[PATCH] of: module: remove strlen() call in of_modalias()

[PATCH] of: module: remove strlen() call in of_modalias()

[Sergey Shtylyov]

In of_modalias(), there's no dire need to call strlen() (and then add 1
to its result to account for the 'C' char preceding the compat string).
Replace that strlen() with snprintf() (currently below it) -- this way,
we always try to print the compat string but then only advance the str
and len parameters iff the comapt string fit into the remaining buffer
space...

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>

---
The patch is against the dt/next branch of Rob Herring's linux.git repo...

 drivers/of/module.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Index: linux/drivers/of/module.c
===================================================================
--- linux.orig/drivers/of/module.c
+++ linux/drivers/of/module.c
@@ -35,12 +35,10 @@ ssize_t of_modalias(const struct device_
 	str += csize;
 
 	of_property_for_each_string(np, "compatible", p, compat) {
-		csize = strlen(compat) + 1;
+		csize = snprintf(str, len, "C%s", compat);
 		tsize += csize;
 		if (csize >= len)
 			continue;
-
-		csize = snprintf(str, len, "C%s", compat);
 		for (c = str; c; ) {
 			c = strchr(c, ' ');
 			if (c)

Re: [PATCH] of: module: remove strlen() call in of_modalias()

[Sergey Shtylyov]

On 10/15/24 11:15 PM, Sergey Shtylyov wrote:

> In of_modalias(), there's no dire need to call strlen() (and then add 1
> to its result to account for the 'C' char preceding the compat string).
> Replace that strlen() with snprintf() (currently below it) -- this way,
> we always try to print the compat string but then only advance the str
> and len parameters iff the comapt string fit into the remaining buffer

    Oops, compat! :-)

> space...
> 
> Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
[...]

MBR, Sergey

Re: [PATCH] of: module: remove strlen() call in of_modalias()

[Rob Herring (Arm)]

On Tue, 15 Oct 2024 23:15:04 +0300, Sergey Shtylyov wrote:
> In of_modalias(), there's no dire need to call strlen() (and then add 1
> to its result to account for the 'C' char preceding the compat string).
> Replace that strlen() with snprintf() (currently below it) -- this way,
> we always try to print the compat string but then only advance the str
> and len parameters iff the comapt string fit into the remaining buffer
> space...
> 
> Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
> 
> ---
> The patch is against the dt/next branch of Rob Herring's linux.git repo...
> 
>  drivers/of/module.c |    4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 

Fixed the typo and applied, thanks!

Rob