From: Andrew Deason <adeason@sinenomine.net>
Date: Thu, 24 May 2012 19:53:59 +0000 (-0500)
Subject: cmd: Avoid premature OptionAsString free
X-Git-Tag: upstream/1.8.0_pre1^2~2320
X-Git-Url: https://git.michaelhowe.org/gitweb/?a=commitdiff_plain;h=e1ff7148cce62f7c34614dc1ac1edc909dea1c55;p=packages%2Fo%2Fopenafs.git

cmd: Avoid premature OptionAsString free

Only free the previously-set string value if we're actually going to
change it. This avoids the scenario where a caller does something
like:

  char *str = strdup("defaultval");
  /* ... */
  cmd_OptionAsString(as, OPT_foo, &str);

resulting in 'str' pointing to freed memory when the relevant option
is not specified, or there is some other error.

Change-Id: If1f94d5eb39cc4dba9a4195ff20850ff81737eb9
Reviewed-on: http://gerrit.openafs.org/7475
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---

diff --git a/src/cmd/cmd.c b/src/cmd/cmd.c
index 903dc94dc..1c5786ee8 100644
--- a/src/cmd/cmd.c
+++ b/src/cmd/cmd.c
@@ -1358,9 +1358,6 @@ cmd_OptionAsString(struct cmd_syndesc *syn, int pos, char **value)
     const char *str;
     int code;
 
-    if (*value)
-	free(*value);
-
     code = _get_config_string(syn, pos, &str);
     if (code)
 	return code;
@@ -1368,6 +1365,8 @@ cmd_OptionAsString(struct cmd_syndesc *syn, int pos, char **value)
     if (str == NULL)
 	return CMD_MISSING;
 
+    if (*value)
+	free(*value);
     *value = strdup(str);
 
     return 0;