unsigned int rcid,
>  		}
>  
>  		rpdev->ept = &channel->ept;
> -		strncpy(rpdev->id.name, name, RPMSG_NAME_SIZE);
> +		strscpy_pad(rpdev->id.name, name, RPMSG_NAME_SIZE);
>  		rpdev->src = RPMSG_ADDR_ANY;
>  		rpdev->dst = RPMSG_ADDR_ANY;
>  		rpdev->ops = &glink_device_ops;
> diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
> index 0b1e853d8c91..b5167ef93abf 100644
> --- a/drivers/rpmsg/qcom_smd.c
> +++ b/drivers/rpmsg/qcom_smd.c
> @@ -1073,7 +1073,7 @@ static int qcom_smd_create_device(struct qcom_smd_channel *channel)
>  
>  	/* Assign public information to the rpmsg_device */
>  	rpdev = &qsdev->rpdev;
> -	strncpy(rpdev->id.name, channel->name, RPMSG_NAME_SIZE);
> +	strscpy_pad(rpdev->id.name, channel->name, RPMSG_NAME_SIZE);
>  	rpdev->src = RPMSG_ADDR_ANY;
>  	rpdev->dst = RPMSG_ADDR_ANY;
>  
> @@ -1304,7 +1304,7 @@ static void qcom_channel_state_worker(struct work_struct *work)
>  
>  		spin_unlock_irqrestore(&edge->channels_lock, flags);
>  
> -		strncpy(chinfo.name, channel->name, sizeof(chinfo.name));
> +		strscpy_pad(chinfo.name, channel->name, sizeof(chinfo.name));
>  		chinfo.src = RPMSG_ADDR_ANY;
>  		chinfo.dst = RPMSG_ADDR_ANY;
>  		rpmsg_unregister_device(&edge->dev, &chinfo);
>