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-rw-r--r--Documentation/git-upload-pack.txt31
-rw-r--r--Documentation/git.txt31
-rw-r--r--builtin/submodule--helper.c86
-rw-r--r--builtin/upload-pack.c2
-rw-r--r--cache.h12
-rw-r--r--path.c2
-rw-r--r--promisor-remote.c10
-rw-r--r--read-cache.c72
-rw-r--r--setup.c21
-rw-r--r--submodule.c89
-rw-r--r--submodule.h5
-rwxr-xr-xt/t0000-basic.sh28
-rwxr-xr-xt/t0411-clone-from-partial.sh78
-rwxr-xr-xt/t7406-submodule-update.sh48
-rwxr-xr-xt/t7423-submodule-symlinks.sh67
-rwxr-xr-xt/t7450-bad-git-dotfiles.sh34
16 files changed, 559 insertions, 57 deletions
diff --git a/Documentation/git-upload-pack.txt b/Documentation/git-upload-pack.txt
index b656b47567..1d30a4f6b4 100644
--- a/Documentation/git-upload-pack.txt
+++ b/Documentation/git-upload-pack.txt
@@ -55,6 +55,37 @@ ENVIRONMENT
admins may need to configure some transports to allow this
variable to be passed. See the discussion in linkgit:git[1].
+`GIT_NO_LAZY_FETCH`::
+ When cloning or fetching from a partial repository (i.e., one
+ itself cloned with `--filter`), the server-side `upload-pack`
+ may need to fetch extra objects from its upstream in order to
+ complete the request. By default, `upload-pack` will refuse to
+ perform such a lazy fetch, because `git fetch` may run arbitrary
+ commands specified in configuration and hooks of the source
+ repository (and `upload-pack` tries to be safe to run even in
+ untrusted `.git` directories).
++
+This is implemented by having `upload-pack` internally set the
+`GIT_NO_LAZY_FETCH` variable to `1`. If you want to override it
+(because you are fetching from a partial clone, and you are sure
+you trust it), you can explicitly set `GIT_NO_LAZY_FETCH` to
+`0`.
+
+SECURITY
+--------
+
+Most Git commands should not be run in an untrusted `.git` directory
+(see the section `SECURITY` in linkgit:git[1]). `upload-pack` tries to
+avoid any dangerous configuration options or hooks from the repository
+it's serving, making it safe to clone an untrusted directory and run
+commands on the resulting clone.
+
+For an extra level of safety, you may be able to run `upload-pack` as an
+alternate user. The details will be platform dependent, but on many
+systems you can run:
+
+ git clone --no-local --upload-pack='sudo -u nobody git-upload-pack' ...
+
SEE ALSO
--------
linkgit:gitnamespaces[7]
diff --git a/Documentation/git.txt b/Documentation/git.txt
index 1d33e083ab..d2969461a4 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -1032,6 +1032,37 @@ The index is also capable of storing multiple entries (called "stages")
for a given pathname. These stages are used to hold the various
unmerged version of a file when a merge is in progress.
+SECURITY
+--------
+
+Some configuration options and hook files may cause Git to run arbitrary
+shell commands. Because configuration and hooks are not copied using
+`git clone`, it is generally safe to clone remote repositories with
+untrusted content, inspect them with `git log`, and so on.
+
+However, it is not safe to run Git commands in a `.git` directory (or
+the working tree that surrounds it) when that `.git` directory itself
+comes from an untrusted source. The commands in its config and hooks
+are executed in the usual way.
+
+By default, Git will refuse to run when the repository is owned by
+someone other than the user running the command. See the entry for
+`safe.directory` in linkgit:git-config[1]. While this can help protect
+you in a multi-user environment, note that you can also acquire
+untrusted repositories that are owned by you (for example, if you
+extract a zip file or tarball from an untrusted source). In such cases,
+you'd need to "sanitize" the untrusted repository first.
+
+If you have an untrusted `.git` directory, you should first clone it
+with `git clone --no-local` to obtain a clean copy. Git does restrict
+the set of options and hooks that will be run by `upload-pack`, which
+handles the server side of a clone or fetch, but beware that the
+surface area for attack against `upload-pack` is large, so this does
+carry some risk. The safest thing is to serve the repository as an
+unprivileged user (either via linkgit:git-daemon[1], ssh, or using
+other tools to change user ids). See the discussion in the `SECURITY`
+section of linkgit:git-upload-pack[1].
