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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 F10BFC433DF for ; Fri, 21 Aug 2020 17:08:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C842120656 for ; Fri, 21 Aug 2020 17:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598029691; bh=fkPacdxcIDrC+/G09KUx/KOtmzao1YE/gaGyIXvqfxw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FXGiD1DxeaJh82l+wwOh+eliGQT3D7hbdTyH/ps4QudUr3t0tmuS/01PYLO0lf472 zRYmB0ahz3/uHr9of51isj4LlaBe67Omv/bLKWZwfpODXiIvWd2ZhL6qjRuIj2j4HI CSffy7pw/PsUkhhICBg8tDRBj4rD3cxp2sOIgbcg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728892AbgHURIK (ORCPT ); Fri, 21 Aug 2020 13:08:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:49910 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728214AbgHUQSD (ORCPT ); Fri, 21 Aug 2020 12:18:03 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A7DAE22CB2; Fri, 21 Aug 2020 16:17:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598026669; bh=fkPacdxcIDrC+/G09KUx/KOtmzao1YE/gaGyIXvqfxw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gjwpxxyy189HHVyVIAYXBLnH66nQA1OWkQltI4h7NxomxddS02LwHMKkj3Yfd4+l6 he0SkvDZuNYT05w58Tqkvpze7qhbKAk4z8VgDGUrwiDK4S5maQTorvpeC4EoFiOlgt 5m1deriMO45QSq2xB3YKd6e47XbzIl9uQreLEJ54= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Li Guifu , Chao Yu , Jaegeuk Kim , Sasha Levin , linux-f2fs-devel@lists.sourceforge.net Subject: [PATCH AUTOSEL 5.4 35/48] f2fs: fix use-after-free issue Date: Fri, 21 Aug 2020 12:16:51 -0400 Message-Id: <20200821161704.348164-35-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200821161704.348164-1-sashal@kernel.org> References: <20200821161704.348164-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Li Guifu [ Upstream commit 99c787cfd2bd04926f1f553b30bd7dcea2caaba1 ] During umount, f2fs_put_super() unregisters procfs entries after f2fs_destroy_segment_manager(), it may cause use-after-free issue when umount races with procfs accessing, fix it by relocating f2fs_unregister_sysfs(). [Chao Yu: change commit title/message a bit] Signed-off-by: Li Guifu Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/super.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index f4b882ee48ddf..fa461db696e79 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1075,6 +1075,9 @@ static void f2fs_put_super(struct super_block *sb) int i; bool dropped; + /* unregister procfs/sysfs entries in advance to avoid race case */ + f2fs_unregister_sysfs(sbi); + f2fs_quota_off_umount(sb); /* prevent remaining shrinker jobs */ @@ -1138,8 +1141,6 @@ static void f2fs_put_super(struct super_block *sb) kvfree(sbi->ckpt); - f2fs_unregister_sysfs(sbi); - sb->s_fs_info = NULL; if (sbi->s_chksum_driver) crypto_free_shash(sbi->s_chksum_driver); -- 2.25.1