[PATCH v2] rbd: replace strcpy() with strscpy()

[Siddarth Gundu <siddarthsgml@gmail.com>]

strcpy() is deprecated; use strscpy() instead.

Both the destination and source buffer are of fixed length
so strscpy with 2-arguments is used.

Introduce a typedef for cookie array to improve code clarity.

Link: https://github.com/KSPP/linux/issues/88
Signed-off-by: Siddarth Gundu <siddarthsgml@gmail.com>
---
changes since v1
- added a typedef for cookie arrays

About the typedef: I was a bit hesitant to add it since the kernel
style guide is against adding new typedef but I wanted to follow 
the review feedback for this.

 drivers/block/rbd.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index faafd7ff43d6..863d9c591aa5 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -46,11 +46,14 @@
 #include <linux/slab.h>
 #include <linux/idr.h>
 #include <linux/workqueue.h>
+#include <linux/string.h>
 
 #include "rbd_types.h"
 
 #define RBD_DEBUG	/* Activate rbd_assert() calls */
 
+typedef char rbd_cookie_t[32];
+
 /*
  * Increment the given counter and return its updated value.
  * If the counter is already 0 it will not be incremented.
@@ -411,7 +414,7 @@ struct rbd_device {
 
 	struct rw_semaphore	lock_rwsem;
 	enum rbd_lock_state	lock_state;
-	char			lock_cookie[32];
+	rbd_cookie_t		lock_cookie;
 	struct rbd_client_id	owner_cid;
 	struct work_struct	acquired_lock_work;
 	struct work_struct	released_lock_work;
@@ -3649,12 +3652,12 @@ static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
 	mutex_unlock(&rbd_dev->watch_mutex);
 }
 
-static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
+static void __rbd_lock(struct rbd_device *rbd_dev, const rbd_cookie_t 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);
 }
@@ -3665,7 +3668,7 @@ static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
 static int rbd_lock(struct rbd_device *rbd_dev)
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
-	char cookie[32];
+	rbd_cookie_t cookie;
 	int ret;
 
 	WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
@@ -4581,7 +4584,7 @@ static void rbd_unregister_watch(struct rbd_device *rbd_dev)
 static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
-	char cookie[32];
+	rbd_cookie_t cookie;
 	int ret;
 
 	if (!rbd_quiesce_lock(rbd_dev))
-- 
2.43.0