[PATCH] md: Fix an unlock in an error path of lbs_store()

[PATCH] md: Fix an unlock in an error path of lbs_store()

[Bart Van Assche]

If mddev_lock() fails, lbs_store() calls mddev_unlock() although the
reconfig_mutex is not held. Fix this by returning the mddev_lock() error
code directly. This bug has been detected by the Clang thread-safety
analyzer.

Fixes: 62ed1b582246 ("md: allow configuring logical block size")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/md/md.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index ac03b99f6428..7ce527073be9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6049,11 +6049,10 @@ lbs_store(struct mddev *mddev, const char *buf, size_t len)
 
 	err = mddev_lock(mddev);
 	if (err)
-		goto unlock;
+		return err;
 
 	err = mddev_set_logical_block_size(mddev, lbs);
 
-unlock:
 	mddev_unlock(mddev);
 	return err ?: len;
 }

Re: [PATCH] md: Fix an unlock in an error path of lbs_store()

[yu kuai]

Hi,

在 2026/10/27 3:57, Bart Van Assche 写道:
> If mddev_lock() fails, lbs_store() calls mddev_unlock() although the
> reconfig_mutex is not held. Fix this by returning the mddev_lock() error
> code directly. This bug has been detected by the Clang thread-safety
> analyzer.
>
> Fixes: 62ed1b582246 ("md: allow configuring logical block size")
> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
> ---
>   drivers/md/md.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)

This problem is already fixed:

[PATCH] md: fix mddev_unlock() called without holding lock in 
lbs_store() - Jack Wang <https://lore.kernel.org/all/20260920103705.23191-1-jinpu.wang@ionos.com/>

>
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index ac03b99f6428..7ce527073be9 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -6049,11 +6049,10 @@ lbs_store(struct mddev *mddev, const char *buf, size_t len)
>   
>   	err = mddev_lock(mddev);
>   	if (err)
> -		goto unlock;
> +		return err;
>   
>   	err = mddev_set_logical_block_size(mddev, lbs);
>   
> -unlock:
>   	mddev_unlock(mddev);
>   	return err ?: len;
>   }

-- 
Thanks,
Kuai