[PATCH liburing 1/4] add a test for bad buf_ring register

[Dylan Yudaken <dylany@fb.com>]

This shows up a kernel panic in v5.19-rc7

Signed-off-by: Dylan Yudaken <dylany@fb.com>
---
 test/buf-ring.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/buf-ring.c b/test/buf-ring.c
index 5e032663d93b..b17030cbe952 100644
--- a/test/buf-ring.c
+++ b/test/buf-ring.c
@@ -206,6 +206,30 @@ static int test_reg_unreg(int bgid)
 	return 0;
 }
 
+static int test_bad_reg(int bgid)
+{
+	struct io_uring ring;
+	int ret;
+	struct io_uring_buf_reg reg = { };
+
+	ret = t_create_ring(1, &ring, 0);
+	if (ret == T_SETUP_SKIP)
+		return 0;
+	else if (ret != T_SETUP_OK)
+		return 1;
+
+	reg.ring_addr = 4096;
+	reg.ring_entries = 32;
+	reg.bgid = bgid;
+
+	ret = io_uring_register_buf_ring(&ring, &reg, 0);
+	if (!ret)
+		fprintf(stderr, "Buffer ring register worked unexpectedly\n");
+
+	io_uring_queue_exit(&ring);
+	return !ret;
+}
+
 static int test_one_read(int fd, int bgid, struct io_uring *ring)
 {
 	int ret;
@@ -359,6 +383,12 @@ int main(int argc, char *argv[])
 		if (no_buf_ring)
 			break;
 
+		ret = test_bad_reg(bgids[i]);
+		if (ret) {
+			fprintf(stderr, "test_bad_reg failed\n");
+			return T_EXIT_FAIL;
+		}
+
 		ret = test_double_reg_unreg(bgids[i]);
 		if (ret) {
 			fprintf(stderr, "test_double_reg_unreg failed\n");
-- 
2.30.2