Le 25/06/2018 à 14:45, Stafford Horne a écrit :
When compiling with GCC 9.0.0 I am seeing the following warning:
In function ‘fill_kobj_path’,
inlined from ‘kobject_get_path’ at lib/kobject.c:155:2:
lib/kobject.c:128:3: warning: ‘strncpy’ output truncated before terminating nul copying as many bytes from a string as its length [-Wstringop-truncation]
strncpy(path + length, kobject_name(parent), cur);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/kobject.c: In function ‘kobject_get_path’:
lib/kobject.c:125:13: note: length computed here
int cur = strlen(kobject_name(parent));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
This is not really an issue since the buffer we are writing to is
pre-zero'd and we have already allocated the buffer based on the
calculated strlen size and accounted for the terminating '\0'.
Just use memcpy() instead.
If we are already sure the destination is big enough, why not just do a
strcpy() and drop the 'cur = strlen()' ?
Christophe
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Eric Biggers <ebiggers3@xxxxxxxxx>
Signed-off-by: Stafford Horne <shorne@xxxxxxxxx>
---
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) = '/';
}
