diff --git a/t/lib-proto-disable.sh b/t/lib-proto-disable.sh
index 02f49cb409..83babe57d9 100644
--- a/t/lib-proto-disable.sh
+++ b/t/lib-proto-disable.sh
@@ -147,29 +147,33 @@ test_config () {
 	# Test clone/fetch/push with protocol.allow user defined default
 	test_expect_success "clone $desc (enabled)" '
 		rm -rf tmp.git &&
-		git config --global protocol.allow always &&
+		test_config_global protocol.allow always &&
 		git clone --bare "$url" tmp.git
 	'
 
 	test_expect_success "fetch $desc (enabled)" '
+		test_config_global protocol.allow always &&
 		git -C tmp.git fetch
 	'
 
 	test_expect_success "push $desc (enabled)" '
+		test_config_global protocol.allow always &&
 		git -C tmp.git push origin HEAD:pushed
 	'
 
 	test_expect_success "push $desc (disabled)" '
-		git config --global protocol.allow never &&
+		test_config_global protocol.allow never &&
 		test_must_fail git -C tmp.git push origin HEAD:pushed
 	'
 
 	test_expect_success "fetch $desc (disabled)" '
+		test_config_global protocol.allow never &&
 		test_must_fail git -C tmp.git fetch
 	'
 
 	test_expect_success "clone $desc (disabled)" '
 		rm -rf tmp.git &&
+		test_config_global protocol.allow never &&
 		test_must_fail git clone --bare "$url" tmp.git
 	'
 }