diff --git a/lib/openpam_set_option.c b/lib/openpam_set_option.c
index b41c3f9..cd8271d 100644
--- a/lib/openpam_set_option.c
+++ b/lib/openpam_set_option.c
@@ -31,7 +31,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $P4: //depot/projects/openpam/lib/openpam_set_option.c#10 $
+ * $P4: //depot/projects/openpam/lib/openpam_set_option.c#11 $
  */
 
 #include <sys/param.h>
@@ -82,9 +82,8 @@ openpam_set_option(pam_handle_t *pamh,
 		cur->optv[i] = NULL;
 		RETURNC(PAM_SUCCESS);
 	}
-	if ((opt = malloc(len + strlen(value) + 2)) == NULL)
+	if (asprintf(&opt, "%.*s=%s", (int)len, option, value) < 0)
 		RETURNC(PAM_BUF_ERR);
-	sprintf(opt, "%.*s=%s", (int)len, option, value);
 	if (i == cur->optc) {
 		/* add */
 		optv = realloc(cur->optv, sizeof(char *) * (cur->optc + 2));
diff --git a/lib/pam_setenv.c b/lib/pam_setenv.c
index 1d47422..02ffe23 100644
--- a/lib/pam_setenv.c
+++ b/lib/pam_setenv.c
@@ -31,7 +31,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $P4: //depot/projects/openpam/lib/pam_setenv.c#9 $
+ * $P4: //depot/projects/openpam/lib/pam_setenv.c#10 $
  */
 
 #include <stdlib.h>
@@ -71,9 +71,8 @@ pam_setenv(pam_handle_t *pamh,
 		RETURNC(PAM_SUCCESS);
 
 	/* set it... */
-	if ((env = malloc(strlen(name) + strlen(value) + 2)) == NULL)
+	if (asprintf(&env, "%s=%s", name, value) < 0)
 		RETURNC(PAM_BUF_ERR);
-	sprintf(env, "%s=%s", name, value);
 	r = pam_putenv(pamh, env);
 	FREE(env);
 	RETURNC(r);