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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BDC0C433FE for ; Mon, 7 Nov 2022 10:23:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231423AbiKGKXC (ORCPT ); Mon, 7 Nov 2022 05:23:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231243AbiKGKWm (ORCPT ); Mon, 7 Nov 2022 05:22:42 -0500 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A01D4183BD; Mon, 7 Nov 2022 02:22:41 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 53678225CC; Mon, 7 Nov 2022 10:22:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1667816560; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jCn4MseqJcnTtCYiGPVCPesbMSniSjoMzrXJhKB4vOo=; b=XaQBv0h9JvOYe7ohJxNKojp4Gtl5Alz8BCNE73/RUsBKadqlIIfNqd7q4NI0AFPJ/SDHDs mEKdVd97gJJo2+CmnHBqB9rq/ePUz3+wytLxKPYfcWdtSLCVMvYV6FdGmJJtDYrp4GYdYF jMWdzsuBq9Zz30AOd1MfRbQGuukHvmk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1667816560; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jCn4MseqJcnTtCYiGPVCPesbMSniSjoMzrXJhKB4vOo=; b=g7JjvHSdfn1Wj9M/78AHzwkucfxbJUA4DRoLNUT68gTUjyaBkgq+AKVKY8vbi7Wv6/9aDf ZBlnYrFLauvWwmCg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id EE47C13AC7; Mon, 7 Nov 2022 10:22:39 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id yXU8N2/caGMibQAAMHmgww (envelope-from ); Mon, 07 Nov 2022 10:22:39 +0000 Received: from localhost (brahms.olymp [local]) by brahms.olymp (OpenSMTPD) with ESMTPA id 6389e19a; Mon, 7 Nov 2022 10:23:41 +0000 (UTC) Date: Mon, 7 Nov 2022 10:23:41 +0000 From: =?iso-8859-1?Q?Lu=EDs?= Henriques To: Xiubo Li Cc: Ilya Dryomov , Jeff Layton , ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ceph: fix memory leak in mount error path when using test_dummy_encryption Message-ID: References: <20221103153619.11068-1-lhenriques@suse.de> <700018a6-aff7-6e7a-98df-2fc8cca39acb@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <700018a6-aff7-6e7a-98df-2fc8cca39acb@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 07, 2022 at 03:47:23PM +0800, Xiubo Li wrote: > > On 03/11/2022 23:36, Luís Henriques wrote: > > Because ceph_init_fs_context() will never be invoced in case we get a > > mount error, destroy_mount_options() won't be releasing fscrypt resources > > with fscrypt_free_dummy_policy(). This will result in a memory leak. Add > > an invocation to this function in the mount error path. > > > > Signed-off-by: Luís Henriques > > --- > > fs/ceph/super.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/fs/ceph/super.c b/fs/ceph/super.c > > index 2224d44d21c0..6b9fd04b25cd 100644 > > --- a/fs/ceph/super.c > > +++ b/fs/ceph/super.c > > @@ -1362,6 +1362,7 @@ static int ceph_get_tree(struct fs_context *fc) > > ceph_mdsc_close_sessions(fsc->mdsc); > > deactivate_locked_super(sb); > > + fscrypt_free_dummy_policy(&fsc->fsc_dummy_enc_policy); > > Hi Luis, > > BTW, any reason the following code won't be triggered ? > > deactivate_locked_super(sb); > >   --> fs->kill_sb(s); > >         --> ceph_kill_sb() > >               --> kill_anon_super() > >                     --> generic_shutdown_super() > >                           --> sop->put_super() > >                                 --> ceph_put_super() > >                                       --> ceph_fscrypt_free_dummy_policy() > >                                            --> fscrypt_free_dummy_policy( > Here's what I'm seeing here: sys_mount->path_mount->do_new_mount->vfs_get_tree->ceph_get_tree ceph_get_tree() fails due to ceph_real_mount() returning an error. My understanding is that that, since fc->root is never set, that code path will never be triggered. Does that make sense? An easy way to reproduce is by running fstest ceph/005 with the 'test_dummy_encryption' option. (I'll probably need to send a patch to disable this test when this option is present.) Cheers, -- Luís