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=-14.1 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=ham 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 5289AC433E1 for ; Mon, 24 Aug 2020 16:45:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2CA9B2067C for ; Mon, 24 Aug 2020 16:45:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598287517; bh=I5sszpnEsWLW9bceSHEeRvrJ/DB70tDxtWUEm34wodg=; h=From:To:Cc:Subject:Date:List-ID:From; b=obwOzMAgV0FP+TR28PVhW/GtFs4iA32tAoQu7YfXHkZIB7PUt5WVQB3/MW8h/jm/T z+omLwkjFWvSMTiKNX3Z9iKzBOafw6s4QkVFsW/ZNCbTWekSHKiex7DMAh8rfzFLej TKg8pwFpauFStVNauOoe70joSmxy3LRk3HGD24IE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728714AbgHXQpK (ORCPT ); Mon, 24 Aug 2020 12:45:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:47586 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728598AbgHXQjh (ORCPT ); Mon, 24 Aug 2020 12:39:37 -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 65DEB22D0B; Mon, 24 Aug 2020 16:39:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598287173; bh=I5sszpnEsWLW9bceSHEeRvrJ/DB70tDxtWUEm34wodg=; h=From:To:Cc:Subject:Date:From; b=Nlm2sMBw37V5t1Sw2QmSN5DXZOQ5t/1ENEcNi9tmOqxV9xN6Eo+urX0QrWWdnjcC/ KqeTG03OoARXnObDYwOOxLj2jEKMaYw+OapqzOWE7EzgSEHb4AbinHfimnc0RfP2VI e6MAGBlNqOyF9/nam3O5hpbydVhMNhgC6hFUDF5g= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Lukas Czerner , Jan Kara , Theodore Ts'o , Sasha Levin , linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 1/8] jbd2: make sure jh have b_transaction set in refile/unfile_buffer Date: Mon, 24 Aug 2020 12:39:24 -0400 Message-Id: <20200824163931.607291-1-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 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: Lukas Czerner [ Upstream commit 24dc9864914eb5813173cfa53313fcd02e4aea7d ] Callers of __jbd2_journal_unfile_buffer() and __jbd2_journal_refile_buffer() assume that the b_transaction is set. In fact if it's not, we can end up with journal_head refcounting errors leading to crash much later that might be very hard to track down. Add asserts to make sure that is the case. We also make sure that b_next_transaction is NULL in __jbd2_journal_unfile_buffer() since the callers expect that as well and we should not get into that stage in this state anyway, leading to problems later on if we do. Tested with fstests. Signed-off-by: Lukas Czerner Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20200617092549.6712-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/jbd2/transaction.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 8de458d64134a..1478512ecab3e 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -1896,6 +1896,9 @@ static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh) */ static void __jbd2_journal_unfile_buffer(struct journal_head *jh) { + J_ASSERT_JH(jh, jh->b_transaction != NULL); + J_ASSERT_JH(jh, jh->b_next_transaction == NULL); + __jbd2_journal_temp_unlink_buffer(jh); jh->b_transaction = NULL; jbd2_journal_put_journal_head(jh); @@ -2443,6 +2446,13 @@ void __jbd2_journal_refile_buffer(struct journal_head *jh) was_dirty = test_clear_buffer_jbddirty(bh); __jbd2_journal_temp_unlink_buffer(jh); + + /* + * b_transaction must be set, otherwise the new b_transaction won't + * be holding jh reference + */ + J_ASSERT_JH(jh, jh->b_transaction != NULL); + /* * We set b_transaction here because b_next_transaction will inherit * our jh reference and thus __jbd2_journal_file_buffer() must not -- 2.25.1