[PATCH] mount.cifs: ignore x-* mount options

[PATCH] mount.cifs: ignore x-* mount options

[Karel Zak]

x-* prefix is used for userspace mount options and it's pretty
commonly used to extend fstab configuration in systemd world (e.g.
x-systemd.automount). These options is necessary to ignored.

The command mount(8) does not pass x-* mount options to mount.<type>
helpers, but in some use-cases it's possible that the cifs helper reads
mount options from fstab or users directly call mount.cifs and copy & past
mount options, etc.

This patch marks all options prefixed by "x-" as OPT_IGNORE to make
things more robust for end-users. We already uses the same concept for
_netdev.

Signed-off-by: Karel Zak <kzak-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 mount.cifs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mount.cifs.c b/mount.cifs.c
index 3535096..5c5734f 100644
--- a/mount.cifs.c
+++ b/mount.cifs.c
@@ -756,6 +756,8 @@ static int parse_opt_token(const char *token)
 		return OPT_BKUPGID;
 	if (strncmp(token, "nofail", 6) == 0)
 		return OPT_NOFAIL;
+	if (strncmp(token, "x-", 2) == 0)
+		return OPT_IGNORE;
 
 	return OPT_ERROR;
 }
-- 
2.4.3

Re: [PATCH] mount.cifs: ignore x-* mount options

[Jeff Layton]

On Thu,  7 Jan 2016 11:02:49 +0100
Karel Zak <kzak-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:

> x-* prefix is used for userspace mount options and it's pretty
> commonly used to extend fstab configuration in systemd world (e.g.
> x-systemd.automount). These options is necessary to ignored.
> 
> The command mount(8) does not pass x-* mount options to mount.<type>
> helpers, but in some use-cases it's possible that the cifs helper reads
> mount options from fstab or users directly call mount.cifs and copy & past
> mount options, etc.
> 
> This patch marks all options prefixed by "x-" as OPT_IGNORE to make
> things more robust for end-users. We already uses the same concept for
> _netdev.
> 
> Signed-off-by: Karel Zak <kzak-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  mount.cifs.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/mount.cifs.c b/mount.cifs.c
> index 3535096..5c5734f 100644
> --- a/mount.cifs.c
> +++ b/mount.cifs.c
> @@ -756,6 +756,8 @@ static int parse_opt_token(const char *token)
>  		return OPT_BKUPGID;
>  	if (strncmp(token, "nofail", 6) == 0)
>  		return OPT_NOFAIL;
> +	if (strncmp(token, "x-", 2) == 0)
> +		return OPT_IGNORE;
>  
>  	return OPT_ERROR;
>  }

Thanks, looks reasonable -- merged. I'll plan to cut a new cifs-utils
release in the next few weeks. There haven't been many patches over the
last year or so, but it has been quite a while since the last one.

-- 
Jeff Layton <jlayton-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org>