Don't downcase entries within shared_preload_libraries et al.

tglsfdc · tglsfdc · commit a69dfe5f40f7 · 2017-06-20T13:03:29.000-04:00
load_libraries(), which processes the various xxx_preload_libraries GUCs, was parsing them using SplitIdentifierString() which isn't really appropriate for values that could be path names: it downcases unquoted text, and it doesn't allow embedded whitespace unless quoted. Use SplitDirectoriesString() instead. That also allows us to simplify load_libraries() a bit, since canonicalize_path() is now done for it. While this definitely seems like a bug fix, it has the potential to break configuration settings that accidentally worked before because of the downcasing behavior. Also, there's an easy workaround for the bug, namely to double-quote troublesome text. Hence, no back-patch. QL Zhuo, tweaked a bit by me Discussion: https://postgr.es/m/CAB-oJtxHVDc3H+Km3CjB9mY1VDzuyaVH_ZYSz7iXcRqCtb93Ew@mail.gmail.com
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
@@ -3347,7 +3347,9 @@ SplitIdentifierString(char *rawstring, char separator,
 
 
 /*
- * SplitDirectoriesString --- parse a string containing directory names
+ * SplitDirectoriesString --- parse a string containing file/directory names
+ *
+ * This works fine on file names too; the function name is historical.
  *
  * This is similar to SplitIdentifierString, except that the parsing
  * rules are meant to handle pathnames instead of identifiers: there is
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
@@ -1435,12 +1435,12 @@ load_libraries(const char *libraries, const char *gucname, bool restricted)
 	/* Need a modifiable copy of string */
 	rawstring = pstrdup(libraries);
 
-	/* Parse string into list of identifiers */
-	if (!SplitIdentifierString(rawstring, ',', &elemlist))
+	/* Parse string into list of filename paths */
+	if (!SplitDirectoriesString(rawstring, ',', &elemlist))
 	{
 		/* syntax error in list */
+		list_free_deep(elemlist);
 		pfree(rawstring);
-		list_free(elemlist);
 		ereport(LOG,
 				(errcode(ERRCODE_SYNTAX_ERROR),
 				 errmsg("invalid list syntax in parameter \"%s\"",
@@ -1450,28 +1450,25 @@ load_libraries(const char *libraries, const char *gucname, bool restricted)
 
 	foreach(l, elemlist)
 	{
-		char	   *tok = (char *) lfirst(l);
-		char	   *filename;
+		/* Note that filename was already canonicalized */
+		char	   *filename = (char *) lfirst(l);
+		char	   *expanded = NULL;
 
-		filename = pstrdup(tok);
-		canonicalize_path(filename);
 		/* If restricting, insert $libdir/plugins if not mentioned already */
 		if (restricted && first_dir_separator(filename) == NULL)
 		{
-			char	   *expanded;
-
 			expanded = psprintf("$libdir/plugins/%s", filename);
-			pfree(filename);
 			filename = expanded;
 		}
 		load_file(filename, restricted);
 		ereport(DEBUG1,
 				(errmsg("loaded library \"%s\"", filename)));
-		pfree(filename);
+		if (expanded)
+			pfree(expanded);
 	}
 
+	list_free_deep(elemlist);
 	pfree(rawstring);
-	list_free(elemlist);
 }
 
 /*

Original file line number	Diff line number	Diff line change
`@@ -3347,7 +3347,9 @@ SplitIdentifierString(char *rawstring, char separator,`
`3347`	`3347`
`3348`	`3348`
`3349`	`3349`	`/*`
`3350`		`- * SplitDirectoriesString --- parse a string containing directory names`
	`3350`	`+ * SplitDirectoriesString --- parse a string containing file/directory names`
	`3351`	`+ *`
	`3352`	`+ * This works fine on file names too; the function name is historical.`
`3351`	`3353`	`*`
`3352`	`3354`	`* This is similar to SplitIdentifierString, except that the parsing`
`3353`	`3355`	`* rules are meant to handle pathnames instead of identifiers: there is`