2013-04-12 18:27:27

by Asai Thambi SP

Subject: [PATCH 1/2] mtip32xx: fix a smatch warning

Reported smatch warning:
drivers/block/mtip32xx/mtip32xx.c:4163 mtip_block_shutdown() warn: variable dereferenced before check 'dd->disk' (see line 4159)

dd->disk->disk_name accessed before the check if dd->disk is NULL. Fixed this
and access of dd->queue/dd->disk->queue.

Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Asai Thambi S P <[email protected]>
---
drivers/block/mtip32xx/mtip32xx.c | 18 ++++++++----------
1 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 32c6780..d11ea92 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -4156,26 +4156,24 @@ static int mtip_block_remove(struct driver_data *dd)
*/
static int mtip_block_shutdown(struct driver_data *dd)
{
- dev_info(&dd->pdev->dev,
- "Shutting down %s ...\n", dd->disk->disk_name);
-
/* Delete our gendisk structure, and cleanup the blk queue. */
if (dd->disk) {
- if (dd->disk->queue)
+ dev_info(&dd->pdev->dev,
+ "Shutting down %s ...\n", dd->disk->disk_name);
+
+ if (dd->disk->queue) {
del_gendisk(dd->disk);
- else
+ blk_cleanup_queue(dd->queue);
+ } else
put_disk(dd->disk);
+ dd->disk = NULL;
+ dd->queue = NULL;
}

-
spin_lock(&rssd_index_lock);
ida_remove(&rssd_index_ida, dd->index);
spin_unlock(&rssd_index_lock);

- blk_cleanup_queue(dd->queue);
- dd->disk = NULL;
- dd->queue = NULL;
-
mtip_hw_shutdown(dd);
return 0;
}
--
1.7.1

2013-04-14 08:26:21

by Jens Axboe

Subject: Re: [PATCH 1/2] mtip32xx: fix a smatch warning

On Fri, Apr 12 2013, Asai Thambi S P wrote:
>
> Reported smatch warning:
> drivers/block/mtip32xx/mtip32xx.c:4163 mtip_block_shutdown() warn: variable dereferenced before check 'dd->disk' (see line 4159)
>
> dd->disk->disk_name accessed before the check if dd->disk is NULL. Fixed this
> and access of dd->queue/dd->disk->queue.

Applied for 3.10, thanks.

--
Jens Axboe