+
FURTHER DOCUMENTATION
---------------------
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 6743fb27bd..941afe1568 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -294,6 +294,9 @@ static void runcommand_in_submodule_cb(const struct cache_entry *list_item,
struct child_process cp = CHILD_PROCESS_INIT;
char *displaypath;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
displaypath = get_submodule_displaypath(path, info->prefix);
sub = submodule_from_path(the_repository, null_oid(), path);
@@ -620,6 +623,9 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
.free_removed_argv_elements = 1,
};
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
if (!submodule_from_path(the_repository, null_oid(), path))
die(_("no submodule mapping found in .gitmodules for path '%s'"),
path);
@@ -1220,6 +1226,9 @@ static void sync_submodule(const char *path, const char *prefix,
if (!is_submodule_active(the_repository, path))
return;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
sub = submodule_from_path(the_repository, null_oid(), path);
if (sub && sub->url) {
@@ -1360,6 +1369,9 @@ static void deinit_submodule(const char *path, const char *prefix,
struct strbuf sb_config = STRBUF_INIT;
char *sub_git_dir = xstrfmt("%s/.git", path);
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
sub = submodule_from_path(the_repository, null_oid(), path);
if (!sub || !sub->name)
@@ -1641,16 +1653,42 @@ static char *clone_submodule_sm_gitdir(const char *name)
return sm_gitdir;
}
+static int dir_contains_only_dotgit(const char *path)
+{
+ DIR *dir = opendir(path);
+ struct dirent *e;
+ int ret = 1;
+
+ if (!dir)
+ return 0;
+
+ e = readdir_skip_dot_and_dotdot(dir);
+ if (!e)
+ ret = 0;
+ else if (strcmp(DEFAULT_GIT_DIR_ENVIRONMENT, e->d_name) ||
+ (e = readdir_skip_dot_and_dotdot(dir))) {
+ error("unexpected item '%s' in '%s'", e->d_name, path);
+ ret = 0;
+ }
+
+ closedir(dir);
+ return ret;
+}
+
static int clone_submodule(const struct module_clone_data *clone_data,
struct string_list *reference)
{
char *p;
char *sm_gitdir = clone_submodule_sm_gitdir(clone_data->name);
char *sm_alternate = NULL, *error_strategy = NULL;
+ struct stat st;
struct child_process cp = CHILD_PROCESS_INIT;
const char *clone_data_path = clone_data->path;
char *to_free = NULL;
+ if (validate_submodule_path(clone_data_path) < 0)
+ exit(128);
+
if (!is_absolute_path(clone_data->path))
clone_data_path = to_free = xstrfmt("%s/%s", get_git_work_tree(),
clone_data->path);
@@ -1660,6 +1698,10 @@ static int clone_submodule(const struct module_clone_data *clone_data,
"git dir"), sm_gitdir);
if (!file_exists(sm_gitdir)) {
+ if (clone_data->require_init && !stat(clone_data_path, &st) &&
+ !is_empty_dir(clone_data_path))
+ die(_("directory not empty: '%s'"), clone_data_path);
+
if (safe_create_leading_directories_const(sm_gitdir) < 0)
die(_("could not create directory '%s'"), sm_gitdir);
@@ -1704,10 +1746,18 @@ static int clone_submodule(const struct module_clone_data *clone_data,
if(run_command(&cp))
die(_("clone of '%s' into submodule path '%s' failed"),
clone_data->url, clone_data_path);
+
+ if (clone_data->require_init && !stat(clone_data_path, &st) &&
+ !dir_contains_only_dotgit(clone_data_path)) {
+ char *dot_git = xstrfmt("%s/.git", clone_data_path);
+ unlink(dot_git);
+ free(dot_git);
+ die(_("directory not empty: '%s'"), clone_data_path);
+ }
} else {
char *path;
- if (clone_data->require_init && !access(clone_data_path, X_OK) &&
+ if (clone_data->require_init && !stat(clone_data_path, &st) &&
!is_empty_dir(clone_data_path))
die(_("directory not empty: '%s'"), clone_data_path);
if (safe_create_leading_directories_const(clone_data_path) < 0)
@@ -1717,6 +1767,23 @@ static int clone_submodule(const struct module_clone_data *clone_data,
free(path);
}
+ /*
+ * We already performed this check at the beginning of this function,
+ * before cloning the objects. This tries to detect racy behavior e.g.
+ * in parallel clones, where another process could easily have made the
+ * gitdir nested _after_ it was created.
+ *
+ * To prevent further harm coming from this unintentionally-nested
+ * gitdir, let's disable it by deleting the `HEAD` file.
