staging: speakup: Replace strncpy with memcpy
authorGuenter Roeck <linux@roeck-us.net>
Sun, 1 Jul 2018 20:57:24 +0000 (13:57 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 17 Dec 2018 08:28:55 +0000 (09:28 +0100)
commit fd29edc7232bc19f969e8f463138afc5472b3d5f upstream.

gcc 8.1.0 generates the following warnings.

drivers/staging/speakup/kobjects.c: In function 'punc_store':
drivers/staging/speakup/kobjects.c:522:2: warning:
'strncpy' output truncated before terminating nul
copying as many bytes from a string as its length
drivers/staging/speakup/kobjects.c:504:6: note: length computed here

drivers/staging/speakup/kobjects.c: In function 'synth_store':
drivers/staging/speakup/kobjects.c:391:2: warning:
'strncpy' output truncated before terminating nul
copying as many bytes from a string as its length
drivers/staging/speakup/kobjects.c:388:8: 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@roeck-us.net>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/speakup/kobjects.c

index ca85476..23256bb 100644 (file)
@@ -387,7 +387,7 @@ static ssize_t synth_store(struct kobject *kobj, struct kobj_attribute *attr,
        len = strlen(buf);
        if (len < 2 || len > 9)
                return -EINVAL;
-       strncpy(new_synth_name, buf, len);
+       memcpy(new_synth_name, buf, len);
        if (new_synth_name[len - 1] == '\n')
                len--;
        new_synth_name[len] = '\0';
@@ -518,7 +518,7 @@ static ssize_t punc_store(struct kobject *kobj, struct kobj_attribute *attr,
                return -EINVAL;
        }
 
-       strncpy(punc_buf, buf, x);
+       memcpy(punc_buf, buf, x);
 
        while (x && punc_buf[x - 1] == '\n')
                x--;