[libvirt] [PATCH] qemu: fix up permissions for pre-created UNIX sockets

[Jiri Denemark]

On Wed, Oct 03, 2018 at 14:44:28 +0200, Ján Tomko wrote:
> My commit d6b8838 fixed the uid:gid for the pre-created UNIX sockets
> but did not account for the different umask of libvirtd and QEMU.
> Since commit 0e1a1a8c we set umask to '0002' for the QEMU process.
> Manually tune-up the permissions to match what we would have gotten
> if QEMU had created the socket.
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1633389
> 
> Signed-off-by: Ján Tomko <jtomko at redhat.com>
> ---
>  src/qemu/qemu_command.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 887947dc11..d77cf8c2d6 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -5034,6 +5034,12 @@ qemuOpenChrChardevUNIXSocket(const virDomainChrSourceDef *dev)
>          goto error;
>      }
>  
> +    /* We run QEMU with umask 0002. Compensate for the umask
> +     * libvirtd might be running under to get the same permission
> +     * QEMU would have. */
> +    if (virFileUpdatePerm(dev->data.nix.path, 0002, 0664) < 0)
> +        goto error;
> +

The virFileUpdatePerm API is a very interesting one...

>      return fd;
>  
>   error:

Reviewed-by: Jiri Denemark <jdenemar at redhat.com>