Convert newlines to spaces in names written in pg_dump comments.

tglsfdc · tglsfdc · commit 89e0bac86dbc · 2012-02-23T15:53:09.000-05:00
pg_dump was incautious about sanitizing object names that are emitted within SQL comments in its output script. A name containing a newline would at least render the script syntactically incorrect. Maliciously crafted object names could present a SQL injection risk when the script is reloaded. Reported by Heikki Linnakangas, patch by Robert Haas Security: CVE-2012-0868
diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
@@ -99,6 +99,7 @@ static ArchiveHandle *_allocAH(const char *FileSpec, const ArchiveFormat fmt,
 static void _getObjectDescription(PQExpBuffer buf, TocEntry *te,
 					  ArchiveHandle *AH);
 static void _printTocEntry(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt, bool isData, bool acl_pass);
+static char *replace_line_endings(const char *str);
 
 
 static void _doSetFixedOutputState(ArchiveHandle *AH);
@@ -2932,6 +2933,9 @@ _printTocEntry(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt, bool isDat
 	if (!AH->noTocComments)
 	{
 		const char *pfx;
+		char	   *sanitized_name;
+		char	   *sanitized_schema;
+		char	   *sanitized_owner;
 
 		if (isData)
 			pfx = "Data for ";
@@ -2953,12 +2957,39 @@ _printTocEntry(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt, bool isDat
 				ahprintf(AH, "\n");
 			}
 		}
+
+		/*
+		 * Zap any line endings embedded in user-supplied fields, to prevent
+		 * corruption of the dump (which could, in the worst case, present an
+		 * SQL injection vulnerability if someone were to incautiously load a
+		 * dump containing objects with maliciously crafted names).
+		 */
+		sanitized_name = replace_line_endings(te->tag);
+		if (te->namespace)
+			sanitized_schema = replace_line_endings(te->namespace);
+		else
+			sanitized_schema = pg_strdup("-");
+		if (!ropt->noOwner)
+			sanitized_owner = replace_line_endings(te->owner);
+		else
+			sanitized_owner = pg_strdup("-");
+
 		ahprintf(AH, "-- %sName: %s; Type: %s; Schema: %s; Owner: %s",
-				 pfx, te->tag, te->desc,
-				 te->namespace ? te->namespace : "-",
-				 ropt->noOwner ? "-" : te->owner);
+				 pfx, sanitized_name, te->desc, sanitized_schema,
+				 sanitized_owner);
+
+		free(sanitized_name);
+		free(sanitized_schema);
+		free(sanitized_owner);
+
 		if (te->tablespace && !ropt->noTablespace)
-			ahprintf(AH, "; Tablespace: %s", te->tablespace);
+		{
+			char   *sanitized_tablespace;
+
+			sanitized_tablespace = replace_line_endings(te->tablespace);
+			ahprintf(AH, "; Tablespace: %s", sanitized_tablespace);
+			free(sanitized_tablespace);
+		}
 		ahprintf(AH, "\n");
 
 		if (AH->PrintExtraTocPtr !=NULL)
@@ -3053,6 +3084,27 @@ _printTocEntry(ArchiveHandle *AH, TocEntry *te, RestoreOptions *ropt, bool isDat
 	}
 }
 
+/*
+ * Sanitize a string to be included in an SQL comment, by replacing any
+ * newlines with spaces.
+ */
+static char *
+replace_line_endings(const char *str)
+{
+	char   *result;
+	char   *s;
+
+	result = pg_strdup(str);
+
+	for (s = result; *s != '\0'; s++)
+	{
+		if (*s == '\n' || *s == '\r')
+			*s = ' ';
+	}
+
+	return result;
+}
+
 void
 WriteHead(ArchiveHandle *AH)
 {
