[PATCH 1/2] mmc: Avoid null pointer dereference

[PATCH 1/2] mmc: Avoid null pointer dereference

[Philippe De Swert]

After the null check on md the code jumped to cmd_done, which then
will dereference md in mmc_blk_put. This patch avoids the possible
null pointer dereference in that case.

Signed-off-by: Philippe De Swert <philippedeswert@gmail.com>
---
 drivers/mmc/card/block.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index b180965..4bed186 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -384,7 +384,7 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
 	md = mmc_blk_get(bdev->bd_disk);
 	if (!md) {
 		err = -EINVAL;
-		goto cmd_done;
+		goto cmd_err;
 	}
 
 	card = md->queue.card;
@@ -483,6 +483,7 @@ cmd_rel_host:
 
 cmd_done:
 	mmc_blk_put(md);
+cmd_err:
 	kfree(idata->buf);
 	kfree(idata);
 	return err;
-- 
1.7.9.5

Re: [PATCH 1/2] mmc: Avoid null pointer dereference

[Namjae Jeon]

2012/4/12 Philippe De Swert <philippedeswert@gmail.com>:
> After the null check on md the code jumped to cmd_done, which then
> will dereference md in mmc_blk_put. This patch avoids the possible
> null pointer dereference in that case.
>
> Signed-off-by: Philippe De Swert <philippedeswert@gmail.com>
This patch is good also.
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>

Re: [PATCH 1/2] mmc: Avoid null pointer dereference

[Namjae Jeon]

Hi. Chris.

Would you check this patch ?

Thanks.

2012/4/12, Namjae Jeon <linkinjeon@gmail.com>:
> 2012/4/12 Philippe De Swert <philippedeswert@gmail.com>:
>> After the null check on md the code jumped to cmd_done, which then
>> will dereference md in mmc_blk_put. This patch avoids the possible
>> null pointer dereference in that case.
>>
>> Signed-off-by: Philippe De Swert <philippedeswert@gmail.com>
> This patch is good also.
> Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
>

Re: [PATCH 1/2] mmc: Avoid null pointer dereference

[Chris Ball]

Hi,

On Wed, May 09 2012, Namjae Jeon wrote:
> Hi. Chris.
>
> Would you check this patch ?
>
> Thanks.
>
> 2012/4/12, Namjae Jeon <linkinjeon@gmail.com>:
>> 2012/4/12 Philippe De Swert <philippedeswert@gmail.com>:
>>> After the null check on md the code jumped to cmd_done, which then
>>> will dereference md in mmc_blk_put. This patch avoids the possible
>>> null pointer dereference in that case.
>>>
>>> Signed-off-by: Philippe De Swert <philippedeswert@gmail.com>
>> This patch is good also.
>> Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>

Thanks for the reminder -- pushed to mmc-next for 3.5.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child