From patchwork Thu Nov 9 17:15:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13451571 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 7FA6EC4332F for ; Thu, 9 Nov 2023 17:16:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r18dH-0000rT-Ay; Thu, 09 Nov 2023 12:15:55 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r18d6-0000mM-Pn; Thu, 09 Nov 2023 12:15:47 -0500 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r18d1-0007L0-PM; Thu, 09 Nov 2023 12:15:43 -0500 Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4SR7rQ2yF8z4xVK; Fri, 10 Nov 2023 04:15:34 +1100 (AEDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4SR7rM3Ykcz4xVl; Fri, 10 Nov 2023 04:15:31 +1100 (AEDT) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Cc: =?utf-8?b?RnLDqWTDqXJpYyBCYXJyYXQ=?= , Nicholas Piggin , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Peter Maydell , =?utf-8?q?C=C3=A9dric_Le_Goater?= , Glenn Miles Subject: [PATCH v2] ppc/pnv: Fix potential overflow in I2C model Date: Thu, 9 Nov 2023 18:15:25 +0100 Message-ID: <20231109171525.1129353-1-clg@kaod.org> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=uA+F=GW=kaod.org=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Coverity warns that "i2c_bus_busy(i2c->busses[i]) << i" might overflow because the expression is evaluated using 32-bit arithmetic and then used in a context expecting a uint64_t. While we are at it, introduce a PNV_I2C_MAX_BUSSES constant and check the number of busses at realize time. Fixes: Coverity CID 1523918 Cc: Glenn Miles Signed-off-by: Cédric Le Goater Reviewed-by: Glenn Miles Reviewed-by: Philippe Mathieu-Daudé --- v2: - check PNV_I2C_MAX_BUSSES in realize - removed extra space before cast. hw/ppc/pnv_i2c.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/hw/ppc/pnv_i2c.c b/hw/ppc/pnv_i2c.c index f75e59e70977..483d91d15a77 100644 --- a/hw/ppc/pnv_i2c.c +++ b/hw/ppc/pnv_i2c.c @@ -151,6 +151,7 @@ #define I2C_RESET_S_SDA_REG 0x11 #define PNV_I2C_FIFO_SIZE 8 +#define PNV_I2C_MAX_BUSSES 64 static I2CBus *pnv_i2c_get_bus(PnvI2C *i2c) { @@ -437,7 +438,7 @@ static uint64_t pnv_i2c_xscom_read(void *opaque, hwaddr addr, case I2C_PORT_BUSY_REG: /* compute busy bit for each port */ val = 0; for (i = 0; i < i2c->num_busses; i++) { - val |= i2c_bus_busy(i2c->busses[i]) << i; + val |= (uint64_t)i2c_bus_busy(i2c->busses[i]) << i; } break; @@ -641,6 +642,11 @@ static void pnv_i2c_realize(DeviceState *dev, Error **errp) assert(i2c->chip); + if (i2c->num_busses > PNV_I2C_MAX_BUSSES) { + error_setg(errp, "Invalid number of busses: %u", i2c->num_busses); + return; + } + pnv_xscom_region_init(&i2c->xscom_regs, OBJECT(i2c), &pnv_i2c_xscom_ops, i2c, "xscom-i2c", PNV9_XSCOM_I2CM_SIZE);