From patchwork Fri Mar 21 09:25:58 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jamin Lin X-Patchwork-Id: 14025059 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 45278C35FFF for ; Fri, 21 Mar 2025 09:27:10 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tvYeK-0006Ju-U7; Fri, 21 Mar 2025 05:26:45 -0400 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 1tvYeF-0006Dv-TD; Fri, 21 Mar 2025 05:26:39 -0400 Received: from mail.aspeedtech.com ([211.20.114.72] helo=TWMBX01.aspeed.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tvYeD-00056F-Rp; Fri, 21 Mar 2025 05:26:39 -0400 Received: from TWMBX01.aspeed.com (192.168.0.62) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.12; Fri, 21 Mar 2025 17:26:24 +0800 Received: from mail.aspeedtech.com (192.168.10.10) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server id 15.2.1258.12 via Frontend Transport; Fri, 21 Mar 2025 17:26:24 +0800 To: =?utf-8?q?C=C3=A9dric_Le_Goater?= , Peter Maydell , Steven Lee , Troy Lee , Andrew Jeffery , "Joel Stanley" , Fabiano Rosas , Laurent Vivier , Paolo Bonzini , "open list:ASPEED BMCs" , "open list:All patches CC here" CC: , Subject: [PATCH v1 02/22] hw/misc/aspeed_hace: Fix buffer overflow in has_padding function Date: Fri, 21 Mar 2025 17:25:58 +0800 Message-ID: <20250321092623.2097234-3-jamin_lin@aspeedtech.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250321092623.2097234-1-jamin_lin@aspeedtech.com> References: <20250321092623.2097234-1-jamin_lin@aspeedtech.com> MIME-Version: 1.0 Received-SPF: pass client-ip=211.20.114.72; envelope-from=jamin_lin@aspeedtech.com; helo=TWMBX01.aspeed.com 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, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_FAIL=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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jamin Lin X-Patchwork-Original-From: Jamin Lin via From: Jamin Lin Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The maximum padding size is either 64 or 128 bytes and should always be smaller than "req_len". If "padding_size" exceeds "req_len", then "req_len - padding_size" underflows due to "uint32_t" data type, leading to a large incorrect value (e.g., `0xFFXXXXXX`). This causes an out-of-bounds memory access, potentially leading to a buffer overflow. Added a check to ensure "padding_size" does not exceed "req_len" before computing "pad_offset". This prevents "req_len - padding_size" from underflowing and avoids accessing invalid memory. Signed-off-by: Jamin Lin Reviewed-by: Cédric Le Goater --- hw/misc/aspeed_hace.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/hw/misc/aspeed_hace.c b/hw/misc/aspeed_hace.c index 8e7e8113a5..d8b5f048bb 100644 --- a/hw/misc/aspeed_hace.c +++ b/hw/misc/aspeed_hace.c @@ -128,6 +128,11 @@ static bool has_padding(AspeedHACEState *s, struct iovec *iov, if (*total_msg_len <= s->total_req_len) { uint32_t padding_size = s->total_req_len - *total_msg_len; uint8_t *padding = iov->iov_base; + + if (padding_size > req_len) { + return false; + } + *pad_offset = req_len - padding_size; if (padding[*pad_offset] == 0x80) { return true;