[PATCH 0/3] Some O_PATH fixes

[Ken Brown]

On 1/28/2020 2:01 PM, Ken Brown wrote:
> On 1/28/2020 12:06 PM, Corinna Vinschen wrote:
>> On Jan 27 13:21, Ken Brown wrote:
>>> Ken Brown (3):
>>>     Cygwin: fhandler_base::fstat_fs: accomodate the O_PATH flag
>>>     Cygwin: fhandler_disk_file::fstatvfs: refactor
>>>     Cygwin: FIFO::fstatvfs: use our handle if O_PATH is set
>>>
>>>    winsup/cygwin/fhandler.h            |  1 +
>>>    winsup/cygwin/fhandler_disk_file.cc | 24 +++++++++++++++++-------
>>>    winsup/cygwin/fhandler_fifo.cc      |  8 ++++++++
>>>    3 files changed, 26 insertions(+), 7 deletions(-)
>>>
>>> -- 
>>> 2.21.0
>>
>> Patches are looking good to me.
> 
> OK, I'll push them.
> 
>> As outlined on IRC, I found a problem with the ACLs created on new
>> FIFOs and frixed that (I think).  However, Cygwin doesn't actually
>> return the real permissions in stat(), only the constant perms 0666,
>> kind of like for symlinks.  I didn't have time to look into that yet,
>> but it would be great if we could fix that, too.
> 
> I'll take a look if you don't get to it first.

Two quick thoughts, and then I won't have time to think about this any more 
until tomorrow:

First, I wonder why in fstat_fs we're not using the stat handle (i.e., pc.handle()).

Second, in the call to get_file_attribute in fstat_helper 
(fhandler_disk_file.cc:478), why do we set the first argument to NULL instead of 
using our handle?

In both cases I don't immediately see a connection with the permissions problem, 
but it seems inefficient and makes the code confusing.  I might well be missing 
something, however.

Ken