linux-kernel - [PATCH 4.9 004/101] kobject: Replace strncpy with memcpy

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Message-Id: <20181206143011.869256388@linuxfoundation.org>
Date:   Thu,  6 Dec 2018 15:38:03 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Guenter Roeck <linux@...ck-us.net>
Subject: [PATCH 4.9 004/101] kobject: Replace strncpy with memcpy

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Guenter Roeck <linux@...ck-us.net>

commit 77d2a24b6107bd9b3bf2403a65c1428a9da83dd0 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 lib/kobject.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -127,7 +127,7 @@ static void fill_kobj_path(struct kobjec
 		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) = '/';
 	}