Re: [PATCH 5.11 13/31] net: bonding: fix error return code of bond_neigh_init()

[Jiri Kosina <jikos@kernel.org>]

On Fri, 19 Mar 2021, Jiri Kosina wrote:

> > [ Upstream commit 2055a99da8a253a357bdfd359b3338ef3375a26c ]
> > 
> > When slave is NULL or slave_ops->ndo_neigh_setup is NULL, no error
> > return code of bond_neigh_init() is assigned.
> > To fix this bug, ret is assigned with -EINVAL in these cases.
> > 
> > Fixes: 9e99bfefdbce ("bonding: fix bond_neigh_init()")
> > Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
> > Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
> > Signed-off-by: David S. Miller <davem@davemloft.net>
> > Signed-off-by: Sasha Levin <sashal@kernel.org>
> > ---
> >  drivers/net/bonding/bond_main.c | 8 ++++++--
> >  1 file changed, 6 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> > index 5fe5232cc3f3..fba6b6d1b430 100644
> > --- a/drivers/net/bonding/bond_main.c
> > +++ b/drivers/net/bonding/bond_main.c
> > @@ -3917,11 +3917,15 @@ static int bond_neigh_init(struct neighbour *n)
> >  
> >  	rcu_read_lock();
> >  	slave = bond_first_slave_rcu(bond);
> > -	if (!slave)
> > +	if (!slave) {
> > +		ret = -EINVAL;
> >  		goto out;
> > +	}
> >  	slave_ops = slave->dev->netdev_ops;
> > -	if (!slave_ops->ndo_neigh_setup)
> > +	if (!slave_ops->ndo_neigh_setup) {
> > +		ret = -EINVAL;
> >  		goto out;
> > +	}
> 
> This patch is completely broken and breaks bonding functionality 
> altogether for me.

... and I just found out that revert is already queued in netdev.git. So 
please drop it from stable queue as well.

-- 
Jiri Kosina
SUSE Labs