From 6495bca92e08000b1a5ad95f9db4ef62b746bebf Mon Sep 17 00:00:00 2001
From: Phil Sutter <phil@nwl.cc>
Date: Thu, 29 Nov 2018 13:20:37 +0100
Subject: [PATCH] ssfilter: Fix for inverted last expression

When fixing for shift/reduce conflicts, possibility to invert the last
expression by prefixing with '!' or 'not' was accidentally removed.

Fix this by allowing for expr to be an inverted expr so that any
reference to it in exprlist accepts the inverted prefix.

Reported-by: Eric Dumazet <edumazet@google.com>
Fixes: b2038cc0b2403 ("ssfilter: Eliminate shift/reduce conflicts")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 misc/ssfilter.y | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/misc/ssfilter.y b/misc/ssfilter.y
index 0413ddda..a901ae75 100644
--- a/misc/ssfilter.y
+++ b/misc/ssfilter.y
@@ -54,10 +54,6 @@ null:   /* NOTHING */ { $$ = NULL; }
         ;
 
 exprlist: expr
-        | '!' expr
-        {
-                $$ = alloc_node(SSF_NOT, $2);
-        }
         | exprlist '|' expr
         {
                 $$ = alloc_node(SSF_OR, $1);
@@ -83,6 +79,10 @@ expr:	'(' exprlist ')'
 	{
 		$$ = $2;
 	}
+	| '!' expr
+	{
+		$$ = alloc_node(SSF_NOT, $2);
+	}
 	| DCOND eq HOSTCOND
         {
 		$$ = alloc_node(SSF_DCOND, $3);