+ */
+ if (validate_submodule_git_dir(sm_gitdir, clone_data->name) < 0) {
+ char *head = xstrfmt("%s/HEAD", sm_gitdir);
+ unlink(head);
+ free(head);
+ die(_("refusing to create/use '%s' in another submodule's "
+ "git dir"), sm_gitdir);
+ }
+
connect_work_tree_and_git_dir(clone_data_path, sm_gitdir, 0);
p = git_pathdup_submodule(clone_data_path, "config");
@@ -2490,6 +2557,9 @@ static int update_submodule(struct update_data *update_data)
{
int ret;
+ if (validate_submodule_path(update_data->sm_path) < 0)
+ return -1;
+
ret = determine_submodule_update_strategy(the_repository,
update_data->just_cloned,
update_data->sm_path,
@@ -2597,12 +2667,21 @@ static int update_submodules(struct update_data *update_data)
for (i = 0; i < suc.update_clone_nr; i++) {
struct update_clone_data ucd = suc.update_clone[i];
- int code;
+ int code = 128;
oidcpy(&update_data->oid, &ucd.oid);
update_data->just_cloned = ucd.just_cloned;
update_data->sm_path = ucd.sub->path;
+ /*
+ * Verify that the submodule path does not contain any
+ * symlinks; if it does, it might have been tampered with.
+ * TODO: allow exempting it via
+ * `safe.submodule.path` or something
+ */
+ if (validate_submodule_path(update_data->sm_path) < 0)
+ goto fail;
+
code = ensure_core_worktree(update_data->sm_path);
if (code)
goto fail;
@@ -3309,6 +3388,9 @@ static int module_add(int argc, const char **argv, const char *prefix)
normalize_path_copy(add_data.sm_path, add_data.sm_path);
strip_dir_trailing_slashes(add_data.sm_path);
+ if (validate_submodule_path(add_data.sm_path) < 0)
+ exit(128);
+
die_on_index_match(add_data.sm_path, force);
die_on_repo_without_commits(add_data.sm_path);
diff --git a/builtin/upload-pack.c b/builtin/upload-pack.c
index 25b69da2bf..f446ff04f6 100644
--- a/builtin/upload-pack.c
+++ b/builtin/upload-pack.c
@@ -35,6 +35,8 @@ int cmd_upload_pack(int argc, const char **argv, const char *prefix)
packet_trace_identity("upload-pack");
read_replace_refs = 0;
+ /* TODO: This should use NO_LAZY_FETCH_ENVIRONMENT */
+ xsetenv("GIT_NO_LAZY_FETCH", "1", 0);
argc = parse_options(argc, argv, prefix, options, upload_pack_usage, 0);
diff --git a/cache.h b/cache.h
index fcf49706ad..a46a3e4b6b 100644
--- a/cache.h
+++ b/cache.h
@@ -606,6 +606,18 @@ void set_git_work_tree(const char *tree);
#define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
+/*
+ * Check if a repository is safe and die if it is not, by verifying the
+ * ownership of the worktree (if any), the git directory, and the gitfile (if
+ * any).
+ *
+ * Exemptions for known-safe repositories can be added via `safe.directory`
+ * config settings; for non-bare repositories, their worktree needs to be
+ * added, for bare ones their git directory.
+ */
+void die_upon_dubious_ownership(const char *gitfile, const char *worktree,
+ const char *gitdir);
+
void setup_work_tree(void);
/*
* Find the commondir and gitdir of the repository that contains the current
diff --git a/path.c b/path.c
index 492e17ad12..d61f70e87d 100644
--- a/path.c
+++ b/path.c
@@ -840,6 +840,7 @@ const char *enter_repo(const char *path, int strict)
if (!suffix[i])
return NULL;
gitfile = read_gitfile(used_path.buf);
+ die_upon_dubious_ownership(gitfile, NULL, used_path.buf);
if (gitfile) {
strbuf_reset(&used_path);
strbuf_addstr(&used_path, gitfile);
@@ -850,6 +851,7 @@ const char *enter_repo(const char *path, int strict)
}
else {
const char *gitfile = read_gitfile(path);
+ die_upon_dubious_ownership(gitfile, NULL, path);
if (gitfile)
path = gitfile;
if (chdir(path))
diff --git a/promisor-remote.c b/promisor-remote.c
index faa7612941..550a38f752 100644
--- a/promisor-remote.c
+++ b/promisor-remote.c
@@ -20,6 +20,16 @@ static int fetch_objects(struct repository *repo,
int i;
FILE *child_in;
+ /* TODO: This should use NO_LAZY_FETCH_ENVIRONMENT */
+ if (git_env_bool("GIT_NO_LAZY_FETCH", 0)) {
+ static int warning_shown;
+ if (!warning_shown) {
+ warning_shown = 1;
+ warning(_("lazy fetching disabled; some objects may not be available"));
+ }
+ return -1;
+ }
+
child.git_cmd = 1;
child.in = -1;
if (repo != the_repository)
diff --git a/read-cache.c b/read-cache.c
index 46f5e497b1..383ec6d366 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1186,19 +1186,32 @@ static int has_dir_name(struct index_state *istate,
istate->cache[istate->cache_nr - 1]->name,
&len_eq_last);
if (cmp_last > 0) {
- if (len_eq_last == 0) {
+ if (name[len_eq_last] != '/') {
/*
* The entry sorts AFTER the last one in the
- * index and their paths have no common prefix,
- * so there cannot be a F/D conflict.
