Re: [PATCH 0/5] Fix AT_EMPTY_PATH handling

[Corinna Vinschen <corinna-cygwin@cygwin.com>]

Johannes? Ping?

On Jul 12 14:07, Corinna Vinschen wrote:
> From: Corinna Vinschen <corinna@vinschen.de>
> 
> The GLIBC extension AT_EMPTY_PATH allows the functions fchownat
> and fstatat to operate on dirfd alone, if the given pathname is an
> empty string.  This also allows to operate on any file type, not
> only directories.
> 
> Commit fa84aa4dd2fb4 broke this.  It only allows dirfd to be a
> directory in calls to these two functions.
> 
> Fix that by handling AT_EMPTY_PATH right in gen_full_path_at.
> A valid dirfd and an empty pathname is now a valid combination
> and, noticably, this returns a valid path in path_ret.  That
> in turn allows to remove the additional path generation code
> from the callers.
> 
> Fixes: fa84aa4dd2fb ("Cygwin: fix errno values set by readlinkat")
> Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
> 
> Corinna Vinschen (5):
>   Cygwin: gen_full_path_at: drop never reached code
>   Define _AT_NULL_PATHNAME_ALLOWED
>   Cygwin: use new _AT_NULL_PATHNAME_ALLOWED flag
>   Cygwin: Fix and streamline AT_EMPTY_PATH handling
>   Cygwin: add AT_EMPTY_PATH fix to release message
> 
>  newlib/libc/include/sys/_default_fcntl.h | 11 +++--
>  winsup/cygwin/release/3.4.8              |  4 ++
>  winsup/cygwin/syscalls.cc                | 61 ++++++------------------
>  3 files changed, 25 insertions(+), 51 deletions(-)
> 
> -- 
> 2.40.1