From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johannes Thumshirn , Johannes Berg , Kalle Valo , Amit Pundir Subject: [PATCH 3.18 75/83] cw1200: Dont leak memory if krealloc failes Date: Thu, 29 Nov 2018 15:12:33 +0100 Message-Id: <20181129140142.284783623@linuxfoundation.org> In-Reply-To: <20181129140138.002176596@linuxfoundation.org> References: <20181129140138.002176596@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Thumshirn commit 9afdd6128c39f42398041bb2e017d8df0dcebcd1 upstream. The call to krealloc() in wsm_buf_reserve() directly assigns the newly returned memory to buf->begin. This is all fine except when krealloc() failes we loose the ability to free the old memory pointed to by buf->begin. If we just create a temporary variable to assign memory to and assign the memory to it we can mitigate the memory leak. Signed-off-by: Johannes Thumshirn Cc: Johannes Berg Signed-off-by: Kalle Valo Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/cw1200/wsm.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) --- a/drivers/net/wireless/cw1200/wsm.c +++ b/drivers/net/wireless/cw1200/wsm.c @@ -1807,16 +1807,18 @@ static int wsm_buf_reserve(struct wsm_bu { size_t pos = buf->data - buf->begin; size_t size = pos + extra_size; + u8 *tmp; size = round_up(size, FWLOAD_BLOCK_SIZE); - buf->begin = krealloc(buf->begin, size, GFP_KERNEL | GFP_DMA); - if (buf->begin) { - buf->data = &buf->begin[pos]; - buf->end = &buf->begin[size]; - return 0; - } else { - buf->end = buf->data = buf->begin; + tmp = krealloc(buf->begin, size, GFP_KERNEL | GFP_DMA); + if (!tmp) { + wsm_buf_deinit(buf); return -ENOMEM; } + + buf->begin = tmp; + buf->data = &buf->begin[pos]; + buf->end = &buf->begin[size]; + return 0; }