File xkbcomp-fix-stack-overflow-when-evaluating-boolean-n.patch of Package libxkbcommon.31860

From 1f9d1248c07cda8aaff762429c0dce146de8632a Mon Sep 17 00:00:00 2001
From: Ran Benita <ran234@gmail.com>
Date: Sat, 10 Mar 2018 23:10:47 +0200
Subject: [PATCH] xkbcomp: fix stack overflow when evaluating boolean negation
Git-commit: 1f9d1248c07cda8aaff762429c0dce146de8632a
Patch-mainline: xkbcommon-0.8.1
References: CVE-2018-15853

The expression evaluator would go into an infinite recursion when
evaluating something like this as a boolean: `!True`. Instead of
recursing to just `True` and negating, it recursed to `!True` itself
again.

Bug inherited from xkbcomp.

Caught with the afl fuzzer.

Signed-off-by: Ran Benita <ran234@gmail.com>

---
 src/xkbcomp/expr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/xkbcomp/expr.c b/src/xkbcomp/expr.c
index 3ff3c18..5d43cba 100644
--- a/src/xkbcomp/expr.c
+++ b/src/xkbcomp/expr.c
@@ -165,7 +165,7 @@ ExprResolveBoolean(struct xkb_context *ctx, const ExprDef *expr,
 
     case EXPR_INVERT:
     case EXPR_NOT:
-        ok = ExprResolveBoolean(ctx, expr, set_rtrn);
+        ok = ExprResolveBoolean(ctx, expr->unary.child, set_rtrn);
         if (ok)
             *set_rtrn = !*set_rtrn;
         return ok;
-- 
2.35.3