[linux-next,v2] accessibility: speakup: use strscpy() to instead of strncpy()

Message ID 202212051928467539184@zte.com.cn
State New
Headers
Series [linux-next,v2] accessibility: speakup: use strscpy() to instead of strncpy() |

Commit Message

Yang Yang Dec. 5, 2022, 11:28 a.m. UTC
  From: Xu Panda <xu.panda@zte.com.cn>

The implementation of strscpy() is more robust and safer.
That's now the recommended way to copy NUL terminated strings.
---
change for v2
 - fix the mistake of eating one character when len > 250,
thanks to Samuel Thibault.
---

Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
Signed-off-by: Yang Yang <yang.yang29@zte.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
---
 drivers/accessibility/speakup/kobjects.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
  

Comments

Samuel Thibault Dec. 5, 2022, 12:37 p.m. UTC | #1
yang.yang29@zte.com.cn, le lun. 05 déc. 2022 19:28:46 +0800, a ecrit:
> From: Xu Panda <xu.panda@zte.com.cn>
> 
> The implementation of strscpy() is more robust and safer.
> That's now the recommended way to copy NUL terminated strings.
> ---
> change for v2
>  - fix the mistake of eating one character when len > 250,
> thanks to Samuel Thibault.
> ---
> 
> Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
> Signed-off-by: Yang Yang <yang.yang29@zte.com>
> Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

It's not really a signed-off from my side, I just did a review :)

but with that version,

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

> ---
>  drivers/accessibility/speakup/kobjects.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/accessibility/speakup/kobjects.c b/drivers/accessibility/speakup/kobjects.c
> index a7522d409802..c1ef48280f3c 100644
> --- a/drivers/accessibility/speakup/kobjects.c
> +++ b/drivers/accessibility/speakup/kobjects.c
> @@ -426,8 +426,7 @@ static ssize_t synth_direct_store(struct kobject *kobj,
>  	spin_lock_irqsave(&speakup_info.spinlock, flags);
>  	while (len > 0) {
>  		bytes = min_t(size_t, len, 250);
> -		strncpy(tmp, ptr, bytes);
> -		tmp[bytes] = '\0';
> +		strscpy(tmp, ptr, bytes + 1);
>  		string_unescape_any_inplace(tmp);
>  		synth_printf("%s", tmp);
>  		ptr += bytes;
> -- 
> 2.15.2
>
  

Patch

diff --git a/drivers/accessibility/speakup/kobjects.c b/drivers/accessibility/speakup/kobjects.c
index a7522d409802..c1ef48280f3c 100644
--- a/drivers/accessibility/speakup/kobjects.c
+++ b/drivers/accessibility/speakup/kobjects.c
@@ -426,8 +426,7 @@  static ssize_t synth_direct_store(struct kobject *kobj,
 	spin_lock_irqsave(&speakup_info.spinlock, flags);
 	while (len > 0) {
 		bytes = min_t(size_t, len, 250);
-		strncpy(tmp, ptr, bytes);
-		tmp[bytes] = '\0';
+		strscpy(tmp, ptr, bytes + 1);
 		string_unescape_any_inplace(tmp);
 		synth_printf("%s", tmp);
 		ptr += bytes;