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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 3AA2FCA90AF for ; Tue, 12 May 2020 17:07:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16BA2206B8 for ; Tue, 12 May 2020 17:07:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727096AbgELRH1 (ORCPT ); Tue, 12 May 2020 13:07:27 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43412 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725938AbgELRH1 (ORCPT ); Tue, 12 May 2020 13:07:27 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jYYND-0001Xv-Me; Tue, 12 May 2020 17:07:19 +0000 From: Colin King To: Kees Cook , Anton Vorontsov , Colin Cross , Tony Luck , WeiXiong Liao Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH][next] pstore/zone,blk: fix dereference of pointer before it has been null checked Date: Tue, 12 May 2020 18:07:19 +0100 Message-Id: <20200512170719.221514-1-colin.king@canonical.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Colin Ian King Currently the assignment of ctx dereferences pointer 'record' before the pointer has been null checked. Fix this by only making this dereference after it has been null checked close to the point ctx is to be used. Addresses-Coverity: ("Dereference before null check") Fixes: bb4ccd1e6f56 ("pstore/zone,blk: Add ftrace frontend support") Signed-off-by: Colin Ian King --- fs/pstore/zone.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/pstore/zone.c b/fs/pstore/zone.c index bd8e194110fc..c5bf3b9f644f 100644 --- a/fs/pstore/zone.c +++ b/fs/pstore/zone.c @@ -998,7 +998,7 @@ static ssize_t psz_kmsg_read(struct pstore_zone *zone, static ssize_t psz_ftrace_read(struct pstore_zone *zone, struct pstore_record *record) { - struct psz_context *cxt = record->psi->data; + struct psz_context *cxt; struct psz_buffer *buf; int ret; @@ -1018,6 +1018,7 @@ static ssize_t psz_ftrace_read(struct pstore_zone *zone, return ret; out: + cxt = record->psi->data; if (cxt->ftrace_read_cnt < cxt->ftrace_max_cnt) /* then, read next ftrace zone */ return -ENOMSG; -- 2.25.1