From patchwork Thu Sep 29 18:14:38 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 9356903 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C52A56077A for ; Thu, 29 Sep 2016 18:16:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BA2F7298E7 for ; Thu, 29 Sep 2016 18:16:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AE89F29B96; Thu, 29 Sep 2016 18:16:51 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id 9A2F9298E7 for ; Thu, 29 Sep 2016 18:16:50 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bpfrO-0000vt-BU; Thu, 29 Sep 2016 18:15:06 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bpfrK-0000fz-Vx for linux-arm-kernel@lists.infradead.org; Thu, 29 Sep 2016 18:15:04 +0000 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1bpfqw-0004rJ-So; Thu, 29 Sep 2016 18:14:38 +0000 From: Colin King To: Linus Walleij , Dan Williams , Vinod Koul , linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org Subject: [PATCH][V2] dmaengine: coh901318: fix integer overflow when shifting more than 32 places Date: Thu, 29 Sep 2016 19:14:38 +0100 Message-Id: <20160929181438.14374-1-colin.king@canonical.com> X-Mailer: git-send-email 2.9.3 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160929_111503_250298_CAB6992B X-CRM114-Status: GOOD ( 10.64 ) 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: linux-kernel@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Colin Ian King Currently U300_DMA_CHANNELS is set to 40, meaning that the shift of 1 can be more than 32 places, which leads to a 32 bit integer overflow. Fix this by using 1ULL instead of 1 before shifting it. Also add braces on the for-loop to keep with coding style conventions. Signed-off-by: Colin Ian King --- drivers/dma/coh901318.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c index 2835f3e..74794c9 100644 --- a/drivers/dma/coh901318.c +++ b/drivers/dma/coh901318.c @@ -1352,9 +1352,10 @@ static ssize_t coh901318_debugfs_read(struct file *file, char __user *buf, tmp += sprintf(tmp, "DMA -- enabled dma channels\n"); - for (i = 0; i < U300_DMA_CHANNELS; i++) - if (started_channels & (1 << i)) + for (i = 0; i < U300_DMA_CHANNELS; i++) { + if (started_channels & (1ULL << i)) tmp += sprintf(tmp, "channel %d\n", i); + } tmp += sprintf(tmp, "Pool alloc nbr %d\n", pool_count);