[PATCH] skd: error pointer dereference in skd_cons_disk()
STALE3330d
From: Dan Carpenter <hidden>
Date: 2017-08-23 11:21:06
Also in:
kernel-janitors
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
My initial impulse was to check for IS_ERR_OR_NULL() but when I looked
at this code a bit more closely, we should only need to check for
IS_ERR().
The blk_mq_alloc_tag_set() returns negative error codes and zero on
success so we can just do an "if (rc) goto err_out;". It's better to
preserve the error code anyhow. The blk_mq_init_queue() returns error
pointers on failure, it never returns NULL. We can also remove the
"q = NULL;" at the start because that's no longer needed.
Fixes: ca33dd92968b ("skd: Convert to blk-mq")
Signed-off-by: Dan Carpenter <redacted>
diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index 9b99081a623c..8579eef80ef1 100644
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c@@ -2862,7 +2862,6 @@ static int skd_cons_disk(struct skd_device *skdev) disk->fops = &skd_blockdev_ops; disk->private_data = skdev; - q = NULL; memset(&skdev->tag_set, 0, sizeof(skdev->tag_set)); skdev->tag_set.ops = &skd_mq_ops; skdev->tag_set.nr_hw_queues = 1;
@@ -2874,13 +2873,13 @@ static int skd_cons_disk(struct skd_device *skdev) BLK_MQ_F_SG_MERGE | BLK_ALLOC_POLICY_TO_MQ_FLAG(BLK_TAG_ALLOC_FIFO); skdev->tag_set.driver_data = skdev; - if (blk_mq_alloc_tag_set(&skdev->tag_set) >= 0) { - q = blk_mq_init_queue(&skdev->tag_set); - if (!q) - blk_mq_free_tag_set(&skdev->tag_set); - } - if (!q) { - rc = -ENOMEM; + rc = blk_mq_alloc_tag_set(&skdev->tag_set); + if (rc) + goto err_out; + q = blk_mq_init_queue(&skdev->tag_set); + if (IS_ERR(q)) { + blk_mq_free_tag_set(&skdev->tag_set); + rc = PTR_ERR(q); goto err_out; } blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);