From: John Darrington <john@darrington.wattle.id.au>
Date: Fri, 12 May 2017 10:25:55 +0000 (+0200)
Subject: MEANS: Prevent parser from entering infinite loop.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=eff2701d5d282bfc0c1b52bd2af985705b11b307;p=pspp

MEANS: Prevent parser from entering infinite loop.

Fixes bug #51008
.
---

diff --git a/src/language/stats/means.c b/src/language/stats/means.c
index debb443676..8fa1ba81cd 100644
--- a/src/language/stats/means.c
+++ b/src/language/stats/means.c
@@ -511,23 +511,19 @@ parse_means_table_syntax (struct lexer *lexer, const struct means *cmd, struct m
     return false;
 
   /* Factor variable (s) */
-  while (lex_token (lexer) != T_ENDCMD && lex_token (lexer) != T_SLASH)
+  while (lex_match (lexer, T_BY))
     {
-      if (lex_match (lexer, T_BY))
-	{
-	  table->n_layers++;
-          table->layers =
-	    pool_realloc (cmd->pool, table->layers,
-			  sizeof (*table->layers) * table->n_layers);
-
-	  if (!parse_variables_const_pool
-              (lexer, cmd->pool, cmd->dict,
-               &table->layers[table->n_layers - 1].factor_vars,
-               &table->layers[table->n_layers - 1].n_factor_vars,
-               PV_NO_DUPLICATE))
-	    return false;
-
-	}
+      table->n_layers++;
+      table->layers =
+	pool_realloc (cmd->pool, table->layers,
+		      sizeof (*table->layers) * table->n_layers);
+
+      if (!parse_variables_const_pool
+	  (lexer, cmd->pool, cmd->dict,
+	   &table->layers[table->n_layers - 1].factor_vars,
+	   &table->layers[table->n_layers - 1].n_factor_vars,
+	   PV_NO_DUPLICATE))
+	return false;
     }
 
   /* There is always at least one layer.
diff --git a/tests/language/stats/means.at b/tests/language/stats/means.at
index 56ab455ba8..0d990f85b1 100644
--- a/tests/language/stats/means.at
+++ b/tests/language/stats/means.at
@@ -570,4 +570,26 @@ MEANS TABLES =  outcome
 
 AT_CHECK([pspp -O format=csv means-bad.sps], [1], [ignore])
 
-AT_CLEANUP
\ No newline at end of file
+AT_CLEANUP
+
+
+
+AT_SETUP([MEANS parser bug])
+
+dnl This bug caused an infinite loop
+AT_DATA([means-bad.sps], [dnl
+DATA LIST notable LIST /a1 a2 a3 a4 a5 a6 a7 a8 a9 a10 fylo *.
+begin data.
+1 2 3 4 5 6 7 8 9 0 11
+end data.
+
+MEANS TABLES = a1 a2 a3 a4 a5 a6 a7 a8 a9 a10a BY fylo.
+])
+
+AT_CHECK([pspp -O format=csv means-bad.sps], [1], [ignore])
+
+AT_CLEANUP
+
+
+
+