lkml.org 
[lkml]   [2013]   [Sep]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH net] tuntap: correctly handle error in tun_set_iff()
    On Wed, Sep 11, 2013 at 05:55:04AM -0400, Jason Wang wrote:
    >
    >
    > ----- Original Message -----
    > > On Wed, Sep 11, 2013 at 04:24:05PM +0800, Jason Wang wrote:
    > > > Commit c8d68e6be1c3b242f1c598595830890b65cea64a (tuntap: multiqueue
    > > > support)
    > > > only call free_netdev() on err in tun_set_iff(). This causes several
    > > > issues:
    > > >
    > > > - memory of tun security were leaked
    > >
    > > Not just tun security - sock reference too (didn't detach)
    > >
    >
    > Yes, I mention it in the next item.

    That line's a bit too long btw.
    Keep it under 70 chars for commit logs.

    > > > - use after free since the flow gc timer was not deleted and the tfile were
    > > > not
    > > > detached
    > > >
    > > > This patch solves the above issues.
    > > >
    > > > Reported-by: Wannes Rombouts <wannes.rombouts@epitech.eu>
    > > > Cc: Michael S. Tsirkin <mst@redhat.com>
    > > > Signed-off-by: Jason Wang <jasowang@redhat.com>
    > > > ---
    > > > The patch were also needed for stable 3.8+.
    > > > ---
    > > > drivers/net/tun.c | 9 +++++++--
    > > > 1 files changed, 7 insertions(+), 2 deletions(-)
    > > >
    > > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c
    > > > index a639de8..e5fb5d3 100644
    > > > --- a/drivers/net/tun.c
    > > > +++ b/drivers/net/tun.c
    > > > @@ -1641,11 +1641,11 @@ static int tun_set_iff(struct net *net, struct file
    > > > *file, struct ifreq *ifr)
    > > > INIT_LIST_HEAD(&tun->disabled);
    > > > err = tun_attach(tun, file, false);
    > > > if (err < 0)
    > > > - goto err_free_dev;
    > > > + goto err_free_flow;
    > > >
    > > > err = register_netdevice(tun->dev);
    > > > if (err < 0)
    > > > - goto err_free_dev;
    > > > + goto err_detach;
    > > >
    > > > if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) ||
    > > > device_create_file(&tun->dev->dev, &dev_attr_owner) ||
    > > > @@ -1689,6 +1689,11 @@ static int tun_set_iff(struct net *net, struct file
    > > > *file, struct ifreq *ifr)
    > > > strcpy(ifr->ifr_name, tun->dev->name);
    > > > return 0;
    > > >
    > > > +err_detach:
    > > > + tun_detach_all(dev);
    > > > +err_free_flow:
    > > > + tun_flow_uninit(tun);
    > > > + security_tun_dev_free_security(tun->security);
    > >
    > > This bit looks wrong: if flow_init fails, we
    > > need security_tun_dev_free_security, don't we?
    > > I think we need:
    > > +err_free_sec: security_tun_dev_free_security(tun->security);
    > > and goto here on flow_init failures.
    >
    > tun_flow_init() always succeed. So we're ok here.

    True. So please make it return void then.

    > >
    > > > err_free_dev:
    > >
    > > Pls shift this one 1 space left for consistency.
    > >
    >
    > Ok.
    > > > free_netdev(dev);
    > > > return err;
    > > > --
    > > > 1.7.1
    > > --
    > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    > > the body of a message to majordomo@vger.kernel.org
    > > More majordomo info at http://vger.kernel.org/majordomo-info.html
    > > Please read the FAQ at http://www.tux.org/lkml/
    > >


    \
     
     \ /
      Last update: 2013-09-11 12:41    [W:3.391 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site