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Message-ID: <2aeffa33-e591-acad-f96f-59cfadb5aeb2@suse.com>
Date:   Thu, 21 Apr 2022 14:21:41 +0300
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Subject: Re: [PATCH] btrfs: Fix a memory leak in btrfs_ioctl_balance()
Content-Language: en-US
To:     Haowen Bai <baihaowen@meizu.com>, Chris Mason <clm@fb.com>,
        Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>
Cc:     linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1650534677-31554-1-git-send-email-baihaowen@meizu.com>
From:   Nikolay Borisov <nborisov@suse.com>
In-Reply-To: <1650534677-31554-1-git-send-email-baihaowen@meizu.com>
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On 21.04.22 г. 12:51 ч., Haowen Bai wrote:
> Free "bargs" before return.
> 
> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> ---
>   fs/btrfs/ioctl.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index f08233c2b0b2..d4c8bea914b7 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -4389,13 +4389,13 @@ static long btrfs_ioctl_balance(struct file *file, void __user *arg)
>   			/* this is (2) */
>   			mutex_unlock(&fs_info->balance_mutex);
>   			ret = -EINPROGRESS;
> -			goto out;
> +			goto out_bargs;
>   		}
>   	} else {
>   		/* this is (1) */
>   		mutex_unlock(&fs_info->balance_mutex);
>   		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
> -		goto out;
> +		goto out_bargs;
>   	}
>   
>   locked:

I think this is a better fix:

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 7a6974e877f4..906ed1b93654 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4391,15 +4391,13 @@ static long btrfs_ioctl_balance(struct file 
*file, void __user *arg)
                         goto again;
                 } else {
                         /* this is (2) */
-                       mutex_unlock(&fs_info->balance_mutex);
                         ret = -EINPROGRESS;
-                       goto out;
+                       goto out_bargs;
                 }
         } else {
                 /* this is (1) */
-               mutex_unlock(&fs_info->balance_mutex);
                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
-               goto out;
+               goto out_bargs;
         }

  locked: