From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5C8FC433DB for ; Thu, 25 Feb 2021 16:02:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 962C164ED3 for ; Thu, 25 Feb 2021 16:02:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233383AbhBYQC6 (ORCPT ); Thu, 25 Feb 2021 11:02:58 -0500 Received: from m42-2.mailgun.net ([69.72.42.2]:24573 "EHLO m42-2.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229886AbhBYQCn (ORCPT ); Thu, 25 Feb 2021 11:02:43 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1614268942; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=x99euNNRJLLgAM+BgTQQDetLzkrbH3jmkzxNTvi0kBk=; b=mmtJwWeXtJ3Sbe96eXk5BavEQOMNnYBFFXdOu0XO+Qp8E72gwmC4LQBkE/DDexDuDxqEn4eH HHyaTZgZzF+V/bxgiEH8NMJhh7fEZX8pXmjK6JsBRI7LkbL32/vxrqDDB+aZ+oEPyQ+AgzIJ qC4UX2aLiLAhQFaHtDv8lTRlzu4= X-Mailgun-Sending-Ip: 69.72.42.2 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n05.prod.us-west-2.postgun.com with SMTP id 6037c9abba1dc157804c2b20 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 25 Feb 2021 16:00:43 GMT Sender: mojha=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 8DB7AC43463; Thu, 25 Feb 2021 16:00:43 +0000 (UTC) Received: from mojha-linux.qualcomm.com (unknown [202.46.22.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mojha) by smtp.codeaurora.org (Postfix) with ESMTPSA id 1DCC2C433C6; Thu, 25 Feb 2021 16:00:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 1DCC2C433C6 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=mojha@codeaurora.org From: Mukesh Ojha To: linux-kernel@vger.kernel.org Cc: keescook@chromium.org, anton@enomsg.org, ccross@android.com, tony.luck@intel.com, Huang Yiwei , Mukesh Ojha Subject: [RESEND PATCH v2 2/2] pstore: Add buffer start check during init Date: Thu, 25 Feb 2021 21:30:17 +0530 Message-Id: <1614268817-7596-2-git-send-email-mojha@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1614268817-7596-1-git-send-email-mojha@codeaurora.org> References: <1614268817-7596-1-git-send-email-mojha@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Yiwei In a scenario of panic, when we use DRAM to store log instead of persistant storage and during warm reset when we copy these data outside of ram. Missing check on prz->start(write position) can cause crash because it can be any value and can point outside the mapped region. So add the start check to avoid. Signed-off-by: Huang Yiwei Signed-off-by: Mukesh Ojha --- change in v2: - this is on top of first patchset. fs/pstore/ram_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 0da012f..a15748a 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -514,7 +514,7 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, sig ^= PERSISTENT_RAM_SIG; if (prz->buffer->sig == sig) { - if (buffer_size(prz) == 0) { + if (buffer_size(prz) == 0 && buffer_start(prz) == 0) { pr_debug("found existing empty buffer\n"); return 0; } -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project