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 C64BDC77B75 for ; Mon, 22 May 2023 10:25:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232569AbjEVKZN (ORCPT ); Mon, 22 May 2023 06:25:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229890AbjEVKZG (ORCPT ); Mon, 22 May 2023 06:25:06 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13363C5; Mon, 22 May 2023 03:25:04 -0700 (PDT) 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 BA96821A34; Mon, 22 May 2023 10:25:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1684751102; 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; bh=dK4c6jVfMYUnhpgqtCzFKqCJo27Q90EX9O3znFNrfJ8=; b=Bvl8LjGnDdob6XfTE0O/H11rB3dYKccwcJ6uyd1JafLCpggtrml9xk39xpSj5ItgyfMvqk SyYVP7qE0Tvvn3KG8D1vrmLZq24iIInCW/0TLuAbIbmBryVj/Vqn6olLR1nCesBdiXmb6G 2COYy4tGtMqgJ6uqg713Z2FLcqbWxJg= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1684751102; 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; bh=dK4c6jVfMYUnhpgqtCzFKqCJo27Q90EX9O3znFNrfJ8=; b=A9h2RgHLuFWfdKBTk+jbIDMOJUsQzbr5CYAUmlsN7LI5ZoglaxpE8yLh4LJ1ApMCEObDHD pf0HpGp22yxlfuDA== 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 3C7EF13776; Mon, 22 May 2023 10:25:02 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 0PJ8C/5Ca2TFEgAAMHmgww (envelope-from ); Mon, 22 May 2023 10:25:02 +0000 Received: from localhost (brahms.olymp [local]) by brahms.olymp (OpenSMTPD) with ESMTPA id 00fa7886; Mon, 22 May 2023 10:25:00 +0000 (UTC) From: =?UTF-8?q?Lu=C3=ADs=20Henriques?= To: Mark Fasheh , Joel Becker , Joseph Qi Cc: ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org, =?UTF-8?q?Lu=C3=ADs=20Henriques?= , stable@vger.kernel.org Subject: [PATCH] ocfs2: fix use-after-free when unmounting read-only filesystem Date: Mon, 22 May 2023 11:20:30 +0100 Message-Id: <20230522102030.8986-1-lhenriques@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It's trivial to trigger a use-after-free bug in the ocfs2 quotas code using fstest generic/452. After mounting a filesystem as read-only, quotas are suspended and ocfs2_mem_dqinfo is freed through ->ocfs2_local_free_info(). When unmounting the filesystem, an UAF access to the oinfo will eventually cause a crash. Cc: Signed-off-by: Luís Henriques --- fs/ocfs2/super.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c index 0b0e6a132101..988d1c076861 100644 --- a/fs/ocfs2/super.c +++ b/fs/ocfs2/super.c @@ -952,8 +952,10 @@ static void ocfs2_disable_quotas(struct ocfs2_super *osb) for (type = 0; type < OCFS2_MAXQUOTAS; type++) { if (!sb_has_quota_loaded(sb, type)) continue; - oinfo = sb_dqinfo(sb, type)->dqi_priv; - cancel_delayed_work_sync(&oinfo->dqi_sync_work); + if (!sb_has_quota_suspended(sb, type)) { + oinfo = sb_dqinfo(sb, type)->dqi_priv; + cancel_delayed_work_sync(&oinfo->dqi_sync_work); + } inode = igrab(sb->s_dquot.files[type]); /* Turn off quotas. This will remove all dquot structures from * memory and so they will be automatically synced to global