In pcd_init_units, if blk_mq_init_sq_queue fails, need to set queue to
NULL before put_disk, otherwise null-ptr-deref Read will occur.

put_disk
  kobject_put
    disk_release
      blk_put_queue(disk->queue)

Fixes: f0d176255401 ("paride/pcd: Fix potential NULL pointer dereference and 
mem leak")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: zhengbin <[email protected]>
---
 drivers/block/paride/pcd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index 001dbdc..bfca80d 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -314,8 +314,8 @@ static void pcd_init_units(void)
                disk->queue = blk_mq_init_sq_queue(&cd->tag_set, &pcd_mq_ops,
                                                   1, BLK_MQ_F_SHOULD_MERGE);
                if (IS_ERR(disk->queue)) {
-                       put_disk(disk);
                        disk->queue = NULL;
+                       put_disk(disk);
                        continue;
                }

--
2.7.4

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