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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 B5FBAC33CA3 for ; Fri, 10 Jan 2020 22:07:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F0A820678 for ; Fri, 10 Jan 2020 22:07:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578694079; bh=V3GbiHcfk6BfHbV+lS0V0Esc5dLq3FYLB6Xqf/5iltk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YlE1zLg4riTN5o78QVOr/rqVgCyfG8byRPx6ntFd6oyoDlrHvHjNhSjIb0CsC2PqZ Y0gcYWcTfD4ri/dbZuu9U6m+XRI/X28ZNSYo1/NInTasceHz71W4dIiNwAU7Sivpgc BOiImOzeesH3rFUL8XIxq9JRo6r/Huk6IKd+wWfI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728366AbgAJWHa (ORCPT ); Fri, 10 Jan 2020 17:07:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:55190 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728063AbgAJWH0 (ORCPT ); Fri, 10 Jan 2020 17:07:26 -0500 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 B756F21569; Fri, 10 Jan 2020 22:07:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578694045; bh=V3GbiHcfk6BfHbV+lS0V0Esc5dLq3FYLB6Xqf/5iltk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=10aczAVCN5InKBNkPy8RNtszHE/ArUo6nnwejsmxE3Rs9sIxqJay/AH+TZp+EyboE XXjgDc/82A19wJGCbSzGnNBqXYKBIvtAd0M2mF0CZmkHC0lxCkHCrCi/gQuaql8jVB lezaN31s24oB8pzbmISkMMzXfm5YRX9J3f0k8Utg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Alexander.Barabash@dell.com" , Alexander Barabash , Dave Jiang , Vinod Koul , Sasha Levin , dmaengine@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 3/6] ioat: ioat_alloc_ring() failure handling. Date: Fri, 10 Jan 2020 17:07:18 -0500 Message-Id: <20200110220721.28780-3-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200110220721.28780-1-sashal@kernel.org> References: <20200110220721.28780-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Alexander.Barabash@dell.com" [ Upstream commit b0b5ce1010ffc50015eaec72b0028aaae3f526bb ] If dma_alloc_coherent() returns NULL in ioat_alloc_ring(), ring allocation must not proceed. Until now, if the first call to dma_alloc_coherent() in ioat_alloc_ring() returned NULL, the processing could proceed, failing with NULL-pointer dereferencing further down the line. Signed-off-by: Alexander Barabash Acked-by: Dave Jiang Link: https://lore.kernel.org/r/75e9c0e84c3345d693c606c64f8b9ab5@x13pwhopdag1307.AMER.DELL.COM Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/ioat/dma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c index 49386ce04bf5..1389f0582e29 100644 --- a/drivers/dma/ioat/dma.c +++ b/drivers/dma/ioat/dma.c @@ -394,10 +394,11 @@ ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags) descs->virt = dma_alloc_coherent(to_dev(ioat_chan), SZ_2M, &descs->hw, flags); - if (!descs->virt && (i > 0)) { + if (!descs->virt) { int idx; for (idx = 0; idx < i; idx++) { + descs = &ioat_chan->descs[idx]; dma_free_coherent(to_dev(ioat_chan), SZ_2M, descs->virt, descs->hw); descs->virt = NULL; -- 2.20.1