On Mon, Oct 2, 2023 at 8:47 AM Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
> On Mon, Oct 2, 2023 at 5:36 AM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
> >
> > d_inode_rcu() is right - we might be in rcu pathwalk;
> > however, OVL_E() hides plain d_inode() on the same dentry...
> >
> > Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
>
> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
>
> However, ovl_lowerstack(oe) does not appear to be stable in RCU walk...
>
Ah, you fixed that in another patch.
If you are going to be sending this to Linus, please add
Fixes: a6ff2bc0be17 ("ovl: use OVL_E() and OVL_E_FLAGS() accessors")
I was going to send some fixes this week anyway, so I can
pick those through the overlayfs tree if you like.
Thanks,
Amir.
> > ---
> > fs/overlayfs/super.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
> > index f09184b865ec..905d3aaf4e55 100644
> > --- a/fs/overlayfs/super.c
> > +++ b/fs/overlayfs/super.c
> > @@ -104,8 +104,8 @@ static int ovl_revalidate_real(struct dentry *d, unsigned int flags, bool weak)
> > static int ovl_dentry_revalidate_common(struct dentry *dentry,
> > unsigned int flags, bool weak)
> > {
> > - struct ovl_entry *oe = OVL_E(dentry);
> > - struct ovl_path *lowerstack = ovl_lowerstack(oe);
> > + struct ovl_entry *oe;
> > + struct ovl_path *lowerstack;
> > struct inode *inode = d_inode_rcu(dentry);
> > struct dentry *upper;
> > unsigned int i;
> > @@ -115,6 +115,8 @@ static int ovl_dentry_revalidate_common(struct dentry *dentry,
> > if (!inode)
> > return -ECHILD;
> >
> > + oe = OVL_I_E(inode);
> > + lowerstack = ovl_lowerstack(oe);
> > upper = ovl_i_dentry_upper(inode);
> > if (upper)
> > ret = ovl_revalidate_real(upper, flags, weak);
> > --
> > 2.39.2
> >
