[PATCH] fs: Check if automount actually mounts something

[Sascha Hauer]

On Thu, Jul 14, 2022 at 11:12:38PM +0200, Uwe Kleine-König wrote:
> On Thu, Jul 14, 2022 at 09:35:09PM +0200, Sascha Hauer wrote:
> > An automount command that returns successfully but doesn't mount
> > anything makes barebox hang as can be reproduced with:
> > 
> > automount -d /mnt/foo true
> > ls /mnt/foo
> > 
> > Check if the current dentry is a mountpoint after running the automount
> > command, otherwise return with an error from automount_mount().
> 
> While I think the intention of this patch is fine, I have little doubts
> if that breaks some workflows, e.g. something like:
> 
> 	automount -d /mnt/tralala 'for p in 0 1 2; do mkdir ${automount_path}/${p} && mount /dev/disk0.${p} ${automount_path}/${p} || break; done'

You would create 3 automountpoints for that.

> 
> I admit it's a bit constructed, but maybe that's only because I'm not
> creative enough?

Yes, it is constructed ;)

I can't think of a better example, but I'm not sure we should support
such cases.

Sascha


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