null_blk: fix ida error handling in null_add_dev()

[ Upstream commit ee452a8d984f94fa8e894f003a52e776e4572881 ]

There needs to be some error checking if ida_simple_get() fails.
Also call ida_free() if there are errors later.

Fixes: 94bc02e30fb8 ("nullb: use ida to manage index")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YtEhXsr6vJeoiYhd@kili
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 187d779..4c8b410 100644 (file)
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1884,8 +1884,13 @@ static int null_add_dev(struct nullb_device *dev)
        blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, nullb->q);
 
        mutex_lock(&lock);
-       nullb->index = ida_simple_get(&nullb_indexes, 0, 0, GFP_KERNEL);
-       dev->index = nullb->index;
+       rv = ida_simple_get(&nullb_indexes, 0, 0, GFP_KERNEL);
+       if (rv < 0) {
+               mutex_unlock(&lock);
+               goto out_cleanup_zone;
+       }
+       nullb->index = rv;
+       dev->index = rv;
        mutex_unlock(&lock);
 
        blk_queue_logical_block_size(nullb->q, dev->blocksize);
@@ -1905,13 +1910,16 @@ static int null_add_dev(struct nullb_device *dev)
 
        rv = null_gendisk_register(nullb);
        if (rv)
-               goto out_cleanup_zone;
+               goto out_ida_free;
 
        mutex_lock(&lock);
        list_add_tail(&nullb->list, &nullb_list);
        mutex_unlock(&lock);
 
        return 0;
+
+out_ida_free:
+       ida_free(&nullb_indexes, nullb->index);
 out_cleanup_zone:
        null_free_zoned_dev(dev);
 out_cleanup_disk: