From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:37584 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732817AbeKLIS2 (ORCPT ); Mon, 12 Nov 2018 03:18:28 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.19 293/361] media: v4l2-tpg: fix kernel oops when enabling HFLIP and OSD Date: Sun, 11 Nov 2018 14:20:40 -0800 Message-Id: <20181111221656.858224392@linuxfoundation.org> In-Reply-To: <20181111221619.915519183@linuxfoundation.org> References: <20181111221619.915519183@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hans Verkuil commit 250854eed5d45a73d81e4137dfd85180af6f2ec3 upstream. When the OSD is on (i.e. vivid displays text on top of the test pattern), and you enable hflip, then the driver crashes. The cause turned out to be a division of a negative number by an unsigned value. You expect that -8 / 2U would be -4, but in reality it is 2147483644 :-( Fixes: 3e14e7a82c1ef ("vivid-tpg: add hor/vert downsampling support to tpg_gen_text") Signed-off-by: Hans Verkuil Reported-by: Mauro Carvalho Chehab Cc: # for v4.1 and up Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c @@ -1770,7 +1770,7 @@ typedef struct { u16 __; u8 _; } __packe pos[7] = (chr & (0x01 << 0) ? fg : bg); \ } \ \ - pos += (tpg->hflip ? -8 : 8) / hdiv; \ + pos += (tpg->hflip ? -8 : 8) / (int)hdiv; \ } \ } \ } while (0)