diff --git a/sequencer.c b/sequencer.c
index df11136f9d..2b66b85373 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -651,6 +651,7 @@ static int write_author_script(const char *message)
 			strbuf_addch(&buf, *(message++));
 		else
 			strbuf_addf(&buf, "'\\\\%c'", *(message++));
+	strbuf_addch(&buf, '\'');
 	res = write_message(buf.buf, buf.len, rebase_path_author_script(), 1);
 	strbuf_release(&buf);
 	return res;
@@ -721,7 +722,11 @@ static const char *read_author_ident(struct strbuf *buf)
 
 		eol = strchrnul(in, '\n');
 		*eol = '\0';
-		sq_dequote(in);
+		if (!sq_dequote(in)) {
+			warning(_("bad quoting on %s value in '%s'"),
+				keys[i], rebase_path_author_script());
+			return NULL;
+		}
 		len = strlen(in);
 
 		if (i > 0) /* separate values by spaces */
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 347a09502e..092139096e 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1384,7 +1384,7 @@ test_expect_success 'valid author header after --root swap' '
 	set_fake_editor &&
 	FAKE_LINES="2 1" git rebase -i --root &&
 	git cat-file commit HEAD^ >out &&
-	grep "^author ..*> @[0-9][0-9]* [-+][0-9][0-9]*$" out
+	grep "^author ..*> @[0-9][0-9]* [-+][0-9][0-9][0-9][0-9]$" out
 '
 
 test_done