libsmack: fix label validation in smack_new_label_from_path

Off-by-one length was returned from the function. This patch fixes
the regression by doing full validation for the SMACK label.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

diff --git a/libsmack/libsmack.c b/libsmack/libsmack.c
index d5ba7dd..0052c1d 100644 (file)
--- a/libsmack/libsmack.c
+++ b/libsmack/libsmack.c
@@ -581,22 +581,21 @@ ssize_t smack_new_label_from_socket(int fd, char **label)
 ssize_t smack_new_label_from_path(const char *path, const char *xattr, 
                                  int follow, char **label)
 {
+       char buf[SMACK_LABEL_LEN + 1];
        char *result;
        ssize_t ret = 0;
 
        ret = follow ?
-               getxattr(path, xattr, NULL, 0) :
-               lgetxattr(path, xattr, NULL, 0);
-       if (ret < 0 && errno != ERANGE)
+               getxattr(path, xattr, buf, SMACK_LABEL_LEN + 1) :
+               lgetxattr(path, xattr, buf, SMACK_LABEL_LEN + 1);
+       if (ret < 0)
                return -1;
 
        result = calloc(ret + 1, 1);
        if (result == NULL)
                return -1;
 
-       ret = follow ?
-               getxattr(path, xattr, result, ret) :
-               lgetxattr(path, xattr, result, ret);
+       ret = get_label(result, buf);
        if (ret < 0) {
                free(result);
                return -1;