On 2022/4/21 19:25, Nikolay Borisov wrote:
>
>
> On 21.04.22 г. 14:21 ч., Nikolay Borisov wrote:
>>
>>
>> On 21.04.22 г. 12:51 ч., Haowen Bai wrote:
>>> Free "bargs" before return.
>>>
>>> Signed-off-by: Haowen Bai <[email protected]>
>>> ---
>>> 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:
>>
>
>
> Actually to simplify further:
>
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 7a6974e877f4..bbda55d41a06 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -4353,6 +4353,7 @@ static long btrfs_ioctl_balance(struct file *file,
> void __user *arg)
> bargs = memdup_user(arg, sizeof(*bargs));
> if (IS_ERR(bargs)) {
> ret = PTR_ERR(bargs);
> + bargs = NULL;
> goto out;
> }
>
> @@ -4391,13 +4392,11 @@ 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;
> }
> } else {
> /* this is (1) */
> - mutex_unlock(&fs_info->balance_mutex);
> ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
> goto out;
> }
> @@ -4406,7 +4405,7 @@ static long btrfs_ioctl_balance(struct file *file,
> void __user *arg)
> if (bargs->flags & BTRFS_BALANCE_RESUME) {
> if (!fs_info->balance_ctl) {
> ret = -ENOTCONN;
> - goto out_bargs;
> + goto out;
> }
>
> bctl = fs_info->balance_ctl;
> @@ -4420,18 +4419,18 @@ static long btrfs_ioctl_balance(struct file
> *file, void __user *arg)
>
> if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK |
> BTRFS_BALANCE_TYPE_MASK)) {
> ret = -EINVAL;
> - goto out_bargs;
> + goto out;
> }
>
> if (fs_info->balance_ctl) {
> ret = -EINPROGRESS;
> - goto out_bargs;
> + goto out;
> }
>
> bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
> if (!bctl) {
> ret = -ENOMEM;
> - goto out_bargs;
> + goto out;
> }
>
> memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
> @@ -4457,12 +4456,11 @@ static long btrfs_ioctl_balance(struct file
> *file, void __user *arg)
> }
>
> kfree(bctl);
> -out_bargs:
This looks much better, without the extra label it's easier to read.
But, the @need_unlock variable seems to be uninitialized now, as it's
only set in case (3), but case (2) and (1) now goes through out which
needs to check @need_unlock.
Thanks,
Qu
> +out:
> kfree(bargs);
> mutex_unlock(&fs_info->balance_mutex);
> if (need_unlock)
> btrfs_exclop_finish(fs_info);
> -out:
> mnt_drop_write_file(file);
> return ret;
> }
>
>
>
>