From: Matthew Fernandez <matthew.fernandez@gmail.com>
Date: Sun, 13 Sep 2020 03:24:54 +0000 (-0700)
Subject: fix resource leakage in unflatten
X-Git-Tag: 2.46.0~20^2^2~73^2~1
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=197460f985bf06970a939a4fdbffb9b8e8a1261c;p=graphviz

fix resource leakage in unflatten

This addresses the following Coverity warning:

  Error: RESOURCE_LEAK (CWE-772): [#def70]
  graphviz-2.40.1/cmd/tools/unflatten.c:195: alloc_fn: Storage is returned from allocation function "openFile".
  graphviz-2.40.1/cmd/tools/unflatten.c:160:5: alloc_fn: Storage is returned from allocation function "fopen".
  graphviz-2.40.1/cmd/tools/unflatten.c:160:5: var_assign: Assigning: "fp" = "fopen(name, mode)".
  graphviz-2.40.1/cmd/tools/unflatten.c:170:5: return_alloc: Returning allocated memory "fp".
  graphviz-2.40.1/cmd/tools/unflatten.c:195: var_assign: Assigning: "outFile" = storage returned from "openFile(optarg, "w")".
  graphviz-2.40.1/cmd/tools/unflatten.c:195: overwrite_var: Overwriting "outFile" in "outFile = openFile(optarg, "w")" leaks the storage that "outFile" points to.
  #  193|         break;
  #  194|     case 'o':
  #  195|->       outFile = openFile(optarg, "w");
  #  196|         break;
  #  197|     case '?':

Related to #1464.
---

diff --git a/cmd/tools/unflatten.c b/cmd/tools/unflatten.c
index 9658f51c1..d65d2d304 100644
--- a/cmd/tools/unflatten.c
+++ b/cmd/tools/unflatten.c
@@ -187,6 +187,8 @@ static char **scanargs(int argc, char **argv)
 		ChainLimit = ival;
 	    break;
 	case 'o':
+	    if (outFile != NULL)
+		fclose(outFile);
 	    outFile = openFile(optarg, "w");
 	    break;
 	case '?':