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From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Jiri Slaby <jslaby@suse.cz>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH AUTOSEL 5.4 03/40] vt/consolemap: do font sum unsigned
Date:   Wed, 24 Feb 2021 07:53:03 -0500
Message-Id: <20210224125340.483162-3-sashal@kernel.org>
In-Reply-To: <20210224125340.483162-1-sashal@kernel.org>
References: <20210224125340.483162-1-sashal@kernel.org>
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From: Jiri Slaby <jslaby@suse.cz>

[ Upstream commit 9777f8e60e718f7b022a94f2524f967d8def1931 ]

The constant 20 makes the font sum computation signed which can lead to
sign extensions and signed wraps. It's not much of a problem as we build
with -fno-strict-overflow. But if we ever decide not to, be ready, so
switch the constant to unsigned.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210105120239.28031-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/vt/consolemap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c
index b28aa0d289f89..251c02af1fc3e 100644
--- a/drivers/tty/vt/consolemap.c
+++ b/drivers/tty/vt/consolemap.c
@@ -495,7 +495,7 @@ con_insert_unipair(struct uni_pagedir *p, u_short unicode, u_short fontpos)
 
 	p2[unicode & 0x3f] = fontpos;
 	
-	p->sum += (fontpos << 20) + unicode;
+	p->sum += (fontpos << 20U) + unicode;
 
 	return 0;
 }
-- 
2.27.0