From patchwork Mon Feb 18 17:04:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Suchanek X-Patchwork-Id: 10818487 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 737DF17FB for ; Mon, 18 Feb 2019 17:05:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 56FE12B27C for ; Mon, 18 Feb 2019 17:05:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 555112B639; Mon, 18 Feb 2019 17:05:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E8B2C2A0A1 for ; Mon, 18 Feb 2019 17:05:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388082AbfBRRFW (ORCPT ); Mon, 18 Feb 2019 12:05:22 -0500 Received: from mx2.suse.de ([195.135.220.15]:56230 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388056AbfBRRFW (ORCPT ); Mon, 18 Feb 2019 12:05:22 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 38564AE1F; Mon, 18 Feb 2019 17:05:21 +0000 (UTC) From: Michal Suchanek To: git@vger.kernel.org Cc: Michal Suchanek , Eric Sunshine , Marketa Calabkova , =?utf-8?b?Tmd1eeG7hW4gVGjDoWkgTmc=?= =?utf-8?b?4buNYyBEdXk=?= , Junio C Hamano Subject: [PATCH 1/2] worktree: fix worktree add race. Date: Mon, 18 Feb 2019 18:04:56 +0100 Message-Id: X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Git runs a stat loop to find a worktree name that's available and then does mkdir on the found name. Turn it to mkdir loop to avoid another invocation of worktree add finding the same free name and creating the directory first. Signed-off-by: Michal Suchanek --- v2: - simplify loop exit condition - exit early if the mkdir fails for reason other than already present worktree - make counter unsigned --- builtin/worktree.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/builtin/worktree.c b/builtin/worktree.c index 3f9907fcc994..85a604cfe98c 100644 --- a/builtin/worktree.c +++ b/builtin/worktree.c @@ -268,10 +268,10 @@ static int add_worktree(const char *path, const char *refname, struct strbuf sb_git = STRBUF_INIT, sb_repo = STRBUF_INIT; struct strbuf sb = STRBUF_INIT; const char *name; - struct stat st; struct child_process cp = CHILD_PROCESS_INIT; struct argv_array child_env = ARGV_ARRAY_INIT; - int counter = 0, len, ret; + unsigned int counter = 0; + int len, ret; struct strbuf symref = STRBUF_INIT; struct commit *commit = NULL; int is_branch = 0; @@ -295,8 +295,12 @@ static int add_worktree(const char *path, const char *refname, if (safe_create_leading_directories_const(sb_repo.buf)) die_errno(_("could not create leading directories of '%s'"), sb_repo.buf); - while (!stat(sb_repo.buf, &st)) { + + while (mkdir(sb_repo.buf, 0777)) { counter++; + if ((errno != EEXIST) || !counter /* overflow */) + die_errno(_("could not create directory of '%s'"), + sb_repo.buf); strbuf_setlen(&sb_repo, len); strbuf_addf(&sb_repo, "%d", counter); } @@ -306,8 +310,6 @@ static int add_worktree(const char *path, const char *refname, atexit(remove_junk); sigchain_push_common(remove_junk_on_signal); - if (mkdir(sb_repo.buf, 0777)) - die_errno(_("could not create directory of '%s'"), sb_repo.buf); junk_git_dir = xstrdup(sb_repo.buf); is_junk = 1;