From patchwork Thu Nov 28 17:44:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Ivanov X-Patchwork-Id: 1202248 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=cambridgegreys.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="pXboqNQb"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 47P4lP4nWLz9sP3 for ; Fri, 29 Nov 2019 04:44:33 +1100 (AEDT) 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: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:In-Reply-To:References: List-Owner; bh=EuhEv1x50djiGr/uXyvct3EQ4qMcZ8poo/JAWSrkSbE=; b=pXboqNQb8NVamK L7k3inTHYqnZnQ+K5ckiI7/J+/4MIk4EBIpd9+NBmcLMzEjIqw8l2csCCwr6H10/vskJgc0deSxhm WE7QMuu533rp1/jUrCQv9m1ikrzuKlx6rrNkYWnMbcYsVD4+aEGVZbnH2hos+3sGEtqO9Z7TJx6U8 vfoBNg7s1GajjvJ8vq8d5lWqlg0TA5gA7GgAo9ZVrIa00TbCCpSwJ+FY56XHEPU7L7BdzwtbSgesC wFUUYa4TVBDA3NHDe92CjJkvFkHPJ4UtQf4eRBouGa2X7ZKKMg20vjkrQKJmibGmjQg9mgybyahT9 vb9Yc7PtCbjcIOC1Cqvw==; 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 1iaNq6-0003YS-Jp; Thu, 28 Nov 2019 17:44:26 +0000 Received: from ivanoab7.miniserver.com ([37.128.132.42] helo=www.kot-begemot.co.uk) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iaNq4-0003Y6-DF for linux-um@lists.infradead.org; Thu, 28 Nov 2019 17:44:25 +0000 Received: from tun252.jain.kot-begemot.co.uk ([192.168.18.6] helo=jain.kot-begemot.co.uk) by www.kot-begemot.co.uk with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1iaNq0-0007Yx-TF; Thu, 28 Nov 2019 17:44:21 +0000 Received: from jain.kot-begemot.co.uk ([192.168.3.3]) by jain.kot-begemot.co.uk with esmtp (Exim 4.92) (envelope-from ) id 1iaNpx-000189-2a; Thu, 28 Nov 2019 17:44:18 +0000 From: anton.ivanov@cambridgegreys.com To: linux-um@lists.infradead.org Subject: [PATCH] um: vector: fix BPF loading in vector drivers Date: Thu, 28 Nov 2019 17:44:05 +0000 Message-Id: <20191128174405.4244-1-anton.ivanov@cambridgegreys.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Spam-Score: -1.0 X-Spam-Score: -1.0 X-Clacks-Overhead: GNU Terry Pratchett X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191128_094424_443921_63BCB150 X-CRM114-Status: GOOD ( 10.63 ) X-Spam-Score: 0.4 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (0.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_NONE SPF: sender does not publish an SPF Record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.4 KHOP_HELO_FCRDNS Relay HELO differs from its IP's reverse DNS X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: songliubraving@fb.com, daniel@iogearbox.net, richard@nod.at, kernel-janitors@vger.kernel.org, ast@kernel.org, weiyongjun1@huawei.com, netdev@vger.kernel.org, bpf@vger.kernel.org, kafai@fb.com, dan.carpenter@oracle.com, Anton Ivanov Sender: "linux-um" Errors-To: linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org From: Anton Ivanov This fixes a possible hang in bpf firmware loading in the UML vector io drivers due to use of GFP_KERNEL while holding a spinlock. Based on a prposed fix by weiyongjun1@huawei.com and suggestions for improving it by dan.carpenter@oracle.com Signed-off-by: Anton Ivanov --- arch/um/drivers/vector_kern.c | 38 ++++++++++++++++++----------------- 1 file changed, 20 insertions(+), 18 deletions(-) diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c index 92617e16829e..dbbc6e850fdd 100644 --- a/arch/um/drivers/vector_kern.c +++ b/arch/um/drivers/vector_kern.c @@ -1387,6 +1387,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev, struct vector_private *vp = netdev_priv(dev); struct vector_device *vdevice; const struct firmware *fw; + void *new_filter; int result = 0; if (!(vp->options & VECTOR_BPF_FLASH)) { @@ -1394,6 +1395,15 @@ static int vector_net_load_bpf_flash(struct net_device *dev, return -1; } + vdevice = find_device(vp->unit); + + if (request_firmware(&fw, efl->data, &vdevice->pdev.dev)) + return -1; + + new_filter = kmemdup(fw->data, fw->size, GFP_KERNEL); + if (!new_filter) + goto free_buffer; + spin_lock(&vp->lock); if (vp->bpf != NULL) { @@ -1402,41 +1412,33 @@ static int vector_net_load_bpf_flash(struct net_device *dev, kfree(vp->bpf->filter); vp->bpf->filter = NULL; } else { - vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_KERNEL); + vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_ATOMIC); if (vp->bpf == NULL) { netdev_err(dev, "failed to allocate memory for firmware\n"); - goto flash_fail; + goto apply_flash_fail; } } - vdevice = find_device(vp->unit); - - if (request_firmware(&fw, efl->data, &vdevice->pdev.dev)) - goto flash_fail; - - vp->bpf->filter = kmemdup(fw->data, fw->size, GFP_KERNEL); - if (!vp->bpf->filter) - goto free_buffer; - + vp->bpf->filter = new_filter; vp->bpf->len = fw->size / sizeof(struct sock_filter); - release_firmware(fw); if (vp->opened) result = uml_vector_attach_bpf(vp->fds->rx_fd, vp->bpf); spin_unlock(&vp->lock); - return result; - -free_buffer: release_firmware(fw); -flash_fail: + return result; + +apply_flash_fail: spin_unlock(&vp->lock); - if (vp->bpf != NULL) + if (vp->bpf) kfree(vp->bpf->filter); kfree(vp->bpf); - vp->bpf = NULL; + +free_buffer: + release_firmware(fw); return -1; }