From patchwork Mon Apr 20 22:51:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taylor Blau X-Patchwork-Id: 11500061 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DC520112C for ; Mon, 20 Apr 2020 22:51:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C3873218AC for ; Mon, 20 Apr 2020 22:51:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ttaylorr-com.20150623.gappssmtp.com header.i=@ttaylorr-com.20150623.gappssmtp.com header.b="1tPOIXA2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726709AbgDTWvN (ORCPT ); Mon, 20 Apr 2020 18:51:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726006AbgDTWvM (ORCPT ); Mon, 20 Apr 2020 18:51:12 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7200EC061A0E for ; Mon, 20 Apr 2020 15:51:12 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id 145so3417217pfw.13 for ; Mon, 20 Apr 2020 15:51:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ttaylorr-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=gnSWNBy6IVep98dI2wKXHl4EvBAZZ9WFf+1ofWO7Ioc=; b=1tPOIXA2yErq52egBCIR7/F8/4sGVMehvE4OL6XvRjsnuBS4Fp3HtkbyBcpijKITM8 AcnjR402/Gqme8oa2W980br9xmnrHsvEX/QRrXSQpPFFlESvaFXizMhLmyoIuvGHpr1v 8wfZ9lcLiVsA0WVv7Xiq/2h5Bm6Uo3MU9okilYUcA5UyOpDp34FbeUDkCLoRmZ9AEp6O nSV8ueZ6T/3wXaFMDjo5r7xg+ZJxRgZY5kDcKkvN3d8TOPF1QpaClO/C+lx2Ye/G1Nu4 RIWOJJ64gwk9ypeU1ou5OJRfLS8RDbHsXeVVCVx/2NZZSKd1c72vRnCRpj7UuJDPRF3W aeIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=gnSWNBy6IVep98dI2wKXHl4EvBAZZ9WFf+1ofWO7Ioc=; b=fcwvZPVGCEfc5fz0OU7uvKck09u9ZmFBkjgHRdOpMMor66fKaWphBG0pz+0oNyeHr/ HQ+f6sF7zppzYHisbVMINqqG/G/bmKSMzZotcPhO4uUOhZj+pU0rafeM0yFEuf6J39jL /zFBoal+LsuQ/RqIO5lg6vcutfcWAPjAGbQp6gJQ7ARkTf1HpI2cJkdQEKUEYVhFnyb/ N8dhehMod5XaETmpSwEX6i72UHLxP2klrD816yJmPUSxdP5qKDqkSNqFiCQ8UKiglSuf i2L++FcfyvDFMMt28OIqdOAIVH8d1+B+rcAaKWHmCrtnb8E+jFIZffiI/Fx6TGkV0FpS VtHg== X-Gm-Message-State: AGi0PuYrpUozu/DNHJ1WJkxJrjHNM68jE38EWocgvvehJiGAxRUfrUFK i842ScJEKvc+hQH/OkZo8AjmDX8TE18RmA== X-Google-Smtp-Source: APiQypKjCUXiEZ/f8ShOrbyDGtefiDnxOnPdm9Ple2/TJ0/QLAOqHrHUQdyBuuxdYvtchkTmyC062A== X-Received: by 2002:a62:808d:: with SMTP id j135mr2343255pfd.53.1587423071546; Mon, 20 Apr 2020 15:51:11 -0700 (PDT) Received: from localhost ([8.44.146.30]) by smtp.gmail.com with ESMTPSA id 22sm534415pfb.132.2020.04.20.15.51.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Apr 2020 15:51:10 -0700 (PDT) Date: Mon, 20 Apr 2020 16:51:10 -0600 From: Taylor Blau To: git@vger.kernel.org Cc: dstolee@microsoft.com, mhagger@alum.mit.edu, peff@peff.net Subject: [PATCH 3/3] commit-graph.c: write non-split graphs as read-only Message-ID: <622fd92cee7ccf035c348f64599cdc487b34717b.1587422630.git.me@ttaylorr.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org In the previous commit, Git learned 'hold_lock_file_for_update_mode' to allow the caller to specify the permission bits used when acquiring a temporary file. Use this in the commit-graph machinery for writing a non-split graph to acquire an opened temporary file with permissions read-only permissions to match the split behavior. (In the split case, Git uses 'git_mkstemp_mode' for each of the commit-graph layers with permission bits '0444'). One can notice this discrepancy when moving a non-split graph to be part of a new chain. This causes a commit-graph chain where all layers have read-only permission bits, except for the base layer, which is writable for the current user. Resolve this discrepancy by using the new 'hold_lock_file_for_update_mode' and passing the desired permission bits. Doing so causes some test fallout in t5318 and t6600. In t5318, this occurs in tests that corrupt a commit-graph file by writing into it. For these, 'chmod u+w'-ing the file beforehand resolves the issue. The additional spot in 'corrupt_graph_verify' is necessary because of the extra 'git commit-graph write' beforehand (which *does* rewrite the commit-graph file). In t6600, this is caused by copying a read-only commit-graph file into place and then trying to replace it. For these, make these files writable. Signed-off-by: Taylor Blau --- commit-graph.c | 3 ++- t/t5318-commit-graph.sh | 11 ++++++++++- t/t6600-test-reach.sh | 2 ++ 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/commit-graph.c b/commit-graph.c index f013a84e29..5b5047a7dd 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -1388,7 +1388,8 @@ static int write_commit_graph_file(struct write_commit_graph_context *ctx) f = hashfd(fd, ctx->graph_name); } else { - hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR); + hold_lock_file_for_update_mode(&lk, ctx->graph_name, + LOCK_DIE_ON_ERROR, 0444); fd = lk.tempfile->fd; f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf); } diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh index 9bf920ae17..fb0aae61c3 100755 --- a/t/t5318-commit-graph.sh +++ b/t/t5318-commit-graph.sh @@ -96,6 +96,13 @@ test_expect_success 'write graph' ' graph_read_expect "3" ' +test_expect_success POSIXPERM 'write graph has correct permissions' ' + test_path_is_file $objdir/info/commit-graph && + echo "-r--r--r--" >expect && + test_modebits $objdir/info/commit-graph >actual && + test_cmp expect actual +' + graph_git_behavior 'graph exists' full commits/3 commits/1 test_expect_success 'Add more commits' ' @@ -421,7 +428,8 @@ GRAPH_BYTE_FOOTER=$(($GRAPH_OCTOPUS_DATA_OFFSET + 4 * $NUM_OCTOPUS_EDGES)) corrupt_graph_setup() { cd "$TRASH_DIRECTORY/full" && test_when_finished mv commit-graph-backup $objdir/info/commit-graph && - cp $objdir/info/commit-graph commit-graph-backup + cp $objdir/info/commit-graph commit-graph-backup && + chmod u+w $objdir/info/commit-graph } corrupt_graph_verify() { @@ -435,6 +443,7 @@ corrupt_graph_verify() { fi && git status --short && GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD=true git commit-graph write && + chmod u+w $objdir/info/commit-graph && git commit-graph verify } diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh index b24d850036..475564bee7 100755 --- a/t/t6600-test-reach.sh +++ b/t/t6600-test-reach.sh @@ -51,8 +51,10 @@ test_expect_success 'setup' ' done && git commit-graph write --reachable && mv .git/objects/info/commit-graph commit-graph-full && + chmod u+w commit-graph-full && git show-ref -s commit-5-5 | git commit-graph write --stdin-commits && mv .git/objects/info/commit-graph commit-graph-half && + chmod u+w commit-graph-half && git config core.commitGraph true '