diff options
author | Eric Dumazet <edumazet@google.com> | 2021-03-29 12:25:22 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-22 11:40:55 +0200 |
commit | 3c24dbd358bf130da47034ffdb36c4610ed4a92a (patch) | |
tree | 6ca6ffa4e0e6681bc8022e25f730ae8561ba18a1 | |
parent | b18b1548cb4e4cb1e9223dc2594838d4a815e705 (diff) |
sit: proper dev_{hold|put} in ndo_[un]init methods
commit 6289a98f0817a4a457750d6345e754838eae9439 upstream.
After adopting CONFIG_PCPU_DEV_REFCNT=n option, syzbot was able to trigger
a warning [1]
Issue here is that:
- all dev_put() should be paired with a corresponding prior dev_hold().
- A driver doing a dev_put() in its ndo_uninit() MUST also
do a dev_hold() in its ndo_init(), only when ndo_init()
is returning 0.
Otherwise, register_netdevice() would call ndo_uninit()
in its error path and release a refcount too soon.
Fixes: 919067cc845f ("net: add CONFIG_PCPU_DEV_REFCNT")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | net/ipv6/sit.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 146ba7fa5bf6..22edda1f72d0 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -218,8 +218,6 @@ static int ipip6_tunnel_create(struct net_device *dev) ipip6_tunnel_clone_6rd(dev, sitn); - dev_hold(dev); - ipip6_tunnel_link(sitn, t); return 0; @@ -1456,7 +1454,7 @@ static int ipip6_tunnel_init(struct net_device *dev) dev->tstats = NULL; return err; } - + dev_hold(dev); return 0; } |