From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B59B2F531B for ; Sat, 12 Sep 2026 12:32:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789216348; cv=none; b=leH8/43wV0L3qO13JTYEICXW4DEdC1fwFNORpcVpsP4TNcB3Z+qeB+4+ORkyZCMq686SrUUfGrc3oKvTzjvVAOhAP3F4rrQCEqY+UDbXxD2JcPb9Ug1VLP3ZfI+j6+XFL4fl2JVj3uOOHYOkw8qEADntdhfs7FV/DKAlADCn5os= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789216348; c=relaxed/simple; bh=7AjZ9kH9Re1kynDJlWKePkLxkDHCt7Rsw0kLTiGVMY4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=KDFvTBmWqvHTOVApCa+7SHDtVoo0BFCezcGW/Br0JF6Q1jF+XGBOvQGVKCSHX1CW0c1hNGu5EJCElrxcK0yc1i7N0MoVernv+G9kGNQqkPW6ptjTgbewdJob8T0UpBMbQb10Zr+Ruo9jY0gJoWaER0X+J6jJl5xw5MycdESoBzA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZG/Nv0s4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZG/Nv0s4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BD0481F00893; Sat, 12 Sep 2026 12:32:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789216347; bh=WWdsuHVLFdjQKKeBCfs4MxhpYgXm95nxTmEeBZ6wmVY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZG/Nv0s4SDt/IMr16ldHaBnOjfNSCgJW2rGurvqHsApMbhhkXFGKL3pSgw5mA5dIW 9YdmBsyDqZ7fnU8V3rZ6VO1DuMmtnndYn4AMRIFyiAagb2hV6ln4s+bvzZ4Q3mSwmZ dxSBMMJ9U6oLamEwIB4e6yWVuLxwt00VPE8m+sRg6LhFJxhfr2iCRhVJOXaa6YoCtg 87QR9FGxuAWpxCYh6eiYTz4jqX9c+StdfWpmWB/ud+c+34lI+ve7XRKSDyNBuVWLVH lwJ+XSuvxRXxU/aA1cz3vnoPO+mEv0hnjKSvG/UTHkQHTsesig4D5KDEsnHpfNNeks L7BUDhfHOv/YQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Chao Yu , stable@kernel.org, Jaegeuk Kim , Sasha Levin Subject: [PATCH 5.15.y] f2fs: fix to avoid potential deadloop in f2fs_fsync_node_pages() Date: Sat, 12 Sep 2026 08:32:25 -0400 Message-ID: <20260912123225.2618391-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090958-plastic-payee-9f0a@gregkh> References: <2026090958-plastic-payee-9f0a@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Chao Yu [ Upstream commit ce366bfa821ec81dd45bde547ee31e659306cc61 ] There is potential deadloop in race condition: Thread A Thread B - fsync - f2fs_do_sync_file - f2fs_fsync_node_pages - last_fsync_dnode - folio_get(last_folio) - f2fs_setattr - f2fs_truncate - f2fs_truncate_blocks - f2fs_do_truncate_blocks - f2fs_truncate_inode_blocks - truncate_dnode - truncate_node - invalidate_mapping_pages - folio->mapping = NULL - is_node_folio alwasy return false - atomic && !marked is always true, then goto retry Cc: stable@kernel.org Fixes: 608514deba38 ("f2fs: set fsync mark only for the last dnode") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim [ Adapted folio operations to Linux 5.15’s page-based API. ] Signed-off-by: Sasha Levin --- fs/f2fs/node.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index e5a06a65a5398..34a590d500819 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1847,6 +1847,11 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode, f2fs_debug(sbi, "Retry to write fsync mark: ino=%u, idx=%lx", ino, last_page->index); lock_page(last_page); + if (unlikely(last_page->mapping != NODE_MAPPING(sbi))) { + f2fs_put_page(last_page, 1); + ret = -EAGAIN; + goto out; + } f2fs_wait_on_page_writeback(last_page, NODE, true, true); set_page_dirty(last_page); unlock_page(last_page); -- 2.53.0