Re: [PATCH 1/5] 9pfs: fix qemu_mknodat(S_IFREG) on macOS

[Greg Kurz]

On Wed, 20 Apr 2022 11:03:52 +0900
Akihiko Odaki <akihiko.odaki@gmail.com> wrote:

> On 2022/04/19 20:40, Christian Schoenebeck wrote:
> > mknod() on macOS does not support creating regular files, so
> > divert to openat_file() if S_IFREG is passed with mode argument.
> > 
> > Furthermore, 'man 2 mknodat' on Linux says: "Zero file type is
> > equivalent to type S_IFREG".
> > 
> > Link: https://lore.kernel.org/qemu-devel/17933734.zYzKuhC07K@silver/
> > Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
> > ---
> >   hw/9pfs/9p-util-darwin.c | 4 ++++
> >   1 file changed, 4 insertions(+)
> > 
> > diff --git a/hw/9pfs/9p-util-darwin.c b/hw/9pfs/9p-util-darwin.c
> > index bec0253474..53e0625501 100644
> > --- a/hw/9pfs/9p-util-darwin.c
> > +++ b/hw/9pfs/9p-util-darwin.c
> > @@ -77,6 +77,10 @@ int fsetxattrat_nofollow(int dirfd, const char 
> > *filename, const char *name,
> >   int qemu_mknodat(int dirfd, const char *filename, mode_t mode, dev_t dev)
> >   {
> >       int preserved_errno, err;
> > +
> > +    if (S_ISREG(mode) || !(mode & S_IFMT)) {
> > +        return openat_file(dirfd, filename, O_CREAT, mode);
> > +    }
> >       if (!pthread_fchdir_np) {
> >           error_report_once("pthread_fchdir_np() not available on this 
> > version of macOS");
> >           return -ENOTSUP;
> 
> openat_file returns a file descriptor on success while mknodat returns 0 
> on success. The inconsistency should be handled.
> 

And most importantly that file descriptor must be closed !

> Regards,
> Akihiko Odaki