From: David Smith <dsmith@redhat.com>
Date: Mon, 16 Apr 2018 21:24:36 +0000 (-0500)
Subject: Fix a small bug in follow_link().
X-Git-Tag: release-3.3~61
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=7df9f1914b90f65ea3d8c64a8ac6dd0469de416e;p=systemtap.git

Fix a small bug in follow_link().

* util.cxx (follow_link): Correctly terminate strings after calling
  readlink().
---

diff --git a/util.cxx b/util.cxx
index 43be61ca0..2e3f4aee2 100644
--- a/util.cxx
+++ b/util.cxx
@@ -460,7 +460,8 @@ follow_link(const string& name, const string& sysroot)
   if (linkname)
     {
       r = readlink(f, linkname, st.st_size + 1);
-      linkname[st.st_size] = '\0';
+      if (r != -1)
+	linkname[r] = '\0';
       /*
        * If we have non-empty sysroot and we got link that
        * points to absolute path name, we need to look at
@@ -487,7 +488,8 @@ follow_link(const string& name, const string& sysroot)
 	      if (linkname)
 		{
 		  r = readlink(f1, linkname, st.st_size + 1);
-		  linkname[st.st_size] = '\0';
+		  if (r != -1)
+		    linkname[r] = '\0';
 		}
 	    }
 	  else