[PATCH 7/9] loop: don't allow deleting an unspecified loop device

[Christoph Hellwig <hch@xxxxxx>]

Passing a negative index to loop_lookup while return any unbound device.
Doing that for a delete does not make much sense, so add check to
explicitly reject that case.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 drivers/block/loop.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 01d393a60b37..58fc29f1b1ae 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2235,6 +2235,11 @@ static int loop_control_remove(int idx)
 {
 	struct loop_device *lo;
 	int ret;
+
+	if (idx < 0) {
+		pr_warn("deleting an unspecified loop device is not supported.\n");
+		return -EINVAL;
+	}
 		
 	ret = mutex_lock_killable(&loop_ctl_mutex);
 	if (ret)
-- 
2.30.2