+ * index.
+ *
+ * If there were a conflict with "file", then our
+ * name would start with "file/" and the last index
+ * entry would start with "file" but not "file/".
+ *
+ * The next character after common prefix is
+ * not '/', so there can be no conflict.
*/
return retval;
} else {
/*
* The entry sorts AFTER the last one in the
- * index, but has a common prefix. Fall through
- * to the loop below to disect the entry's path
- * and see where the difference is.
+ * index, and the next character after common
+ * prefix is '/'.
+ *
+ * Either the last index entry is a file in
+ * conflict with this entry, or it has a name
+ * which sorts between this entry and the
+ * potential conflicting file.
+ *
+ * In both cases, we fall through to the loop
+ * below and let the regular search code handle it.
*/
}
} else if (cmp_last == 0) {
@@ -1222,53 +1235,6 @@ static int has_dir_name(struct index_state *istate,
}
len = slash - name;
- if (cmp_last > 0) {
- /*
- * (len + 1) is a directory boundary (including
- * the trailing slash). And since the loop is
- * decrementing "slash", the first iteration is
- * the longest directory prefix; subsequent
- * iterations consider parent directories.
- */
-
- if (len + 1 <= len_eq_last) {
- /*
- * The directory prefix (including the trailing
- * slash) also appears as a prefix in the last
- * entry, so the remainder cannot collide (because
- * strcmp said the whole path was greater).
- *
- * EQ: last: xxx/A
- * this: xxx/B
- *
- * LT: last: xxx/file_A
- * this: xxx/file_B
- */
- return retval;
- }
-
- if (len > len_eq_last) {
- /*
- * This part of the directory prefix (excluding
- * the trailing slash) is longer than the known
- * equal portions, so this sub-directory cannot
- * collide with a file.
- *
- * GT: last: xxxA
- * this: xxxB/file
- */
- return retval;
- }
-
- /*
- * This is a possible collision. Fall through and
- * let the regular search code handle it.
- *
- * last: xxx
- * this: xxx/file
- */
- }
-
pos = index_name_stage_pos(istate, name, len, stage, EXPAND_SPARSE);
if (pos >= 0) {
/*
diff --git a/setup.c b/setup.c
index cefd5f63c4..9d401ae4c8 100644
--- a/setup.c
+++ b/setup.c
@@ -1165,6 +1165,27 @@ static int ensure_valid_ownership(const char *gitfile,
return data.is_safe;
}
+void die_upon_dubious_ownership(const char *gitfile, const char *worktree,
+ const char *gitdir)
+{
+ struct strbuf report = STRBUF_INIT, quoted = STRBUF_INIT;
+ const char *path;
+
+ if (ensure_valid_ownership(gitfile, worktree, gitdir, &report))
+ return;
+
+ strbuf_complete(&report, '\n');
+ path = gitfile ? gitfile : gitdir;
+ sq_quote_buf_pretty(&quoted, path);
+
+ die(_("detected dubious ownership in repository at '%s'\n"
+ "%s"
+ "To add an exception for this directory, call:\n"
+ "\n"
+ "\tgit config --global --add safe.directory %s"),
+ path, report.buf, quoted.buf);
+}
+
static int allowed_bare_repo_cb(const char *key, const char *value, void *d)
{
enum allowed_bare_repo *allowed_bare_repo = d;
diff --git a/submodule.c b/submodule.c
index fae24ef34a..0b87ae6340 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1005,6 +1005,9 @@ static int submodule_has_commits(struct repository *r,
.super_oid = super_oid
};
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
oid_array_for_each_unique(commits, check_has_commit, &has_commit);
if (has_commit.result) {
@@ -1127,6 +1130,9 @@ static int push_submodule(const char *path,
const struct string_list *push_options,
int dry_run)
{
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
struct child_process cp = CHILD_PROCESS_INIT;
strvec_push(&cp.args, "push");
@@ -1176,6 +1182,9 @@ static void submodule_push_check(const char *path, const char *head,
struct child_process cp = CHILD_PROCESS_INIT;
