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 14B85C433FE for ; Wed, 30 Nov 2022 18:48:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231367AbiK3Ssu (ORCPT ); Wed, 30 Nov 2022 13:48:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231370AbiK3Ssb (ORCPT ); Wed, 30 Nov 2022 13:48:31 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E236F55C89 for ; Wed, 30 Nov 2022 10:48:29 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 88B9CB81CA6 for ; Wed, 30 Nov 2022 18:48:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1A9AC433D7; Wed, 30 Nov 2022 18:48:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669834107; bh=e1+IPermuFw4Yw3pOuO4vGYU2ZVKupHQgopAVJll2vw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l1XQWC3sfxUNWnpd8K+mu5oPVpGlv6NxYs/TmEG7tki8CoZboAShGtC+//ca/ndCQ eMA+UiI2e0IwIWBDBuxCgcxkf4icmns4TCMh7Zuf5PMSBTfZEnWesFKDMwRgXKbhKP rjYkXaQIrKTtdkYNTWoDOk5IcCLvUNGVnG0GQ0VU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+6ba92bd00d5093f7e371@syzkaller.appspotmail.com, Jan Kara , Svyatoslav Feldsherov , Theodore Tso , Sasha Levin Subject: [PATCH 6.0 131/289] fs: do not update freeing inode i_io_list Date: Wed, 30 Nov 2022 19:21:56 +0100 Message-Id: <20221130180547.109020051@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221130180544.105550592@linuxfoundation.org> References: <20221130180544.105550592@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Svyatoslav Feldsherov [ Upstream commit 4e3c51f4e805291b057d12f5dda5aeb50a538dc4 ] After commit cbfecb927f42 ("fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODE") writeback_single_inode can push inode with I_DIRTY_TIME set to b_dirty_time list. In case of freeing inode with I_DIRTY_TIME set this can happen after deletion of inode from i_io_list at evict. Stack trace is following. evict fat_evict_inode fat_truncate_blocks fat_flush_inodes writeback_inode sync_inode_metadata(inode, sync=0) writeback_single_inode(inode, wbc) <- wbc->sync_mode == WB_SYNC_NONE This will lead to use after free in flusher thread. Similar issue can be triggered if writeback_single_inode in the stack trace update inode->i_io_list. Add explicit check to avoid it. Fixes: cbfecb927f42 ("fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODE") Reported-by: syzbot+6ba92bd00d5093f7e371@syzkaller.appspotmail.com Reviewed-by: Jan Kara Signed-off-by: Svyatoslav Feldsherov Link: https://lore.kernel.org/r/20221115202001.324188-1-feldsherov@google.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/fs-writeback.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 443f83382b9b..9958d4020771 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1712,18 +1712,26 @@ static int writeback_single_inode(struct inode *inode, wb = inode_to_wb_and_lock_list(inode); spin_lock(&inode->i_lock); /* - * If the inode is now fully clean, then it can be safely removed from - * its writeback list (if any). Otherwise the flusher threads are - * responsible for the writeback lists. + * If the inode is freeing, its i_io_list shoudn't be updated + * as it can be finally deleted at this moment. */ - if (!(inode->i_state & I_DIRTY_ALL)) - inode_cgwb_move_to_attached(inode, wb); - else if (!(inode->i_state & I_SYNC_QUEUED)) { - if ((inode->i_state & I_DIRTY)) - redirty_tail_locked(inode, wb); - else if (inode->i_state & I_DIRTY_TIME) { - inode->dirtied_when = jiffies; - inode_io_list_move_locked(inode, wb, &wb->b_dirty_time); + if (!(inode->i_state & I_FREEING)) { + /* + * If the inode is now fully clean, then it can be safely + * removed from its writeback list (if any). Otherwise the + * flusher threads are responsible for the writeback lists. + */ + if (!(inode->i_state & I_DIRTY_ALL)) + inode_cgwb_move_to_attached(inode, wb); + else if (!(inode->i_state & I_SYNC_QUEUED)) { + if ((inode->i_state & I_DIRTY)) + redirty_tail_locked(inode, wb); + else if (inode->i_state & I_DIRTY_TIME) { + inode->dirtied_when = jiffies; + inode_io_list_move_locked(inode, + wb, + &wb->b_dirty_time); + } } } -- 2.35.1