Re: [PATCH v2 2/5] 9pfs: fix qemu_mknodat(S_IFSOCK) on macOS

[Christian Schoenebeck]

On Donnerstag, 21. April 2022 18:36:31 CEST Greg Kurz wrote:
> On Thu, 21 Apr 2022 17:07:43 +0200
> 
> Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:
> > mknod() on macOS does not support creating sockets, so divert to
> > call sequence socket(), bind() and chmod() respectively if S_IFSOCK
> > was passed with mode argument.
> > 
> > Link: https://lore.kernel.org/qemu-devel/17933734.zYzKuhC07K@silver/
> > Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
> > Reviewed-by: Will Cohen <wwcohen@gmail.com>
> > ---
> > 
> >  hw/9pfs/9p-util-darwin.c | 27 ++++++++++++++++++++++++++-
> >  1 file changed, 26 insertions(+), 1 deletion(-)
> > 
> > diff --git a/hw/9pfs/9p-util-darwin.c b/hw/9pfs/9p-util-darwin.c
> > index e24d09763a..39308f2a45 100644
> > --- a/hw/9pfs/9p-util-darwin.c
> > +++ b/hw/9pfs/9p-util-darwin.c
> > @@ -74,6 +74,27 @@ int fsetxattrat_nofollow(int dirfd, const char
> > *filename, const char *name,> 
> >   */
> >  
> >  #if defined CONFIG_PTHREAD_FCHDIR_NP
> > 
> > +static int create_socket_file_at_cwd(const char *filename, mode_t mode) {
> > +    int fd, err;
> > +    struct sockaddr_un addr = {
> > +        .sun_family = AF_UNIX
> > +    };
> > +
> > +    fd = socket(PF_UNIX, SOCK_DGRAM, 0);
> > +    if (fd == -1) {
> > +        return fd;
> > +    }
> > +    snprintf(addr.sun_path, sizeof(addr.sun_path), "./%s", filename);
> > +    err = bind(fd, (struct sockaddr *) &addr, sizeof(addr));
> > +    if (err == -1) {
> > +        goto out;
> > +    }
> > +    err = chmod(addr.sun_path, mode);
> > +out:
> > +    close(fd);
> 
> You need close_preserve_errno() here.
> 
> Rest LGTM, so with that fixed, you can add:
> 
> Reviewed-by: Greg Kurz <groug@kaod.org>

Right, unlike patch 1, we might come from an error path here when closing.

I'll just s/close/close_preserve_errno/ this on my end before queuing, without 
sending a v3, unless somebody finds something else in this series.

Thanks!

Best regards,
Christian Schoenebeck