grep: take the read-lock when adding a submodule

diff --git a/builtin/grep.c b/builtin/grep.c
index cd0e51f3c04b1e6fc297a8806fa663d86ebc7734..6946cf4bbc825cbd1335ab5464428f54483701f8 100644 (file)
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -431,7 +431,9 @@ static int grep_submodule(struct grep_opt *opt, struct repository *superproject,
         * store is no longer global and instead is a member of the repository
         * object.
         */
+       grep_read_lock();
        add_to_alternates_memory(submodule.objectdir);
+       grep_read_unlock();
 
        if (oid) {
                struct object *object;