From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 86711327214 for ; Fri, 7 Nov 2025 15:06:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762528013; cv=pass; b=H6YfMt/1270QNubwJFORztM6+C8m4WkRGls8f+9rU97flf4NmMp2473Y5ZVzflB4qpN0aMJGnGftZPwfuBLzi0Cx9yx5y03q01feFQ0HugXd2QmkycJAt5V+7z+GC0C5sKjMiHsj2ikn4jvuebZRwG98afGwee0jv+3nvya4SWk= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762528013; c=relaxed/simple; bh=isQFpDh8PeVrYxJdmk6DL9IjMdYu64KGPdHj6ojrwtw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rJwiHN41QebEkXZIIWnD2lMfzQDcrAMeTGzy7/Gkb9YGJVBy1SFWQQJBlYBSAy0tHolLvLGUJFWS5DJIzqgSSKRNqCp0BsPhdOyCurH3LQpqVCIQ8YvMNEUGhfto+ndOP6LJPYYLUYKA0cBEwm6tZvMgSmQF/1djrzC9lv9FwBM= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=adrian.ratiu@collabora.com header.b=TYXWhYpz; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=adrian.ratiu@collabora.com header.b="TYXWhYpz" ARC-Seal: i=1; a=rsa-sha256; t=1762527993; cv=none; d=zohomail.com; s=zohoarc; b=FyoBO9iW6RMWZ597rcnyhUGJ3zput17PUxV8L+ckucDugYsrQOZk7IXElMiyYHU6EDnLv4d22v/wKU+3JQ2RpIiX8uYk6yFf/y/J/H9HQKyGYlnGG7eMM4v1No93Hga1/xOu8Omt3C4zFtgum4t6dPt6RwapEpa8hUQCVXhQ3IA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1762527993; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=0jUmVtNEfVsuiDZQz2swenJCklF9Qot/fpEQNKhMoXQ=; b=OfGVAzi1czC4dzwkLUEJzCs9fBs0lnLdZCiU0yqVUxJdv51tzwC+GrXAZNnmLkh9f+XzR+KuTB0fZoTYrExCQ8wdc3qqkGOXpuPCE+3V4RjTjrdwa1s/wfahWzfhYXJ+yJ3I70fxLAI/EYHXhliCBmUdt8aQnX7TRw/+946k/Wc= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=adrian.ratiu@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1762527993; s=zohomail; d=collabora.com; i=adrian.ratiu@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=0jUmVtNEfVsuiDZQz2swenJCklF9Qot/fpEQNKhMoXQ=; b=TYXWhYpz7y1uIRHppThXiZhB9YFpDC17Mau/Hik+PbLgnrnmP+wWNNL4ko7OSxcR RFgilnuMUHm0QZQGgat8HByhca7amZ7zcTBHx+qys6bUY99nKezFLKWSOS4kWmcXYhj f1+Nu9vWgoUJ3sjTj/Nrxlxhv0Z3bg+U0ZDUTGMY= Received: by mx.zohomail.com with SMTPS id 1762527990621571.8269921605121; Fri, 7 Nov 2025 07:06:30 -0800 (PST) From: Adrian Ratiu To: git@vger.kernel.org Cc: Emily Shaffer , Rodrigo Damazio Bovendorp , Jeff King , Junio C Hamano , Aaron Schrab , Jonathan Nieder , Patrick Steinhardt , Josh Steadmon , Ben Knoble , Phillip Wood , Adrian Ratiu Subject: [PATCH v4 4/4] submodule: fix case-folding gitdir filesystem colisions Date: Fri, 7 Nov 2025 17:05:47 +0200 Message-ID: <20251107150547.3272180-5-adrian.ratiu@collabora.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251107150547.3272180-1-adrian.ratiu@collabora.com> References: <20250816213642.3517822-1-adrian.ratiu@collabora.com> <20251107150547.3272180-1-adrian.ratiu@collabora.com> Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External Add a new check in validate_submodule_git_dir() to detect and prevent case-folding filesystem colisions. When this new check is triggered, a stricter casefolding aware URI encoding is used to percent-encode uppercase characters, e.g. Foo becomes %46oo. By using this check/retry mechanism the uppercase encoding is only applied when necessary, so case-sensitive filesystems are not affected. Signed-off-by: Adrian Ratiu --- submodule.c | 47 +++++++++++++++++++++++++++++++++-- t/t7425-submodule-encoding.sh | 15 +++++++++++ url.c | 12 +++++++++ url.h | 1 + 4 files changed, 73 insertions(+), 2 deletions(-) diff --git a/submodule.c b/submodule.c index ceaff0c1aa..ecbffac2c6 100644 --- a/submodule.c +++ b/submodule.c @@ -2280,7 +2280,7 @@ int validate_submodule_git_dir(char *git_dir, const char *submodule_name) size_t len = strlen(git_dir), suffix_len = strlen(submodule_name); char *p = git_dir + len - suffix_len; bool suffixes_match = !strcmp(p, submodule_name); - int ret = 0; + int ret = 0, config_ignorecase = 0; /* * We prevent the contents of sibling submodules' git directories to @@ -2318,6 +2318,42 @@ int validate_submodule_git_dir(char *git_dir, const char *submodule_name) if (p && strchr(p, '/') != NULL) return