On Tue, Oct 22, 2019 at 11:46 PM Mark Salyzyn <salyzyn@xxxxxxxxxxx> wrote: > > Assumption never checked, should fail if the mounter creds are not > sufficient. > > Signed-off-by: Mark Salyzyn <salyzyn@xxxxxxxxxxx> > Cc: Miklos Szeredi <miklos@xxxxxxxxxx> > Cc: Jonathan Corbet <corbet@xxxxxxx> > Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> > Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> > Cc: Amir Goldstein <amir73il@xxxxxxxxx> > Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > Cc: Stephen Smalley <sds@xxxxxxxxxxxxx> > Cc: linux-unionfs@xxxxxxxxxxxxxxx > Cc: linux-doc@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: kernel-team@xxxxxxxxxxx > > --- > v11 + v12 +v13 + v14 - rebase > > v10: > - return NULL rather than ERR_PTR(-EPERM) > - did _not_ add it ovl_can_decode_fh() because of changes since last > review, suspect needs to be added to ovl_lower_uuid_ok()? > > v8 + v9: > - rebase > > v7: > - This time for realz > > v6: > - rebase > > v5: > - dependency of "overlayfs: override_creds=off option bypass creator_cred" > > --- > fs/overlayfs/namei.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c > index e9717c2f7d45..9702f0d5309d 100644 > --- a/fs/overlayfs/namei.c > +++ b/fs/overlayfs/namei.c > @@ -161,6 +161,9 @@ struct dentry *ovl_decode_real_fh(struct ovl_fh *fh, struct vfsmount *mnt, > if (!uuid_equal(&fh->uuid, &mnt->mnt_sb->s_uuid)) > return NULL; > > + if (!capable(CAP_DAC_READ_SEARCH)) > + return NULL; > + Shouldn't this return EPERM? > bytes = (fh->len - offsetof(struct ovl_fh, fid)); > real = exportfs_decode_fh(mnt, (struct fid *)fh->fid, > bytes >> 2, (int)fh->type, > -- > 2.23.0.866.gb869b98d4c-goog >
