[PATCH next] drivers/block/rbd: Use strscpy() to copy strings into arrays

[PATCH next] drivers/block/rbd: Use strscpy() to copy strings into arrays

[david.laight.linux]

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

Replacing strcpy() with strscpy() ensures than overflow of the target
buffer cannot happen.

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/block/rbd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 4065336ebd1f..632fa2d56ea0 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -3672,7 +3672,7 @@ static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
 	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
 
 	rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
-	strcpy(rbd_dev->lock_cookie, cookie);
+	strscpy(rbd_dev->lock_cookie, cookie);
 	rbd_set_owner_cid(rbd_dev, &cid);
 	queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
 }
-- 
2.39.5

Re: [PATCH next] drivers/block/rbd: Use strscpy() to copy strings into arrays

[Alex Elder]

On 6/6/26 3:27 PM, david.laight.linux@gmail.com wrote:
> From: David Laight <david.laight.linux@gmail.com>
> 
> Replacing strcpy() with strscpy() ensures than overflow of the target
> buffer cannot happen.
> 
> 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/block/rbd.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
> index 4065336ebd1f..632fa2d56ea0 100644
> --- a/drivers/block/rbd.c
> +++ b/drivers/block/rbd.c
> @@ -3672,7 +3672,7 @@ static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
>   	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
>   
>   	rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
> -	strcpy(rbd_dev->lock_cookie, cookie);
> +	strscpy(rbd_dev->lock_cookie, cookie);

This looks good.  The rbd_device->lock_cookie is a 32 byte
array.

Cookies passed in are always a 32 byte array (despite the
function only requiring a string pointer).

Reviewed-by: Alex Elder <elder@riscstar.com>

>   	rbd_set_owner_cid(rbd_dev, &cid);
>   	queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
>   }