Messages in this thread | | | Subject | Re: [PATCH 31/34] vfs: syscall: Add fspick() to select a superblock for reconfiguration [ver #12] | From | Alan Jenkins <> | Date | Wed, 17 Oct 2018 15:31:26 +0100 |
| |
On 17/10/2018 14:20, David Howells wrote: > David Howells <dhowells@redhat.com> wrote: > >> I should probably check that the picked point is actually a mountpoint. > The root of the mount object at the path specified, that is, perhaps with > something like the attached. > > David
I agree. I'm happy to see this is using the same check as do_remount().
* change filesystem flags. dir should be a physical root of filesystem. * If you've mounted a non-root directory somewhere and want to do remount * on it - tough luck. */
Thanks
Alan
> --- > diff --git a/fs/fsopen.c b/fs/fsopen.c > index f673e93ac456..aaaaa17a233c 100644 > --- a/fs/fsopen.c > +++ b/fs/fsopen.c > @@ -186,6 +186,10 @@ SYSCALL_DEFINE3(fspick, int, dfd, const char __user *, path, unsigned int, flags > if (ret < 0) > goto err; > > + ret = -EINVAL; > + if (target.mnt->mnt_root != target.dentry) > + goto err_path; > + > fc = vfs_new_fs_context(target.dentry->d_sb->s_type, target.dentry, > 0, 0, FS_CONTEXT_FOR_RECONFIGURE); > if (IS_ERR(fc)) { >
| |