From patchwork Thu Apr 28 03:42:20 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?Q2h1bmZlbmcgWXVuICjkupHmmKXls7Ap?= X-Patchwork-Id: 8965351 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8915CBF29F for ; Thu, 28 Apr 2016 03:44:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C0D842027D for ; Thu, 28 Apr 2016 03:44:41 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 02B032022A for ; Thu, 28 Apr 2016 03:44:41 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1avcr7-0002by-IR; Thu, 28 Apr 2016 03:43:09 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1avcqy-0002YK-88; Thu, 28 Apr 2016 03:43:00 +0000 Received: from mtkhts09.mediatek.inc [(172.21.101.70)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1650830352; Thu, 28 Apr 2016 11:42:35 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkhts09.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.266.1; Thu, 28 Apr 2016 11:42:33 +0800 From: Chunfeng Yun To: Greg Kroah-Hartman Subject: [PATCH v2 1/2] usb: core: buffer: avoid NULL pointer dereferrence Date: Thu, 28 Apr 2016 11:42:20 +0800 Message-ID: <1461814941-28345-1-git-send-email-chunfeng.yun@mediatek.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160427_204300_481733_D541807B X-CRM114-Status: UNSURE ( 7.98 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -1.1 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Felipe Balbi , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, Chunfeng Yun , Alan Stern , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP NULL pointer dereferrence will happen when class driver wants to allocate zero length buffer and pool_max[0] can't be used, so simply returns NULL in the case. Signed-off-by: Chunfeng Yun --- drivers/usb/core/buffer.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c index 2741566..98e39f9 100644 --- a/drivers/usb/core/buffer.c +++ b/drivers/usb/core/buffer.c @@ -122,6 +122,9 @@ void *hcd_buffer_alloc( struct usb_hcd *hcd = bus_to_hcd(bus); int i; + if (size == 0) + return NULL; + /* some USB hosts just use PIO */ if (!IS_ENABLED(CONFIG_HAS_DMA) || (!bus->controller->dma_mask &&