Re: [PATCH v7 04/19] xfs: Check for -ENOATTR or -EEXIST

Allison Collins
2020-02-24T21:18:46Z

On 2/24/20 6:08 AM, Brian Foster wrote:
> On Sat, Feb 22, 2020 at 07:05:56PM -0700, Allison Collins wrote:
>> Delayed operations cannot return error codes. So we must check for these conditions
>> first before starting set or remove operations
>>
>> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
>> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>> ---
>> fs/xfs/libxfs/xfs_attr.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
>> index 2255060..a2f812f 100644
>> --- a/fs/xfs/libxfs/xfs_attr.c
>> +++ b/fs/xfs/libxfs/xfs_attr.c
>> @@ -437,6 +437,14 @@ xfs_attr_set(
>> goto out_trans_cancel;
>>
>> xfs_trans_ijoin(args.trans, dp, 0);
>> +
>> + error = xfs_has_attr(&args);
>> + if (error == -EEXIST && (name->type & ATTR_CREATE))
>> + goto out_trans_cancel;
>> +
>> + if (error == -ENOATTR && (name->type & ATTR_REPLACE))
>> + goto out_trans_cancel;
>> +
>
> So xfs_has_attr() calls the format-specific variant for the attr fork.
> If it's node format, xfs_attr_node_hasname() allocs a state and only
> frees it if the lookup happens to fail. That looks like a potential
> memory leak... Perhaps that helper should free the state in any case the
> caller doesn't ask for a pointer?
>
> Brian
Ok, I see it. Will fix. Thanks!

Allison

>
>> error = xfs_attr_set_args(&args);
>> if (error)
>> goto out_trans_cancel;
>> @@ -525,6 +533,10 @@ xfs_attr_remove(
>> */
>> xfs_trans_ijoin(args.trans, dp, 0);
>>
>> + error = xfs_has_attr(&args);
>> + if (error != -EEXIST)
>> + goto out;
>> +
>> error = xfs_attr_remove_args(&args);
>> if (error)
>> goto out;
>> --
>> 2.7.4
>>
>