int i;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
strvec_push(&cp.args, "submodule--helper");
strvec_push(&cp.args, "push-check");
strvec_push(&cp.args, head);
@@ -1507,6 +1516,9 @@ static struct fetch_task *fetch_task_create(struct submodule_parallel_fetch *spf
struct fetch_task *task = xmalloc(sizeof(*task));
memset(task, 0, sizeof(*task));
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
task->sub = submodule_from_path(spf->r, treeish_name, path);
if (!task->sub) {
@@ -1879,6 +1891,9 @@ unsigned is_submodule_modified(const char *path, int ignore_untracked)
const char *git_dir;
int ignore_cp_exit_code = 0;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
strbuf_addf(&buf, "%s/.git", path);
git_dir = read_gitfile(buf.buf);
if (!git_dir)
@@ -1955,6 +1970,9 @@ int submodule_uses_gitfile(const char *path)
struct strbuf buf = STRBUF_INIT;
const char *git_dir;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
strbuf_addf(&buf, "%s/.git", path);
git_dir = read_gitfile(buf.buf);
if (!git_dir) {
@@ -1994,6 +2012,9 @@ int bad_to_remove_submodule(const char *path, unsigned flags)
struct strbuf buf = STRBUF_INIT;
int ret = 0;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
if (!file_exists(path) || is_empty_dir(path))
return 0;
@@ -2044,6 +2065,9 @@ void submodule_unset_core_worktree(const struct submodule *sub)
{
struct strbuf config_path = STRBUF_INIT;
+ if (validate_submodule_path(sub->path) < 0)
+ exit(128);
+
submodule_name_to_gitdir(&config_path, the_repository, sub->name);
strbuf_addstr(&config_path, "/config");
@@ -2066,6 +2090,9 @@ static int submodule_has_dirty_index(const struct submodule *sub)
{
struct child_process cp = CHILD_PROCESS_INIT;
+ if (validate_submodule_path(sub->path) < 0)
+ exit(128);
+
prepare_submodule_repo_env(&cp.env);
cp.git_cmd = 1;
@@ -2083,6 +2110,10 @@ static int submodule_has_dirty_index(const struct submodule *sub)
static void submodule_reset_index(const char *path)
{
struct child_process cp = CHILD_PROCESS_INIT;
+
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
prepare_submodule_repo_env(&cp.env);
cp.git_cmd = 1;
@@ -2146,10 +2177,27 @@ int submodule_move_head(const char *path,
if (old_head) {
if (!submodule_uses_gitfile(path))
absorb_git_dir_into_superproject(path);
+ else {
+ char *dotgit = xstrfmt("%s/.git", path);
+ char *git_dir = xstrdup(read_gitfile(dotgit));
+
+ free(dotgit);
+ if (validate_submodule_git_dir(git_dir,
+ sub->name) < 0)
+ die(_("refusing to create/use '%s' in "
+ "another submodule's git dir"),
+ git_dir);
+ free(git_dir);
+ }
} else {
struct strbuf gitdir = STRBUF_INIT;
submodule_name_to_gitdir(&gitdir, the_repository,
sub->name);
+ if (validate_submodule_git_dir(gitdir.buf,
+ sub->name) < 0)
+ die(_("refusing to create/use '%s' in another "
+ "submodule's git dir"),
+ gitdir.buf);
connect_work_tree_and_git_dir(path, gitdir.buf, 0);
strbuf_release(&gitdir);
@@ -2270,6 +2318,34 @@ int validate_submodule_git_dir(char *git_dir, const char *submodule_name)
return 0;
}
+int validate_submodule_path(const char *path)
+{
+ char *p = xstrdup(path);
+ struct stat st;
+ int i, ret = 0;
+ char sep;
+
+ for (i = 0; !ret && p[i]; i++) {
+ if (!is_dir_sep(p[i]))
+ continue;
+
+ sep = p[i];
+ p[i] = '\0';
+ /* allow missing components, but no symlinks */
+ ret = lstat(p, &st) || !S_ISLNK(st.st_mode) ? 0 : -1;
+ p[i] = sep;
+ if (ret)
+ error(_("expected '%.*s' in submodule path '%s' not to "
+ "be a symbolic link"), i, p, p);
+ }
+ if (!lstat(p, &st) && S_ISLNK(st.st_mode))
+ ret = error(_("expected submodule path '%s' not to be a "
+ "symbolic link"), p);
+ free(p);
+ return ret;
+}
+
+
/*
* Embeds a single submodules git directory into the superprojects git dir,
* non recursively.
