From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751919AbdIMSlY (ORCPT ); Wed, 13 Sep 2017 14:41:24 -0400 Received: from mout02.posteo.de ([185.67.36.66]:50105 "EHLO mout02.posteo.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751148AbdIMSlV (ORCPT ); Wed, 13 Sep 2017 14:41:21 -0400 From: Martin Kepplinger To: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com Cc: devel@linuxdriverproject.org, linux-kernel@vger.kernel.org, Martin Kepplinger Subject: [PATCH] tools: hv: hv_kvp_daemon: fix usage of realloc() Date: Wed, 13 Sep 2017 20:41:02 +0200 Message-Id: <20170913184102.25330-1-martink@posteo.de> X-Mailer: git-send-email 2.11.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org realloc() returns NULL in case it fails. Since we don't save the pointer in question elsewhere, we leak memory by assigning NULL to the original memory in the heap. realloc() doesn't free memory in case of failure, so let's do it manually. Signed-off-by: Martin Kepplinger --- tools/hv/hv_kvp_daemon.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c index eaa3bec273c8..0b3b18d0a6e3 100644 --- a/tools/hv/hv_kvp_daemon.c +++ b/tools/hv/hv_kvp_daemon.c @@ -231,6 +231,7 @@ static int kvp_file_init(void) size_t records_read; char *fname; struct kvp_record *record; + struct kvp_record *record_tmp; struct kvp_record *readp; int num_blocks; int i; @@ -284,12 +285,15 @@ static int kvp_file_init(void) * We have more data to read. */ num_blocks++; - record = realloc(record, alloc_unit * + record_tmp = realloc(record, alloc_unit * num_blocks); - if (record == NULL) { + if (!record_tmp) { + free(record); fclose(filep); close(fd); return 1; + } else { + record = record_tmp; } continue; } @@ -355,6 +359,7 @@ static int kvp_key_add_or_modify(int pool, const __u8 *key, int key_size, int i; int num_records; struct kvp_record *record; + struct kvp_record *record_tmp; int num_blocks; if ((key_size > HV_KVP_EXCHANGE_MAX_KEY_SIZE) || @@ -387,11 +392,15 @@ static int kvp_key_add_or_modify(int pool, const __u8 *key, int key_size, */ if (num_records == (ENTRIES_PER_BLOCK * num_blocks)) { /* Need to allocate a larger array for reg entries. */ - record = realloc(record, sizeof(struct kvp_record) * + record_tmp = realloc(record, sizeof(struct kvp_record) * ENTRIES_PER_BLOCK * (num_blocks + 1)); - if (record == NULL) + if (!record_tmp) { + free(record); return 1; + } else { + record = record_tmp; + } kvp_file_info[pool].num_blocks++; } -- 2.11.0