[PATCH next] drivers/video/fbdev/sis: Replace strlen() strcpy() pair with strscpy()

[PATCH next] drivers/video/fbdev/sis: Replace strlen() strcpy() pair with strscpy()

[david.laight.linux]

From: David Laight <david.laight.linux@gmail.com>

Use the result of strscpy() for the overflow check.

Signed-off-by: David Laight <david.laight.linux@gmail.com>
---
This is one of a group of patches that remove potentially unbounded
strcpy() calls.

They are mostly replaced by strscpy() or, when strlen() has just been
called, with memcpy() (usually including the '\0').

Calls with copy string literals into arrays are left unchanged.
They are safe and easily detected as such.

The changes were made by getting the compiler to detect the calls and
then fixing the code by hand.

Note that all the changes are only compile tested.

Some Makefiles were changed to allow files to contain strcpy().
As well as 'difficult to fix' files, this included 'show' functions
as they really need to use sysfs_emit() or seq_printf().

All the patches are being sent individually to avoid very long cc lists.
Apologies for the terse commit messages and likely unexpected tags.
(There are about 100 patches in total.)

 drivers/video/fbdev/sis/sis_main.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/sis/sis_main.c b/drivers/video/fbdev/sis/sis_main.c
index 84567d67f71d..95f976b49143 100644
--- a/drivers/video/fbdev/sis/sis_main.c
+++ b/drivers/video/fbdev/sis/sis_main.c
@@ -204,8 +204,7 @@ static void sisfb_search_mode(char *name, bool quiet)
 		return;
 	}
 
-	if(strlen(name) <= 19) {
-		strcpy(strbuf1, name);
+	if (strscpy(strbuf1, name) > 0) {
 		for(i = 0; i < strlen(strbuf1); i++) {
 			if(strbuf1[i] < '0' || strbuf1[i] > '9') strbuf1[i] = ' ';
 		}
-- 
2.39.5

Re: [PATCH next] drivers/video/fbdev/sis: Replace strlen() strcpy() pair with strscpy()

[Helge Deller]

On 6/6/26 22:27, david.laight.linux@gmail.com wrote:
> From: David Laight <david.laight.linux@gmail.com>
> 
> Use the result of strscpy() for the overflow check.
> 
> Signed-off-by: David Laight <david.laight.linux@gmail.com>

Hi David,

I've applied your 5 patches to the fbdev git tree.

Thanks!
Helge

Re: [PATCH next] drivers/video/fbdev/sis: Replace strlen() strcpy() pair with strscpy()

[David Laight]

On Sun, 7 Jun 2026 17:50:00 +0200
Helge Deller <deller@gmx.de> wrote:

> On 6/6/26 22:27, david.laight.linux@gmail.com wrote:
> > From: David Laight <david.laight.linux@gmail.com>
> > 
> > Use the result of strscpy() for the overflow check.
> > 
> > Signed-off-by: David Laight <david.laight.linux@gmail.com>  
> 
> Hi David,
> 
> I've applied your 5 patches to the fbdev git tree.
> 
> Thanks!
> Helge

Thanks, that'll be 5 that don't come around when I try the same test
in a couple of months time :-)

David