Re: [PATCH] autofs: fix null deref in autofs_fill_super

From: Al Viro
Date: Tue Nov 14 2023 - 10:26:17 EST


On Tue, Nov 14, 2023 at 04:30:25PM +0800, Ian Kent wrote:

> I'll prepare a patch, the main thing that I was concerned about was
>
> whether the cause really was NULL root_inode but Edward more or less
>
> tested that.

One thing: that was a massaged copy of the variant in my local tree, so
this

> > managed_dentry_set_managed(s->s_root);

might be worth an explanation; mainline has __managed_dentry_set_managed()
here, and yes, it is safe since nothing can access it yet, but... it's
not worth skipping on spin_lock/spin_unlock for ->d_flags update here.