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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 8690DC433E3 for ; Tue, 16 Jun 2020 15:05:40 +0000 (UTC) Received: from krantz.zx2c4.com (krantz.zx2c4.com [192.95.5.69]) (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 39942208B8 for ; Tue, 16 Jun 2020 15:05:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HXehFBmm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 39942208B8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=wireguard-bounces@lists.zx2c4.com Received: by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 83413cd2; Tue, 16 Jun 2020 14:47:40 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id cb35a742 for ; Tue, 16 Jun 2020 14:47:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592319936; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rXbjvJPZU9GzTq8LOO4SZ69J1AJAOxGiWdFnkvpgDCI=; b=HXehFBmmXrJjPB68vZLiUa43vbIhWhl/xo31Y43zN+K7lI7kZ3VFPelGQqBvrx53NkSvyh tTAuQ/xDSObfzwhjkj9Q5TK5ehgxrG7yGSF/TX/vewwhnxWtdOiwIJBgEAw6VNtIxWxnK3 APBRtIwZWyOT5cpFEzcUZkWaZVpxR9k= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-347-rhm5WjahMFKJc8Xm5_1I2g-1; Tue, 16 Jun 2020 11:05:32 -0400 X-MC-Unique: rhm5WjahMFKJc8Xm5_1I2g-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6B20C100CCC9; Tue, 16 Jun 2020 15:05:27 +0000 (UTC) Received: from llong.remote.csb (ovpn-114-156.rdu2.redhat.com [10.10.114.156]) by smtp.corp.redhat.com (Postfix) with ESMTP id 897CF7890A; Tue, 16 Jun 2020 15:05:22 +0000 (UTC) Subject: Re: [PATCH v4 3/3] btrfs: Use kfree() in btrfs_ioctl_get_subvol_info() To: dsterba@suse.cz, Andrew Morton , David Howells , Jarkko Sakkinen , James Morris , "Serge E. Hallyn" , Linus Torvalds , Joe Perches , Matthew Wilcox , David Rientjes , Michal Hocko , Johannes Weiner , Dan Carpenter , "Jason A . Donenfeld" , linux-mm@kvack.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-pm@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-amlogic@lists.infradead.org, linux-mediatek@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-ppp@vger.kernel.org, wireguard@lists.zx2c4.com, linux-wireless@vger.kernel.org, devel@driverdev.osuosl.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-fscrypt@vger.kernel.org, ecryptfs@vger.kernel.org, kasan-dev@googlegroups.com, linux-bluetooth@vger.kernel.org, linux-wpan@vger.kernel.org, linux-sctp@vger.kernel.org, linux-nfs@vger.kernel.org, tipc-discussion@lists.sourceforge.net, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org References: <20200616015718.7812-1-longman@redhat.com> <20200616015718.7812-4-longman@redhat.com> <20200616144804.GD27795@twin.jikos.cz> From: Waiman Long Organization: Red Hat Message-ID: <75152002-5f02-04b6-a811-29ef79961e0b@redhat.com> Date: Tue, 16 Jun 2020 11:05:22 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200616144804.GD27795@twin.jikos.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" On 6/16/20 10:48 AM, David Sterba wrote: > On Mon, Jun 15, 2020 at 09:57:18PM -0400, Waiman Long wrote: >> In btrfs_ioctl_get_subvol_info(), there is a classic case where kzalloc() >> was incorrectly paired with kzfree(). According to David Sterba, there >> isn't any sensitive information in the subvol_info that needs to be >> cleared before freeing. So kfree_sensitive() isn't really needed, >> use kfree() instead. >> >> Reported-by: David Sterba >> Signed-off-by: Waiman Long >> --- >> fs/btrfs/ioctl.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c >> index f1dd9e4271e9..e8f7c5f00894 100644 >> --- a/fs/btrfs/ioctl.c >> +++ b/fs/btrfs/ioctl.c >> @@ -2692,7 +2692,7 @@ static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) >> btrfs_put_root(root); >> out_free: >> btrfs_free_path(path); >> - kfree_sensitive(subvol_info); >> + kfree(subvol_info); > I would rather merge a patch doing to kzfree -> kfree instead of doing > the middle step to switch it to kfree_sensitive. If it would help > integration of your patchset I can push it to the next rc so there are > no kzfree left in the btrfs code. Treewide change like that can take > time so it would be one less problem to care about for you. > Sure, I will move it forward in the patch series. Thanks, Longman