From nobody Wed Feb 11 03:44:21 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1633383414482672.3719979040546; Mon, 4 Oct 2021 14:36:54 -0700 (PDT) Received: from localhost ([::1]:49876 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mXVdl-000320-FC for importer@patchew.org; Mon, 04 Oct 2021 17:36:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56790) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXVNI-0001Po-BS for qemu-devel@nongnu.org; Mon, 04 Oct 2021 17:19:52 -0400 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]:35842 helo=mail.default.ilande.bv.iomart.io) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mXVNH-00021U-1w for qemu-devel@nongnu.org; Mon, 04 Oct 2021 17:19:52 -0400 Received: from [2a00:23c4:8b9d:4100:5d98:71b5:90ca:dad1] (helo=kentang.home) by mail.default.ilande.bv.iomart.io with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mXVN2-0008kv-4Y; Mon, 04 Oct 2021 22:19:40 +0100 From: Mark Cave-Ayland To: qemu-devel@nongnu.org, laurent@vivier.eu Date: Mon, 4 Oct 2021 22:19:19 +0100 Message-Id: <20211004211928.15803-4-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20211004211928.15803-1-mark.cave-ayland@ilande.co.uk> References: <20211004211928.15803-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 2a00:23c4:8b9d:4100:5d98:71b5:90ca:dad1 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH v2 03/12] macfb: fix overflow of color_palette array X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.default.ilande.bv.iomart.io) Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.default.ilande.bv.iomart.io X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZM-MESSAGEID: 1633383416689100001 Content-Type: text/plain; charset="utf-8" The palette_current index counter has a maximum size of 256 * 3 to cover a = full color palette of 256 RGB entries. Linux assumes that the palette_current in= dex wraps back around to zero after writing 256 RGB entries so ensure that palette_current is reset at this point to prevent data corruption within MacfbState. Signed-off-by: Mark Cave-Ayland Reviewed-by: Laurent Vivier --- hw/display/macfb.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/hw/display/macfb.c b/hw/display/macfb.c index b363bab889..39dab49026 100644 --- a/hw/display/macfb.c +++ b/hw/display/macfb.c @@ -303,7 +303,9 @@ static void macfb_ctrl_write(void *opaque, s->palette_current =3D 0; break; case DAFB_LUT: - s->color_palette[s->palette_current++] =3D val; + s->color_palette[s->palette_current] =3D val; + s->palette_current =3D (s->palette_current + 1) % + ARRAY_SIZE(s->color_palette); if (s->palette_current % 3) { macfb_invalidate_display(s); } --=20 2.20.1