@@ -2280,6 +2356,9 @@ static void relocate_single_git_dir_into_superproject(const char *path)
struct strbuf new_gitdir = STRBUF_INIT;
const struct submodule *sub;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
if (submodule_uses_worktrees(path))
die(_("relocate_gitdir for submodule '%s' with "
"more than one worktree not supported"), path);
@@ -2320,6 +2399,9 @@ static void absorb_git_dir_into_superproject_recurse(const char *path)
struct child_process cp = CHILD_PROCESS_INIT;
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
cp.dir = path;
cp.git_cmd = 1;
cp.no_stdin = 1;
@@ -2342,6 +2424,10 @@ void absorb_git_dir_into_superproject(const char *path)
int err_code;
const char *sub_git_dir;
struct strbuf gitdir = STRBUF_INIT;
+
+ if (validate_submodule_path(path) < 0)
+ exit(128);
+
strbuf_addf(&gitdir, "%s/.git", path);
sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
@@ -2484,6 +2570,9 @@ int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
const char *git_dir;
int ret = 0;
+ if (validate_submodule_path(submodule) < 0)
+ exit(128);
+
strbuf_reset(buf);
strbuf_addstr(buf, submodule);
strbuf_complete(buf, '/');
diff --git a/submodule.h b/submodule.h
index b52a4ff1e7..fb770f1687 100644
--- a/submodule.h
+++ b/submodule.h
@@ -148,6 +148,11 @@ void submodule_name_to_gitdir(struct strbuf *buf, struct repository *r,
*/
int validate_submodule_git_dir(char *git_dir, const char *submodule_name);
+/*
+ * Make sure that the given submodule path does not follow symlinks.
+ */
+int validate_submodule_path(const char *path);
+
#define SUBMODULE_MOVE_HEAD_DRY_RUN (1<<0)
#define SUBMODULE_MOVE_HEAD_FORCE (1<<1)
int submodule_move_head(const char *path,
diff --git a/t/t0000-basic.sh b/t/t0000-basic.sh
index 502b4bcf9e..2ba219b18b 100755
--- a/t/t0000-basic.sh
+++ b/t/t0000-basic.sh
@@ -1200,6 +1200,34 @@ test_expect_success 'very long name in the index handled sanely' '
test $len = 4098
'
+# D/F conflict checking uses an optimization when adding to the end.
+# make sure it does not get confused by `a-` sorting _between_
+# `a` and `a/`.
+test_expect_success 'more update-index D/F conflicts' '
+ # empty the index to make sure our entry is last
+ git read-tree --empty &&
+ cacheinfo=100644,$(test_oid empty_blob) &&
+ git update-index --add --cacheinfo $cacheinfo,path5/a &&
+
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/file &&
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/b/file &&
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/b/c/file &&
+
+ # "a-" sorts between "a" and "a/"
+ git update-index --add --cacheinfo $cacheinfo,path5/a- &&
+
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/file &&
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/b/file &&
+ test_must_fail git update-index --add --cacheinfo $cacheinfo,path5/a/b/c/file &&
+
+ cat >expected <<-\EOF &&
+ path5/a
+ path5/a-
+ EOF
+ git ls-files >actual &&
+ test_cmp expected actual
+'
+
test_expect_success 'test_must_fail on a failing git command' '
test_must_fail git notacommand
'
diff --git a/t/t0411-clone-from-partial.sh b/t/t0411-clone-from-partial.sh
new file mode 100755
index 0000000000..b3d6ddc4bc
--- /dev/null
+++ b/t/t0411-clone-from-partial.sh
@@ -0,0 +1,78 @@
+#!/bin/sh
+
+test_description='check that local clone does not fetch from promisor remotes'
+
+. ./test-lib.sh
+
+test_expect_success 'create evil repo' '
+ git init tmp &&
+ test_commit -C tmp a &&
+ git -C tmp config uploadpack.allowfilter 1 &&
+ git clone --filter=blob:none --no-local --no-checkout tmp evil &&
+ rm -rf tmp &&
+
+ git -C evil config remote.origin.uploadpack \"\$TRASH_DIRECTORY/fake-upload-pack\" &&
+ write_script fake-upload-pack <<-\EOF &&
+ echo >&2 "fake-upload-pack running"
+ >"$TRASH_DIRECTORY/script-executed"
+ exit 1
+ EOF
