submodule: stop sanitizing config options

The point of having a whitelist of command-line config
options to pass to submodules was two-fold:

  1. It prevented obvious nonsense like using core.worktree
     for multiple repos.

  2. It could prevent surprise when the user did not mean
     for the options to leak to the submodules (e.g.,
     http.sslverify=false).

For case 1, the answer is mostly "if it hurts, don't do
that". For case 2, we can note that any such example has a
matching inverted surprise (e.g., a user who meant
http.sslverify=true to apply everywhere, but it didn't).

So this whitelist is probably not giving us any benefit, and
is already creating a hassle as people propose things to put
on it. Let's just drop it entirely.

Note that we still need to keep a special code path for
"prepare the submodule environment", because we still have
to take care to pass through $GIT_CONFIG_PARAMETERS (and
block the rest of the repo-specific environment variables).

We can do this easily from within the submodule shell
script, which lets us drop the submodule--helper option
entirely (and it's OK to do so because as a "--" program, it
is entirely a private implementation detail).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/submodule--helper.c

@@ -260,22 +260,6 @@ static int module_clone(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
-static int module_sanitize_config(int argc, const char **argv, const char *prefix)
-{
-	struct strbuf sanitized_config = STRBUF_INIT;
-
-	if (argc > 1)
-		usage(_("git submodule--helper sanitize-config"));
-
-	git_config_from_parameters(sanitize_submodule_config, &sanitized_config);
-	if (sanitized_config.len)
-		printf("%s\n", sanitized_config.buf);
-
-	strbuf_release(&sanitized_config);
-
-	return 0;
-}
-
 struct cmd_struct {
 	const char *cmd;
 	int (*fn)(int, const char **, const char *);
@@ -285,7 +269,6 @@ static struct cmd_struct commands[] = {
 	{"list", module_list},
 	{"name", module_name},
 	{"clone", module_clone},
-	{"sanitize-config", module_sanitize_config},
 };
 
 int cmd_submodule__helper(int argc, const char **argv, const char *prefix)

git-submodule.sh

@@ -197,9 +197,9 @@ isnumber()
 # of the settings from GIT_CONFIG_PARAMETERS.
 sanitize_submodule_env()
 {
-	sanitized_config=$(git submodule--helper sanitize-config)
+	save_config=$GIT_CONFIG_PARAMETERS
 	clear_local_git_env
-	GIT_CONFIG_PARAMETERS=$sanitized_config
+	GIT_CONFIG_PARAMETERS=$save_config
 	export GIT_CONFIG_PARAMETERS
 }
 

submodule.c

@@ -1098,50 +1098,13 @@ void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
 	strbuf_release(&rel_path);
 	free((void *)real_work_tree);
 }
-/*
- * Rules to sanitize configuration variables that are Ok to be passed into
- * submodule operations from the parent project using "-c". Should only
- * include keys which are both (a) safe and (b) necessary for proper
- * operation.
- */
-static int submodule_config_ok(const char *var)
-{
-	if (starts_with(var, "credential."))
-		return 1;
-	return 0;
-}
-
-int sanitize_submodule_config(const char *var, const char *value, void *data)
-{
-	struct strbuf *out = data;
-
-	if (submodule_config_ok(var)) {
-		if (out->len)
-			strbuf_addch(out, ' ');
-
-		if (value)
-			sq_quotef(out, "%s=%s", var, value);
-		else
-			sq_quote_buf(out, var);
-	}
-
-	return 0;
-}
 
 void prepare_submodule_repo_env(struct argv_array *out)
 {
 	const char * const *var;
 
 	for (var = local_repo_env; *var; var++) {
-		if (!strcmp(*var, CONFIG_DATA_ENVIRONMENT)) {
-			struct strbuf sanitized_config = STRBUF_INIT;
-			git_config_from_parameters(sanitize_submodule_config,
-						   &sanitized_config);
-			argv_array_pushf(out, "%s=%s", *var, sanitized_config.buf);
-			strbuf_release(&sanitized_config);
-		} else {
+		if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 			argv_array_push(out, *var);
-		}
 	}
-
 }

submodule.h

@@ -43,19 +43,10 @@ int find_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_nam
 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name);
 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir);
 
-/*
- * This function is intended as a callback for use with
- * git_config_from_parameters(). It ignores any config options which
- * are not suitable for passing along to a submodule, and accumulates the rest
- * in "data", which must be a pointer to a strbuf. The end result can
- * be put into $GIT_CONFIG_PARAMETERS for passing to a sub-process.
- */
-int sanitize_submodule_config(const char *var, const char *value, void *data);
-
 /*
  * Prepare the "env_array" parameter of a "struct child_process" for executing
  * a submodule by clearing any repo-specific envirionment variables, but
- * retaining any config approved by sanitize_submodule_config().
+ * retaining any config in the environment.
  */
 void prepare_submodule_repo_env(struct argv_array *out);
 

t/t7412-submodule--helper.sh

@@ -1,26 +0,0 @@
-#!/bin/sh
-#
-# Copyright (c) 2016 Jacob Keller
-#
-
-test_description='Basic plumbing support of submodule--helper
-
-This test verifies the submodule--helper plumbing command used to implement
-git-submodule.
-'
-
-. ./test-lib.sh
-
-test_expect_success 'sanitize-config clears configuration' '
-	git -c user.name="Some User" submodule--helper sanitize-config >actual &&
-	test_must_be_empty actual
-'
-
-sq="'"
-test_expect_success 'sanitize-config keeps credential.helper' '
-	git -c credential.helper=helper submodule--helper sanitize-config >actual &&
-	echo "${sq}credential.helper=helper${sq}" >expect &&
-	test_cmp expect actual
-'
-
-test_done