From nobody Fri Dec 19 18:42:01 2025 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 85BC0C38A2D for ; Mon, 24 Oct 2022 13:42:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236054AbiJXNmU (ORCPT ); Mon, 24 Oct 2022 09:42:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236511AbiJXNkc (ORCPT ); Mon, 24 Oct 2022 09:40:32 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66323B2D81; Mon, 24 Oct 2022 05:37:25 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id B149A612A1; Mon, 24 Oct 2022 12:36:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C38FEC433C1; Mon, 24 Oct 2022 12:36:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666615018; bh=RHgpOY34xrHo3qmUkhEOiFA/j5Y4V8+PQcbcKFKYUqE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hgL5KM/4Ce+9ORS8xeZeTGaHs4ol34kDvbPZLpTrgLeoA7d84HqjA5HWAdaofjSzB TvBDz8o92nSrSNB2ywAuuDWeUr9VKFnbWQ3vT4yFaMl0t84KoqiJYHHUK8WIgWY5l0 MUI6gOYJb/7NUQ+dSMJg1HtX3McBInOnCzaMyUhE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, stable@kernel.org, Ye Bin , Jan Kara , Theodore Tso Subject: [PATCH 5.15 090/530] jbd2: fix potential use-after-free in jbd2_fc_wait_bufs Date: Mon, 24 Oct 2022 13:27:14 +0200 Message-Id: <20221024113049.089404719@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024113044.976326639@linuxfoundation.org> References: <20221024113044.976326639@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Ye Bin commit 243d1a5d505d0b0460c9af0ad56ed4a56ef0bebd upstream. In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count which may lead to use-after-free. So judge buffer if uptodate before put buffer head reference count. Cc: stable@kernel.org Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220914100812.1414768-3-yebin10@huawei.com Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman --- fs/jbd2/journal.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -924,16 +924,16 @@ int jbd2_fc_wait_bufs(journal_t *journal for (i =3D j_fc_off - 1; i >=3D j_fc_off - num_blks; i--) { bh =3D journal->j_fc_wbuf[i]; wait_on_buffer(bh); - put_bh(bh); - journal->j_fc_wbuf[i] =3D NULL; /* * Update j_fc_off so jbd2_fc_release_bufs can release remain * buffer head. */ if (unlikely(!buffer_uptodate(bh))) { - journal->j_fc_off =3D i; + journal->j_fc_off =3D i + 1; return -EIO; } + put_bh(bh); + journal->j_fc_wbuf[i] =3D NULL; } =20 return 0;