+ export TRASH_DIRECTORY &&
+
+ # empty shallow file disables local clone optimization
+ >evil/.git/shallow
+'
+
+test_expect_success 'local clone must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git clone \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ evil clone1 2>err &&
+ grep "detected dubious ownership" err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'clone from file://... must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git clone \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ "file://$(pwd)/evil" clone2 2>err &&
+ grep "detected dubious ownership" err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'fetch from file://... must not fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ test_must_fail git fetch \
+ --upload-pack="GIT_TEST_ASSUME_DIFFERENT_OWNER=true git-upload-pack" \
+ "file://$(pwd)/evil" 2>err &&
+ grep "detected dubious ownership" err &&
+ ! grep "fake-upload-pack running" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'pack-objects should fetch from promisor remote and execute script' '
+ rm -f script-executed &&
+ echo "HEAD" | test_must_fail git -C evil pack-objects --revs --stdout >/dev/null 2>err &&
+ grep "fake-upload-pack running" err &&
+ test_path_is_file script-executed
+'
+
+test_expect_success 'clone from promisor remote does not lazy-fetch by default' '
+ rm -f script-executed &&
+ test_must_fail git clone evil no-lazy 2>err &&
+ grep "lazy fetching disabled" err &&
+ test_path_is_missing script-executed
+'
+
+test_expect_success 'promisor lazy-fetching can be re-enabled' '
+ rm -f script-executed &&
+ test_must_fail env GIT_NO_LAZY_FETCH=0 \
+ git clone evil lazy-ok 2>err &&
+ grep "fake-upload-pack running" err &&
+ test_path_is_file script-executed
+'
+
+test_done
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index f094e3d7f3..63c24f7f7c 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -1179,4 +1179,52 @@ test_expect_success 'submodule update --recursive skip submodules with strategy=
test_cmp expect.err actual.err
'
+test_expect_success CASE_INSENSITIVE_FS,SYMLINKS \
+ 'submodule paths must not follow symlinks' '
+
+ # This is only needed because we want to run this in a self-contained
+ # test without having to spin up an HTTP server; However, it would not
+ # be needed in a real-world scenario where the submodule is simply
+ # hosted on a public site.
+ test_config_global protocol.file.allow always &&
+
+ # Make sure that Git tries to use symlinks on Windows
+ test_config_global core.symlinks true &&
+
+ tell_tale_path="$PWD/tell.tale" &&
+ git init hook &&
+ (
+ cd hook &&
+ mkdir -p y/hooks &&
+ write_script y/hooks/post-checkout <<-EOF &&
+ echo HOOK-RUN >&2
+ echo hook-run >"$tell_tale_path"
+ EOF
+ git add y/hooks/post-checkout &&
+ test_tick &&
+ git commit -m post-checkout
+ ) &&
+
+ hook_repo_path="$(pwd)/hook" &&
+ git init captain &&
+ (
+ cd captain &&
+ git submodule add --name x/y "$hook_repo_path" A/modules/x &&
+ test_tick &&
+ git commit -m add-submodule &&
+
+ printf .git >dotgit.txt &&
+ git hash-object -w --stdin <dotgit.txt >dot-git.hash &&
+ printf "120000 %s 0\ta\n" "$(cat dot-git.hash)" >index.info &&
+ git update-index --index-info <index.info &&
+ test_tick &&
+ git commit -m add-symlink
+ ) &&
+
+ test_path_is_missing "$tell_tale_path" &&
+ test_must_fail git clone --recursive captain hooked 2>err &&
+ grep "directory not empty" err &&
+ test_path_is_missing "$tell_tale_path"
+'
+
test_done
diff --git a/t/t7423-submodule-symlinks.sh b/t/t7423-submodule-symlinks.sh
new file mode 100755
index 0000000000..3d3c7af3ce
--- /dev/null
+++ b/t/t7423-submodule-symlinks.sh
@@ -0,0 +1,67 @@
+#!/bin/sh
+
+test_description='check that submodule operations do not follow symlinks'
+
+. ./test-lib.sh
+
+test_expect_success 'prepare' '
