From patchwork Wed Jul 12 13:02:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Lu X-Patchwork-Id: 13310370 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 39018EB64D9 for ; Wed, 12 Jul 2023 13:14:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=G1HHJBk/sQvVbiomYqcZlgk1NLXE+A6QfL373AvC8Vo=; b=Uq4iaD3ez8f3tjY24KzlhlXTbq HX4mVndp0mJbC7QlRz6TPQFOElJA2GcE9fQIZ2p4EVgfy/mNWcQbPcZQqnD8tpdh3O+coA9ks75+O jnBLY6ZbYI3xsKqrSC6LsbP7r++XvsNmCv22wbm8juPcFfhGdAvUXkQRNuhx2QchTSlkG56YOxQB3 ChX5jeZNKMjJRMxK/nzRd1IYubYxZmcYQF+ER4T/BzSNzbPrL9tJaAQtdxlWA4HHaSh37rIgqxkZ9 vpUYSHwM6gRTPBbXjaUdAet/2TiK6sXV21eNKhXm9hCnx+FSA+XRXPYC2fG2Buh/iueMtmsIOL+we 3Nj+zYNA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qJZfM-000367-2j; Wed, 12 Jul 2023 13:14:00 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qJZfK-00035b-12 for linux-mediatek@lists.infradead.org; Wed, 12 Jul 2023 13:13:59 +0000 X-UUID: f332d28220b511ee912e1518a6540028-20230712 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=G1HHJBk/sQvVbiomYqcZlgk1NLXE+A6QfL373AvC8Vo=; b=VoYwL7RMiyz/1jncyQ4wWRS+Ueq3h/g5vL9ZdvrXIWaZlD9LU+Ruge2dcgShe2lWebCsmDgGbAjwJBwh95qM+5Hi2Ql+synKKs2EPfBqklREsncTIrmhxe7XMKWmZG1heF4jHUGjmMMCdt2zn3gtihgbXZqbHbTMYFaokjR+4E8=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.28,REQID:f306cbdf-58dc-4663-adae-3643070b1677,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:176cd25,CLOUDID:11a4270e-c22b-45ab-8a43-3004e9216b56,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL:11|1,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR: NO,DKR:0,DKP:0 X-CID-BVR: 0,NGT X-CID-BAS: 0,NGT,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULN X-UUID: f332d28220b511ee912e1518a6540028-20230712 Received: from mtkmbs11n1.mediatek.inc [(172.21.101.185)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 717945414; Wed, 12 Jul 2023 06:13:53 -0700 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Wed, 12 Jul 2023 21:03:16 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 12 Jul 2023 21:03:16 +0800 From: Chris Lu To: Marcel Holtmann , Johan Hedberg , Luiz Von Dentz CC: Sean Wang , Aaron Hou , Steve Lee , linux-bluetooth , linux-kernel , linux-mediatek , Chris Lu Subject: [PATCH v4] Bluetooth: btmtk: Fix null pointer when processing coredump Date: Wed, 12 Jul 2023 21:02:19 +0800 Message-ID: <20230712130218.376-1-chris.lu@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230712_061358_367046_9BD09474 X-CRM114-Status: GOOD ( 10.82 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org There may be a potential null pointer risk if offset value is less than 0 when doing memcmp in btmtk_process_coredump(). Check offset is valid before doing memcmp. Signed-off-by: Chris Lu Co-developed-by: Sean Wang Signed-off-by: Sean Wang --- v2: fix typo v3: fix bot checking error v4: reduce variable 'offset' declaration in v3 --- drivers/bluetooth/btmtk.c | 12 ++++++------ drivers/bluetooth/btmtk.h | 1 + 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c index 786f775196ae..9cc789272ab7 100644 --- a/drivers/bluetooth/btmtk.c +++ b/drivers/bluetooth/btmtk.c @@ -395,12 +395,12 @@ int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb) /* Mediatek coredump data would be more than MTK_COREDUMP_NUM */ if (data->cd_info.cnt > MTK_COREDUMP_NUM && - skb->len > sizeof(MTK_COREDUMP_END) && - !memcmp((char *)&skb->data[skb->len - sizeof(MTK_COREDUMP_END)], - MTK_COREDUMP_END, sizeof(MTK_COREDUMP_END) - 1)) { - bt_dev_info(hdev, "Mediatek coredump end"); - hci_devcd_complete(hdev); - } + skb->len > MTK_COREDUMP_END_LEN) + if (!memcmp((char *)&skb->data[skb->len - MTK_COREDUMP_END_LEN], + MTK_COREDUMP_END, MTK_COREDUMP_END_LEN - 1)) { + bt_dev_info(hdev, "Mediatek coredump end"); + hci_devcd_complete(hdev); + } break; } diff --git a/drivers/bluetooth/btmtk.h b/drivers/bluetooth/btmtk.h index 68309dfe076a..56f5502baadf 100644 --- a/drivers/bluetooth/btmtk.h +++ b/drivers/bluetooth/btmtk.h @@ -24,6 +24,7 @@ #define MTK_COREDUMP_SIZE (1024 * 1000) #define MTK_COREDUMP_END "coredump end" +#define MTK_COREDUMP_END_LEN (sizeof(MTK_COREDUMP_END)) #define MTK_COREDUMP_NUM 255 enum {