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=-14.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 5C363C433B4 for ; Mon, 17 May 2021 18:34:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A2D961001 for ; Mon, 17 May 2021 18:34:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237141AbhEQSfs (ORCPT ); Mon, 17 May 2021 14:35:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237050AbhEQSfs (ORCPT ); Mon, 17 May 2021 14:35:48 -0400 Received: from mail-lj1-x235.google.com (mail-lj1-x235.google.com [IPv6:2a00:1450:4864:20::235]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39707C061573; Mon, 17 May 2021 11:34:31 -0700 (PDT) Received: by mail-lj1-x235.google.com with SMTP id v6so8455940ljj.5; Mon, 17 May 2021 11:34:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=gPQVB2Gxpm829WebDVfYWATfDREweKl2ZF11NUCj36U=; b=r5irQvcboz80jzWteaD0Tgi6/vM06PZ17sWzl0p338iOE+oDhn4I1BHjKBDZRnpkyP e+FJ9NwG0wznJs5obORewSZFRZfDek/2hIgziLEeudXBqN+gGWsdjb5geKww0SBM1J1j wmFsTHtZIicLrXktt8dfFpovNICXUuvX5zlCBVo3Wr4NBKiqxfV6RKwZ2M0h4U3MT9Qd ljTIgwx0gdwJc6/u2FaALwRCaURkZy3vHoE+rBqurjjaD/azZsJPrrXgqF2PZ37myGEY 8VEo+Heg1EDMSvGPbRuhSBkSk4pr+IV3uUaYJ89eLsBf86kf2PFrHqJAy8yERHpyPZlC frSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=gPQVB2Gxpm829WebDVfYWATfDREweKl2ZF11NUCj36U=; b=EvBrDNPbNoTSj1qVIA759j/Xags0RI3vdfgO2bg4P4Xd5qK0v1mqfaeA1rXLzdYWFw KcVAxddLQusYmHODyOn76RRgYCCzuJCUO7EmjmHweSo+pj7KblQp5GRhq7IiyILMvkWK S8d81g8yubSiTZDkdfBx3xd+1eyHRFlYtFjkeH0KtEfzACHzSwqC7OpbonB0ttyaKMKV G08vVqIQgJ0ujTeLP7z3BDOmdQzzS8Ep230gtQkZ5d9tJIcwhbaXJn0ZIQ2td1aoThiu lJUeDn81Qdbs1R9cRjgFTktMOZfJgnj213Z1mv+j71anDaMNpAoMlzJ4Zw+aL4vuUBtO 93yQ== X-Gm-Message-State: AOAM530g5X13z6RsaIRYpRHZSC+ea4z76gOqYEUo0q7qLlCBriGZ/+uG 1V5j0djSeWVab+HV/a/vOt0= X-Google-Smtp-Source: ABdhPJwd3HpNJ6zf+bUM6K7ZqfzWMSfWRqib8AAwTPQ10ZqTPO9prVv3x2gDbl1KUXvn8KRInXCgTQ== X-Received: by 2002:a2e:22c4:: with SMTP id i187mr575687lji.465.1621276469689; Mon, 17 May 2021 11:34:29 -0700 (PDT) Received: from localhost.localdomain ([94.103.227.227]) by smtp.gmail.com with ESMTPSA id d16sm2040623lfm.202.2021.05.17.11.34.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 May 2021 11:34:29 -0700 (PDT) Date: Mon, 17 May 2021 21:34:27 +0300 From: Pavel Skripkin To: tytso@mit.edu, adilger.kernel@dilger.ca Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+d9e482e303930fa4f6ff@syzkaller.appspotmail.com Subject: Re: [PATCH v2] ext4: fix memory leak in ext4_fill_super Message-ID: <20210517213427.3ac17247@gmail.com> In-Reply-To: <20210517164034.1e7d712b@gmail.com> References: <20210430185046.15742-1-paskripkin@gmail.com> <20210517164034.1e7d712b@gmail.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Mon, 17 May 2021 16:40:34 +0300 Pavel Skripkin wrote: > Hi! > > Is all ok with this one, or I should send v3? :) > BTW, this patch fixes this bug as well https://syzkaller.appspot.com/bug?id=e2765a883959fd094e6a1c40f3502114fa17c550 With regards, Pavel Skripkin > With regards, > Pavel Skripkin > > On Fri, 30 Apr 2021 21:50:46 +0300 > Pavel Skripkin wrote: > > static int kthread(void *_create) will return -ENOMEM > > or -EINTR in case of internal failure or > > kthread_stop() call happens before threadfn call. > > > > To prevent fancy error checking and make code > > more straightforward we moved all cleanup code out > > of kmmpd threadfn. > > > > Also, dropped struct mmpd_data at all. Now struct super_block > > is a threadfn data and struct buffer_head embedded into > > struct ext4_sb_info. > > > > Reported-by: syzbot+d9e482e303930fa4f6ff@syzkaller.appspotmail.com > > Signed-off-by: Pavel Skripkin > > --- > > fs/ext4/ext4.h | 4 ++++ > > fs/ext4/mmp.c | 28 +++++++++++++--------------- > > fs/ext4/super.c | 10 ++++------ > > 3 files changed, 21 insertions(+), 21 deletions(-) > > > > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > > index 826a56e3bbd2..62210cbea84b 100644 > > --- a/fs/ext4/ext4.h > > +++ b/fs/ext4/ext4.h > > @@ -1490,6 +1490,7 @@ struct ext4_sb_info { > > struct kobject s_kobj; > > struct completion s_kobj_unregister; > > struct super_block *s_sb; > > + struct