[PATCH next] drivers/scsi/aic7xxx/aic79xx_osm: Use kstrdup() instead of kmalloc() and strcpy()

[PATCH next] drivers/scsi/aic7xxx/aic79xx_osm: Use kstrdup() instead of kmalloc() and strcpy()

[david.laight.linux]

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

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/scsi/aic7xxx/aic79xx_osm.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c
index feb1707feb7e..97ebee94230e 100644
--- a/drivers/scsi/aic7xxx/aic79xx_osm.c
+++ b/drivers/scsi/aic7xxx/aic79xx_osm.c
@@ -1233,11 +1233,9 @@ ahd_linux_register_host(struct ahd_softc *ahd, struct scsi_host_template *templa
 	ahd_set_unit(ahd, ahd_linux_unit++);
 	ahd_unlock(ahd, &s);
 	sprintf(buf, "scsi%d", host->host_no);
-	new_name = kmalloc(strlen(buf) + 1, GFP_ATOMIC);
-	if (new_name != NULL) {
-		strcpy(new_name, buf);
+	new_name = kstrdup(buf, GFP_ATOMIC);
+	if (new_name != NULL)
 		ahd_set_name(ahd, new_name);
-	}
 	host->unique_id = ahd->unit;
 	ahd_linux_initialize_scsi_bus(ahd);
 	ahd_intr_enable(ahd, TRUE);
-- 
2.39.5

Re: [PATCH next] drivers/scsi/aic7xxx/aic79xx_osm: Use kstrdup() instead of kmalloc() and strcpy()

[Christophe JAILLET]

Le 06/06/2026 à 22:26, david.laight.linux@gmail.com a écrit :
> From: David Laight <david.laight.linux@gmail.com>
> 
> 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/scsi/aic7xxx/aic79xx_osm.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c
> index feb1707feb7e..97ebee94230e 100644
> --- a/drivers/scsi/aic7xxx/aic79xx_osm.c
> +++ b/drivers/scsi/aic7xxx/aic79xx_osm.c
> @@ -1233,11 +1233,9 @@ ahd_linux_register_host(struct ahd_softc *ahd, struct scsi_host_template *templa
>   	ahd_set_unit(ahd, ahd_linux_unit++);
>   	ahd_unlock(ahd, &s);
>   	sprintf(buf, "scsi%d", host->host_no);
> -	new_name = kmalloc(strlen(buf) + 1, GFP_ATOMIC);
> -	if (new_name != NULL) {
> -		strcpy(new_name, buf);
> +	new_name = kstrdup(buf, GFP_ATOMIC);

I think that kasprintf() would simplify code and do the same.

Otherwise, s/sprintf/snprintf/ could be done, as in the patch for 
aic7xxx_osm.c

CJ

> +	if (new_name != NULL)
>   		ahd_set_name(ahd, new_name);
> -	}
>   	host->unique_id = ahd->unit;
>   	ahd_linux_initialize_scsi_bus(ahd);
>   	ahd_intr_enable(ahd, TRUE);

Re: [PATCH next] drivers/scsi/aic7xxx/aic79xx_osm: Use kstrdup() instead of kmalloc() and strcpy()

[David Laight]

On Sat, 6 Jun 2026 23:42:36 +0200
Christophe JAILLET <christophe.jaillet@wanadoo.fr> wrote:

> Le 06/06/2026 à 22:26, david.laight.linux@gmail.com a écrit :
> > From: David Laight <david.laight.linux@gmail.com>
> > 
> > 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/scsi/aic7xxx/aic79xx_osm.c | 6 ++----
> >   1 file changed, 2 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/scsi/aic7xxx/aic79xx_osm.c b/drivers/scsi/aic7xxx/aic79xx_osm.c
> > index feb1707feb7e..97ebee94230e 100644
> > --- a/drivers/scsi/aic7xxx/aic79xx_osm.c
> > +++ b/drivers/scsi/aic7xxx/aic79xx_osm.c
> > @@ -1233,11 +1233,9 @@ ahd_linux_register_host(struct ahd_softc *ahd, struct scsi_host_template *templa
> >   	ahd_set_unit(ahd, ahd_linux_unit++);
> >   	ahd_unlock(ahd, &s);
> >   	sprintf(buf, "scsi%d", host->host_no);
> > -	new_name = kmalloc(strlen(buf) + 1, GFP_ATOMIC);
> > -	if (new_name != NULL) {
> > -		strcpy(new_name, buf);
> > +	new_name = kstrdup(buf, GFP_ATOMIC);  
> 
> I think that kasprintf() would simplify code and do the same.
> 
> Otherwise, s/sprintf/snprintf/ could be done, as in the patch for 
> aic7xxx_osm.c

Looks like I missed the sprintf() here.
I was doing a lot of simple changes and trying not to rewrite too much.

Looking a bit deeper into the ahd code there is an 8 byte pointer
that usually references an 8 byte buffer.
A fixed char name[16] will use less memory overall.
The only other thing it ever references is the result of:
	sprintf(buf, "ahd_pci:%d:%d:%d",
		ahd_get_pci_bus(pci),
		ahd_get_pci_slot(pci),
		ahd_get_pci_function(pci));
which it only does temporarily during ahd_linux_pci_dev_probe().
Even that is usually less than 16 bytes.
Given the probe function pretty much never fails, the scsi%d
string could be generated earlier with just a trace to tie
the two together.

But that is far beyond this set of changes.

Doing a 'v2' that isn't just an edit of the email will be a pita.

-- David

> 
> CJ
> 
> > +	if (new_name != NULL)
> >   		ahd_set_name(ahd, new_name);
> > -	}
> >   	host->unique_id = ahd->unit;
> >   	ahd_linux_initialize_scsi_bus(ahd);
> >   	ahd_intr_enable(ahd, TRUE);  
>