+ git config --global protocol.file.allow always &&
+ test_commit initial &&
+ git init upstream &&
+ test_commit -C upstream upstream submodule_file &&
+ git submodule add ./upstream a/sm &&
+ test_tick &&
+ git commit -m submodule
+'
+
+test_expect_success SYMLINKS 'git submodule update must not create submodule behind symlink' '
+ rm -rf a b &&
+ mkdir b &&
+ ln -s b a &&
+ test_path_is_missing b/sm &&
+ test_must_fail git submodule update &&
+ test_path_is_missing b/sm
+'
+
+test_expect_success SYMLINKS,CASE_INSENSITIVE_FS 'git submodule update must not create submodule behind symlink on case insensitive fs' '
+ rm -rf a b &&
+ mkdir b &&
+ ln -s b A &&
+ test_must_fail git submodule update &&
+ test_path_is_missing b/sm
+'
+
+prepare_symlink_to_repo() {
+ rm -rf a &&
+ mkdir a &&
+ git init a/target &&
+ git -C a/target fetch ../../upstream &&
+ ln -s target a/sm
+}
+
+test_expect_success SYMLINKS 'git restore --recurse-submodules must not be confused by a symlink' '
+ prepare_symlink_to_repo &&
+ test_must_fail git restore --recurse-submodules a/sm &&
+ test_path_is_missing a/sm/submodule_file &&
+ test_path_is_dir a/target/.git &&
+ test_path_is_missing a/target/submodule_file
+'
+
+test_expect_success SYMLINKS 'git restore --recurse-submodules must not migrate git dir of symlinked repo' '
+ prepare_symlink_to_repo &&
+ rm -rf .git/modules &&
+ test_must_fail git restore --recurse-submodules a/sm &&
+ test_path_is_dir a/target/.git &&
+ test_path_is_missing .git/modules/a/sm &&
+ test_path_is_missing a/target/submodule_file
+'
+
+test_expect_success SYMLINKS 'git checkout -f --recurse-submodules must not migrate git dir of symlinked repo when removing submodule' '
+ prepare_symlink_to_repo &&
+ rm -rf .git/modules &&
+ test_must_fail git checkout -f --recurse-submodules initial &&
+ test_path_is_dir a/target/.git &&
+ test_path_is_missing .git/modules/a/sm
+'
+
+test_done
diff --git a/t/t7450-bad-git-dotfiles.sh b/t/t7450-bad-git-dotfiles.sh
index ba1f569bcb..8f94129e74 100755
--- a/t/t7450-bad-git-dotfiles.sh
+++ b/t/t7450-bad-git-dotfiles.sh
@@ -292,7 +292,7 @@ test_expect_success WINDOWS 'prevent git~1 squatting on Windows' '
fi
'
-test_expect_success 'git dirs of sibling submodules must not be nested' '
+test_expect_success 'setup submodules with nested git dirs' '
git init nested &&
test_commit -C nested nested &&
(
@@ -310,9 +310,39 @@ test_expect_success 'git dirs of sibling submodules must not be nested' '
git add .gitmodules thing1 thing2 &&
test_tick &&
git commit -m nested
- ) &&
+ )
+'
+
+test_expect_success 'git dirs of sibling submodules must not be nested' '
test_must_fail git clone --recurse-submodules nested clone 2>err &&
test_i18ngrep "is inside git dir" err
'
+test_expect_success 'submodule git dir nesting detection must work with parallel cloning' '
+ test_must_fail git clone --recurse-submodules --jobs=2 nested clone_parallel 2>err &&
+ cat err &&
+ grep -E "(already exists|is inside git dir|not a git repository)" err &&
+ {
+ test_path_is_missing .git/modules/hippo/HEAD ||
+ test_path_is_missing .git/modules/hippo/hooks/HEAD
+ }
+'
+
+test_expect_success 'checkout -f --recurse-submodules must not use a nested gitdir' '
+ git clone nested nested_checkout &&
+ (
+ cd nested_checkout &&
+ git submodule init &&
+ git submodule update thing1 &&
+ mkdir -p .git/modules/hippo/hooks/refs &&
+ mkdir -p .git/modules/hippo/hooks/objects/info &&
+ echo "../../../../objects" >.git/modules/hippo/hooks/objects/info/alternates &&
+ echo "ref: refs/heads/master" >.git/modules/hippo/hooks/HEAD
+ ) &&
+ test_must_fail git -C nested_checkout checkout -f --recurse-submodules HEAD 2>err &&
+ cat err &&
+ grep "is inside git dir" err &&
+ test_path_is_missing nested_checkout/thing2/.git
+'
+
test_done