From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22D10C54E49 for ; Thu, 7 May 2020 14:27:48 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DA9E42083B for ; Thu, 7 May 2020 14:27:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="DMHWu1yN"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="e0s4o+5E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DA9E42083B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=RbTOa1nnAzgJtnJjvrSFjHgaLen1QiiOmFFK9N77VoM=; b=DMHWu1yNoIOJMQ wM6RmUHjKOhZ0q4jkPnE9sI3WIo8kMHnSg8EXXq1PsVaCNzPad5swcXAKRfLHZb0XUfhjJ2n7e018 sDBXtN8QmX9Fdy1eNwUIrMM0l88pQ7NGBpYLKK68ktrFfU+8bS1UUYaYSD4rZR/lyZ+lrdxhCDGIA TTqawAD+gb9ASqmEVpA+gsXb4lEbx4cRdx4DdyLaLMo/N3jyrU2YOlZWgPEnGgOODYFPtJexLsAIH UFlgZ3XvMKZMA9Xi7wlOUc5Bej+uCbqX1Nqq1eMiOlwCqdYiciiCGnWj26hwBRQNgu4QlXir8Xs6l gpOEKket6i77dPQ2jK1Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWhV3-0001F2-Un; Thu, 07 May 2020 14:27:45 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jWhUs-00012O-1L for linux-arm-kernel@lists.infradead.org; Thu, 07 May 2020 14:27:39 +0000 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 798162083B; Thu, 7 May 2020 14:27:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588861653; bh=nldiJ+MHYYN+kjgAX5mo6jUIk7pC/Xc/j4g2G7Uco6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=e0s4o+5EI+KKTv1EgVraZSnAfNcypP9onwpJf01GmePNVCzCRa9kHDOdp2JmKvYAR QtzvVzwnfVW3XUo6M556Gizb5EI8oMj9cvYjDBNL59gnAAmOwQK3XM/R7wVj+WZJUZ eA8cU4ZevAU/7OzP0/EfaWKkx4XzjRT8pJYN7l+g= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.6 05/50] dmaengine: xilinx_dma: Add missing check for empty list Date: Thu, 7 May 2020 10:26:41 -0400 Message-Id: <20200507142726.25751-5-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200507142726.25751-1-sashal@kernel.org> References: <20200507142726.25751-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200507_072734_112078_8425851C X-CRM114-Status: GOOD ( 11.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , Radhey Shyam Pandey , Vinod Koul , Sebastian von Ohr , dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Sebastian von Ohr [ Upstream commit b269426011bcfd97b7c3101abfe1a99147b6f40b ] The DMA transfer might finish just after checking the state with dma_cookie_status, but before the lock is acquired. Not checking for an empty list in xilinx_dma_tx_status may result in reading random data or data corruption when desc is written to. This can be reliably triggered by using dma_sync_wait to wait for DMA completion. Signed-off-by: Sebastian von Ohr Tested-by: Radhey Shyam Pandey Link: https://lore.kernel.org/r/20200303130518.333-1-vonohr@smaract.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/xilinx/xilinx_dma.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index a9c5d5cc9f2bd..5d5f1d0ce16cb 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -1229,16 +1229,16 @@ static enum dma_status xilinx_dma_tx_status(struct dma_chan *dchan, return ret; spin_lock_irqsave(&chan->lock, flags); - - desc = list_last_entry(&chan->active_list, - struct xilinx_dma_tx_descriptor, node); - /* - * VDMA and simple mode do not support residue reporting, so the - * residue field will always be 0. - */ - if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA) - residue = xilinx_dma_get_residue(chan, desc); - + if (!list_empty(&chan->active_list)) { + desc = list_last_entry(&chan->active_list, + struct xilinx_dma_tx_descriptor, node); + /* + * VDMA and simple mode do not support residue reporting, so the + * residue field will always be 0. + */ + if (chan->has_sg && chan->xdev->dma_config->dmatype != XDMA_TYPE_VDMA) + residue = xilinx_dma_get_residue(chan, desc); + } spin_unlock_irqrestore(&chan->lock, flags); dma_set_residue(txstate, residue); -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel