From patchwork Wed Jul 12 03:32:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Lu X-Patchwork-Id: 13309547 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 54695EB64DA for ; Wed, 12 Jul 2023 03:33:50 +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=h1TvgYKK/BgP/Zs3BnMxPOKxtFdPPOngjd+lZMmZK74=; b=daR3OEnvoJXjR550phKiFROPse 0I2n5GGnpIaA5BELcIsdoXejNe9J9aNFcdIzfEM1k1u/Xk763IkwXnlp3xi+uSOXcjYfHCrANEdmi Pa1bRSiAc0AcKlhiPB1/EGfLS1BR2/zlT9xG0TH9X7qvUPO4+p0dhTxMIq1Ay8sI30MHn8NglJ4kx +Dt8h69+rmp+3gz8fZSH8apV7ZeP1rQuX8j67F/IN659VhEmWJGfpI0r3f7KTUvA/QjcvD7GIPhnR e1je2+PmPgZPF6pCbAPVxaY3aVmAOtlws8twHEHttoCgRpByMvPs2VlVSNoEinlZC/mnYUdqFRdfV P6X19vyw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qJQbn-00GP1q-1m; Wed, 12 Jul 2023 03:33:43 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qJQbl-00GP0o-0g for linux-mediatek@lists.infradead.org; Wed, 12 Jul 2023 03:33:42 +0000 X-UUID: df6242c0206411ee83ed1395ce914268-20230711 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=h1TvgYKK/BgP/Zs3BnMxPOKxtFdPPOngjd+lZMmZK74=; b=FJyOoFVeMwP8PFQz6tWEu+JQJ5kM5k0w+o2PoOaUcORuCpgOYwY/WaL3SI/1HjAbIwaslVcZ78IpJNqzIb+76xd87N+EnjB1c8TiKWdhKWYf6uue/H3jBPlM63hDYMwcqW3RQv4WM70cz9bFVcOoUzm0+Uc8UOOOFsWWmkW6Pww=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.28,REQID:bfd4c15d-1d0c-45af-a9b5-507dcd009a79,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:5e632168-314d-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: df6242c0206411ee83ed1395ce914268-20230711 Received: from mtkmbs13n2.mediatek.inc [(172.21.101.108)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1732412766; Tue, 11 Jul 2023 20:33:31 -0700 Received: from mtkmbs13n1.mediatek.inc (172.21.101.193) by mtkmbs11n1.mediatek.inc (172.21.101.185) 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 11:32:57 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs13n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 12 Jul 2023 11:32:57 +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] Bluetooth: btmtk: Fix null pointer when processing coredump Date: Wed, 12 Jul 2023 11:32:30 +0800 Message-ID: <20230712033229.12339-1-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-20230711_203341_255705_AD05330D X-CRM114-Status: GOOD ( 12.50 ) 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(). Checking offset is valid before doing memcmp. Signed-off-by: Chris Lu Co-developed-by: Sean Wang --- 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..9ae46b4c98b9 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.dump_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; }