error("submodule gitdir name '%s' contains unexpected '/'", p); + /* Prevent conflicts on case-folding filesystems */ + repo_config_get_bool(the_repository, "core.ignorecase", &config_ignorecase); + if (ignore_case || config_ignorecase) { + char *lower_gitdir = xstrdup(git_dir); + char *module_name = find_last_submodule_name(lower_gitdir); + + if (module_name) { + for (p = module_name; *p; p++) + *p = tolower(*p); + + /* + * If lower path is different and already exists, check for collision. + * Intentionally double-check to eliminate false-positives. + */ + if (strcmp(lower_gitdir, git_dir) && is_git_directory(lower_gitdir)) { + char *canonical = real_pathdup(git_dir, 0); + if (canonical) { + struct strbuf norm_git_dir = STRBUF_INIT; + strbuf_addstr(&norm_git_dir, git_dir); + strbuf_normalize_path(&norm_git_dir); + + if (strcmp(canonical, norm_git_dir.buf)) + ret = error(_("submodule git dir '%s' " + "collides with '%s'"), + canonical, norm_git_dir.buf); + + strbuf_release(&norm_git_dir); + FREE_AND_NULL(canonical); + } + } + } + + FREE_AND_NULL(lower_gitdir); + return ret; + } + return 0; } @@ -2653,13 +2689,20 @@ void submodule_name_to_gitdir(struct strbuf *buf, struct repository *r, if (!validate_and_set_submodule_gitdir(buf, submodule_name)) return; - /* Case 2: Try URI-safe (RFC3986) encoding first, this fixes nested gitdirs */ + /* Case 2.1: Try URI-safe (RFC3986) encoding first, this fixes nested gitdirs */ strbuf_reset(buf); repo_git_path_append(r, buf, "modules/"); strbuf_addstr_urlencode(buf, submodule_name, is_rfc3986_unreserved); if (!validate_and_set_submodule_gitdir(buf, submodule_name)) return; + /* Case 2.2: Try extended uppercase URI (RFC3986) encoding, to fix case-folding */ + strbuf_reset(buf); + repo_git_path_append(r, buf, "modules/"); + strbuf_addstr_urlencode(buf, submodule_name, is_casefolding_rfc3986_unreserved); + if (!validate_and_set_submodule_gitdir(buf, submodule_name)) + return; + /* Case 3: error out */ die(_("Cannot construct a valid gitdir path for submodule '%s': " "please set a unique git config for 'submodule.%s.gitdir'."), diff --git a/t/t7425-submodule-encoding.sh b/t/t7425-submodule-encoding.sh index a42d358f5b..f92b3e6338 100755 --- a/t/t7425-submodule-encoding.sh +++ b/t/t7425-submodule-encoding.sh @@ -143,4 +143,19 @@ test_expect_success 'submodule git dir nesting detection must work with parallel verify_submodule_gitdir_path clone_parallel hippo/hooks modules/hippo%2fhooks ' +test_expect_success 'verify case-folding conflict is correctly encoded' ' + git clone -c extensions.submoduleEncoding=true -c core.ignoreCase=true main cloned-folding && + ( + cd cloned-folding && + + git submodule add ../new-sub "folding" && + test_commit lowercase && + + git submodule add ../new-sub "FoldinG" && + test_commit uppercase + ) && + verify_submodule_gitdir_path cloned-folding "folding" "modules/folding" && + verify_submodule_gitdir_path cloned-folding "FoldinG" "modules/%46oldin%47" +' + test_done diff --git a/url.c b/url.c index 0fb1859b28..057e6e5c6e 100644 --- a/url.c +++ b/url.c @@ -14,6 +14,18 @@ int is_rfc3986_unreserved(char ch) ch == '-' || ch == '_' || ch == '.' || ch == '~'; } +/* + * This is a variant of is_rfc3986_unreserved() that treats uppercase + * letters as "reserved". This forces them to be percent-encoded, allowing + * 'Foo' (%46oo) and 'foo' (foo) to be distinct on case-folding filesystems. + */ +int is_casefolding_rfc3986_unreserved(char c) +{ + return (c >= 'a' && c <= 'z') || + (c >= '0' && c <= '9') || + c == '-' || c == '.' || c == '_' || c == '~'; +} + int is_urlschemechar(int first_flag, int ch) { /* diff --git a/url.h b/url.h index 131a262066..92e3c63514 100644 --- a/url.h +++ b/url.h @@ -22,5 +22,6 @@ void end_url_with_slash(struct strbuf *buf, const char *url); void str_end_url_with_slash(const char *url, char **dest); int is_rfc3986_unreserved(char ch); +int is_casefolding_rfc3986_unreserved(char c); #endif /* URL_H */ -- 2.51.0