1 files changed, 22 insertions, 20 deletions

diff --git a/xdiff/xmerge.c b/xdiff/xmerge.c
index fff0b59..af40c88 100644
--- a/xdiff/xmerge.c
+++ b/xdiff/xmerge.c
@@ -684,42 +684,42 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1,
 int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
 		xmparam_t const *xmp, mmbuffer_t *result)
 {
-	xdchange_t *xscr1, *xscr2;
+	xdchange_t *xscr1 = NULL, *xscr2 = NULL;
 	xdfenv_t xe1, xe2;
-	int status;
+	int status = -1;
 	xpparam_t const *xpp = &xmp->xpp;
 
 	result->ptr = NULL;
 	result->size = 0;
 
-	if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0) {
+	if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0)
 		return -1;
-	}
-	if (xdl_do_diff(orig, mf2, xpp, &xe2) < 0) {
-		xdl_free_env(&xe1);
-		return -1;
-	}
+
+	if (xdl_do_diff(orig, mf2, xpp, &xe2) < 0)
+		goto free_xe1; /* avoid double free of xe2 */
+
 	if (xdl_change_compact(&xe1.xdf1, &xe1.xdf2, xpp->flags) < 0 ||
 	    xdl_change_compact(&xe1.xdf2, &xe1.xdf1, xpp->flags) < 0 ||
-	    xdl_build_script(&xe1, &xscr1) < 0) {
-		xdl_free_env(&xe1);
-		return -1;
-	}
+	    xdl_build_script(&xe1, &xscr1) < 0)
+		goto out;
+
 	if (xdl_change_compact(&xe2.xdf1, &xe2.xdf2, xpp->flags) < 0 ||
 	    xdl_change_compact(&xe2.xdf2, &xe2.xdf1, xpp->flags) < 0 ||
-	    xdl_build_script(&xe2, &xscr2) < 0) {
-		xdl_free_script(xscr1);
-		xdl_free_env(&xe1);
-		xdl_free_env(&xe2);
-		return -1;
-	}
-	status = 0;
+	    xdl_build_script(&xe2, &xscr2) < 0)
+		goto out;
+
 	if (!xscr1) {
 		result->ptr = xdl_malloc(mf2->size);
+		if (!result->ptr)
+			goto out;
+		status = 0;
 		memcpy(result->ptr, mf2->ptr, mf2->size);
 		result->size = mf2->size;
 	} else if (!xscr2) {
 		result->ptr = xdl_malloc(mf1->size);
+		if (!result->ptr)
+			goto out;
+		status = 0;
 		memcpy(result->ptr, mf1->ptr, mf1->size);
 		result->size = mf1->size;
 	} else {
@@ -727,11 +727,13 @@ int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
 				      &xe2, xscr2,
 				      xmp, result);
 	}
+ out:
 	xdl_free_script(xscr1);
 	xdl_free_script(xscr2);
 
-	xdl_free_env(&xe1);
 	xdl_free_env(&xe2);
+ free_xe1:
+	xdl_free_env(&xe1);
 
 	return status;
 }