buffer_head *s_mmp_bh; > > > > /* Journaling */ > > struct journal_s *s_journal; > > @@ -3663,6 +3664,9 @@ extern struct ext4_io_end_vec > > *ext4_last_io_end_vec(ext4_io_end_t *io_end); /* mmp.c */ > > extern int ext4_multi_mount_protect(struct super_block *, > > ext4_fsblk_t); > > +/* mmp.c */ > > +extern void ext4_stop_mmpd(struct ext4_sb_info *sbi); > > + > > /* verity.c */ > > extern const struct fsverity_operations ext4_verityops; > > > > diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c > > index 795c3ff2907c..623bad399612 100644 > > --- a/fs/ext4/mmp.c > > +++ b/fs/ext4/mmp.c > > @@ -127,9 +127,9 @@ void __dump_mmp_msg(struct super_block *sb, > > struct mmp_struct *mmp, */ > > static int kmmpd(void *data) > > { > > - struct super_block *sb = ((struct mmpd_data *) data)->sb; > > - struct buffer_head *bh = ((struct mmpd_data *) data)->bh; > > + struct super_block *sb = (struct super_block *) data; > > struct ext4_super_block *es = EXT4_SB(sb)->s_es; > > + struct buffer_head *bh = EXT4_SB(sb)->s_mmp_bh; > > struct mmp_struct *mmp; > > ext4_fsblk_t mmp_block; > > u32 seq = 0; > > @@ -245,12 +245,18 @@ static int kmmpd(void *data) > > retval = write_mmp_block(sb, bh); > > > > exit_thread: > > - EXT4_SB(sb)->s_mmp_tsk = NULL; > > - kfree(data); > > - brelse(bh); > > return retval; > > } > > > > +void ext4_stop_mmpd(struct ext4_sb_info *sbi) > > +{ > > + if (sbi->s_mmp_tsk) { > > + kthread_stop(sbi->s_mmp_tsk); > > + brelse(sbi->s_mmp_bh); > > + sbi->s_mmp_tsk = NULL; > > + } > > +} > > + > > /* > > * Get a random new sequence number but make sure it is not greater > > than > > * EXT4_MMP_SEQ_MAX. > > @@ -275,7 +281,6 @@ int ext4_multi_mount_protect(struct super_block > > *sb, struct ext4_super_block *es = EXT4_SB(sb)->s_es; > > struct buffer_head *bh = NULL; > > struct mmp_struct *mmp = NULL; > > - struct mmpd_data *mmpd_data; > > u32 seq; > > unsigned int mmp_check_interval = > > le16_to_cpu(es->s_mmp_update_interval); unsigned int wait_time = 0; > > @@ -364,24 +369,17 @@ int ext4_multi_mount_protect(struct > > super_block *sb, goto failed; > > } > > > > - mmpd_data = kmalloc(sizeof(*mmpd_data), GFP_KERNEL); > > - if (!mmpd_data) { > > - ext4_warning(sb, "not enough memory for > > mmpd_data"); > > - goto failed; > > - } > > - mmpd_data->sb = sb; > > - mmpd_data->bh = bh; > > + EXT4_SB(sb)->s_mmp_bh = bh; > > > > /* > > * Start a kernel thread to update the MMP block > > periodically. */ > > - EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, mmpd_data, > > "kmmpd-%.*s", > > + EXT4_SB(sb)->s_mmp_tsk = kthread_run(kmmpd, sb, > > "kmmpd-%.*s", (int)sizeof(mmp->mmp_bdevname), > > bdevname(bh->b_bdev, > > mmp->mmp_bdevname)); > > if (IS_ERR(EXT4_SB(sb)->s_mmp_tsk)) { > > EXT4_SB(sb)->s_mmp_tsk = NULL; > > - kfree(mmpd_data); > > ext4_warning(sb, "Unable to create kmmpd thread for > > %s.", sb->s_id); > > goto failed; > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > > index b9693680463a..539f89c5431f 100644 > > --- a/fs/ext4/super.c > > +++ b/fs/ext4/super.c > > @@ -1244,8 +1244,8 @@ static void ext4_put_super(struct super_block > > *sb) ext4_xattr_destroy_cache(sbi->s_ea_block_cache); > > sbi->s_ea_block_cache = NULL; > > > > - if (sbi->s_mmp_tsk) > > - kthread_stop(sbi->s_mmp_tsk); > > + ext4_stop_mmpd(sbi); > > + > > brelse(sbi->s_sbh); > > sb->s_fs_info = NULL; > > /* > > @@ -5156,8 +5156,7 @@ static int ext4_fill_super(struct super_block > > *sb, void *data, int silent) failed_mount3: > > flush_work(&sbi->s_error_work); > > del_timer_sync(&sbi->s_err_report); > > - if (sbi->s_mmp_tsk) > > - kthread_stop(sbi->s_mmp_tsk); > > + ext4_stop_mmpd(sbi); > > failed_mount2: > > rcu_read_lock(); > > group_desc = rcu_dereference(sbi->s_group_desc); > > @@ -5952,8 +5951,7 @@ static int ext4_remount(struct super_block > > *sb, int *flags, char *data) */ > > ext4_mark_recovery_complete(sb, > > es); } > > - if (sbi->s_mmp_tsk) > > - kthread_stop(sbi->s_mmp_tsk); > > + ext4_stop_mmpd(sbi); > > } else { > > /* Make sure we can mount this feature set > > readwrite */ if (ext4_has_feature_readonly(sb) || >