From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Oliver Hartkopp , "David S. Miller" , Kamal Mostafa Subject: [PATCH 3.8 119/124] fib_frontend: fix possible NULL pointer dereference Date: Mon, 10 Feb 2014 11:40:59 -0800 Message-Id: <1392061264-28124-120-git-send-email-kamal@canonical.com> In-Reply-To: <1392061264-28124-1-git-send-email-kamal@canonical.com> References: <1392061264-28124-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.8.13.18 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Hartkopp [ Upstream commit a0065f266a9b5d51575535a25c15ccbeed9a9966 ] The two commits 0115e8e30d (net: remove delay at device dismantle) and 748e2d9396a (net: reinstate rtnl in call_netdevice_notifiers()) silently removed a NULL pointer check for in_dev since Linux 3.7. This patch re-introduces this check as it causes crashing the kernel when setting small mtu values on non-ip capable netdevices. Signed-off-by: Oliver Hartkopp Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Kamal Mostafa --- net/ipv4/fib_frontend.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 5cd75e2..93ea4a1 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1052,6 +1052,8 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo } in_dev = __in_dev_get_rtnl(dev); + if (!in_dev) + return NOTIFY_DONE; switch (event) { case NETDEV_UP: -- 1.8.3.2