From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by dpdk.org (Postfix) with ESMTP id BA961CF9E for ; Tue, 17 Apr 2018 17:48:21 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Apr 2018 08:48:20 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,464,1517904000"; d="scan'208";a="32646976" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by fmsmga007.fm.intel.com with ESMTP; 17 Apr 2018 08:48:19 -0700 Received: from sivswdev01.ir.intel.com (sivswdev01.ir.intel.com [10.237.217.45]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id w3HFmIWC031006; Tue, 17 Apr 2018 16:48:18 +0100 Received: from sivswdev01.ir.intel.com (localhost [127.0.0.1]) by sivswdev01.ir.intel.com with ESMTP id w3HFmIJu024793; Tue, 17 Apr 2018 16:48:18 +0100 Received: (from aburakov@localhost) by sivswdev01.ir.intel.com with LOCAL id w3HFmIbf024789; Tue, 17 Apr 2018 16:48:18 +0100 From: Anatoly Burakov To: dev@dpdk.org Cc: thomas@monjalon.net, anatoly.burakov@intel.com Date: Tue, 17 Apr 2018 16:48:16 +0100 Message-Id: X-Mailer: git-send-email 1.7.0.7 In-Reply-To: References: In-Reply-To: References: Subject: [dpdk-dev] [PATCH 4/5] malloc: fix potential dereferencing of NULL pointer X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Apr 2018 15:48:22 -0000 Previous code checked for both first/last elements being NULL, but if they weren't, the expectation was that they're both non-NULL, which will be the case under normal conditions, but may not be the case due to heap structure corruption. Coverity issue: 272566 Fixes: bb372060dad4 ("malloc: make heap a doubly-linked list") Cc: anatoly.burakov@intel.com Signed-off-by: Anatoly Burakov --- lib/librte_eal/common/malloc_elem.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/lib/librte_eal/common/malloc_elem.c b/lib/librte_eal/common/malloc_elem.c index ee79dcd..af81961 100644 --- a/lib/librte_eal/common/malloc_elem.c +++ b/lib/librte_eal/common/malloc_elem.c @@ -49,6 +49,12 @@ malloc_elem_insert(struct malloc_elem *elem) struct malloc_elem *prev_elem, *next_elem; struct malloc_heap *heap = elem->heap; + /* first and last elements must be both NULL or both non-NULL */ + if ((heap->first == NULL) != (heap->last == NULL)) { + RTE_LOG(ERR, EAL, "Heap is probably corrupt\n"); + return; + } + if (heap->first == NULL && heap->last == NULL) { /* if empty heap */ heap->first = elem; -- 2.7.4