From patchwork Wed Mar 17 23:02:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mark Cave-Ayland X-Patchwork-Id: 1455033 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4F15P52rD0z9sVm for ; Thu, 18 Mar 2021 10:06:01 +1100 (AEDT) Received: from localhost ([::1]:47262 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lMfEl-0004m6-Ea for incoming@patchwork.ozlabs.org; Wed, 17 Mar 2021 19:05:59 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43496) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMfBc-0002Gv-0p for qemu-devel@nongnu.org; Wed, 17 Mar 2021 19:02:44 -0400 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]:35380 helo=mail.default.ilande.uk0.bigv.io) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMfBa-0005MH-Ep for qemu-devel@nongnu.org; Wed, 17 Mar 2021 19:02:43 -0400 Received: from host86-148-103-84.range86-148.btcentralplus.com ([86.148.103.84] helo=kentang.home) by mail.default.ilande.uk0.bigv.io with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lMfBZ-0006Bn-Kh; Wed, 17 Mar 2021 23:02:46 +0000 From: Mark Cave-Ayland To: qemu-devel@nongnu.org, alxndr@bu.edu, laurent@vivier.eu, pbonzini@redhat.com Date: Wed, 17 Mar 2021 23:02:19 +0000 Message-Id: <20210317230223.24854-3-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210317230223.24854-1-mark.cave-ayland@ilande.co.uk> References: <20210317230223.24854-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 86.148.103.84 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH v2 2/6] esp: don't overflow cmdfifo if TC is larger than the cmdfifo size 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.uk0.bigv.io) Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.default.ilande.uk0.bigv.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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" If a guest transfers the message out/command phase data using DMA with a TC that is larger than the cmdfifo size then the cmdfifo overflows triggering an assert. Limit the size of the transfer to the free space available in cmdfifo. Buglink: https://bugs.launchpad.net/qemu/+bug/1919036 Signed-off-by: Mark Cave-Ayland Reviewed-by: Philippe Mathieu-Daudé Tested-by: Alexander Bulekov --- hw/scsi/esp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c index 5d3f1ccbc8..bbcbfa4a91 100644 --- a/hw/scsi/esp.c +++ b/hw/scsi/esp.c @@ -579,6 +579,7 @@ static void esp_do_dma(ESPState *s) cmdlen = fifo8_num_used(&s->cmdfifo); trace_esp_do_dma(cmdlen, len); if (s->dma_memory_read) { + len = MIN(len, fifo8_num_free(&s->cmdfifo)); s->dma_memory_read(s->dma_opaque, buf, len); fifo8_push_all(&s->cmdfifo, buf, len); } else {