linux-kernel - [PATCH] kobject: Replace strncpy with memcpy

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Message-Id: <1530478636-16555-1-git-send-email-linux@roeck-us.net>
Date:   Sun,  1 Jul 2018 13:57:16 -0700
From:   Guenter Roeck <linux@...ck-us.net>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     linux-kernel@...r.kernel.org, Guenter Roeck <linux@...ck-us.net>
Subject: [PATCH] kobject:  Replace strncpy with memcpy

gcc 8.1.0 complains:

lib/kobject.c:128:3: warning:
	'strncpy' output truncated before terminating nul copying as many
	bytes from a string as its length [-Wstringop-truncation]
lib/kobject.c: In function 'kobject_get_path':
lib/kobject.c:125:13: note: length computed here

Using strncpy() is indeed less than perfect since the length of data to
be copied has already been determined with strlen(). Replace strncpy()
with memcpy() to address the warning and optimize the code a little.

Signed-off-by: Guenter Roeck <linux@...ck-us.net>
---
 lib/kobject.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/kobject.c b/lib/kobject.c
index 18989b5b3b56..e876957743c8 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -125,7 +125,7 @@ static void fill_kobj_path(struct kobject *kobj, char *path, int length)
 		int cur = strlen(kobject_name(parent));
 		/* back up enough to print this name with '/' */
 		length -= cur;
-		strncpy(path + length, kobject_name(parent), cur);
+		memcpy(path + length, kobject_name(parent), cur);
 		*(path + --length) = '/';
 	}
 
-- 
2.7.4