From patchwork Wed Jul 12 03:42:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Lu X-Patchwork-Id: 701944 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD0BAEB64D9 for ; Wed, 12 Jul 2023 03:43:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231472AbjGLDm7 (ORCPT ); Tue, 11 Jul 2023 23:42:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231891AbjGLDmy (ORCPT ); Tue, 11 Jul 2023 23:42:54 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27F0E1993; Tue, 11 Jul 2023 20:42:48 -0700 (PDT) X-UUID: 29aa525e206611ee9cb5633481061a41-20230712 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=Q0lPk1iLgS+gEIQ4yquVahBU2BVhM8ZZVKXYZevB4ws=; b=NRMtfKe+GUuA+tsAoTeU+7v6zEZGLP1sehVZtSps9ehspZGG6D0buvRgz8gjeJLGtm0lEWqqulL/cmr16p7BB2hurIvGlY2EYAtAigLnOtohboH3jdLqmd0Chy8khWLPu0ZpgfF5x8FNTZEvg6f0kEib9eyyo34OfKQiocvvdNg=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.28, REQID:57b565cb-eece-4f2c-b695-4f642bf55cd5, 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:c37c2168-314d-4083-81b6-6a74159151eb, 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: 29aa525e206611ee9cb5633481061a41-20230712 Received: from mtkmbs10n2.mediatek.inc [(172.21.101.183)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 139301063; Wed, 12 Jul 2023 11:42:45 +0800 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by MTKMBS14N1.mediatek.inc (172.21.101.75) 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 11:42:43 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 12 Jul 2023 11:42:43 +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 v2] Bluetooth: btmtk: Fix null pointer when processing coredump Date: Wed, 12 Jul 2023 11:42:07 +0800 Message-ID: <20230712034206.12484-1-chris.lu@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org There may be a potential null pointer risk if offset value is less than 0 when doing memcmp in btmtk_process_coredump(). Checking offset is valid before doing memcmp. Signed-off-by: Chris Lu Co-developed-by: Sean Wang --- v2: fix typo --- drivers/bluetooth/btmtk.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c index 786f775196ae..0f290430ae0e 100644 --- a/drivers/bluetooth/btmtk.c +++ b/drivers/bluetooth/btmtk.c @@ -370,7 +370,7 @@ EXPORT_SYMBOL_GPL(btmtk_register_coredump); int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb) { struct btmediatek_data *data = hci_get_priv(hdev); - int err; + int err, offset; if (!IS_ENABLED(CONFIG_DEV_COREDUMP)) return 0; @@ -392,15 +392,15 @@ int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb) if (err < 0) break; data->cd_info.cnt++; + offset = skb->len - sizeof(MTK_COREDUMP_END); /* 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); - } + if (data->cd_info.cnt > MTK_COREDUMP_NUM && offset > 0) + if (!memcmp((char *)&skb->data[offset], MTK_COREDUMP_END, + sizeof(MTK_COREDUMP_END) - 1)) { + bt_dev_info(hdev, "Mediatek coredump end"); + hci_devcd_complete(hdev); + } break; }