linux-kernel - [PATCH net] caif: Fix crash due to uninitialized net name-space.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1327523631-3480-1-git-send-email-sjur.brandeland@stericsson.com>
Date:	Wed, 25 Jan 2012 21:33:51 +0100
From:	Sjur Brændeland <sjur.brandeland@...ricsson.com>
To:	levinsasha928@...il.com, netdev@...r.kernel.org,
	davem@...emloft.net
Cc:	linux-kernel@...r.kernel.org, davej@...hat.com, sjurbren@...il.com,
	Sjur Brændeland <sjur.brandeland@...ricsson.com>
Subject: [PATCH net] caif: Fix crash due to uninitialized net name-space.

net_generic() calls BUG_ON() if called with uninitialized
network name-space. Add check if net is initialized before
calling net_generic(). This fixes the following oops:

[  200.752016] kernel BUG at include/net/netns/generic.h:40!
...
[  200.752016]  [<ffffffff825c3cea>] ? get_cfcnfg+0x3a/0x180
[  200.752016]  [<ffffffff821cf0b0>] ? lockdep_rtnl_is_held+0x10/0x20
[  200.752016]  [<ffffffff825c41be>] caif_device_notify+0x2e/0x530
[  200.752016]  [<ffffffff810d61b7>] notifier_call_chain+0x67/0x110
[  200.752016]  [<ffffffff810d67c1>] raw_notifier_call_chain+0x11/0x20
[  200.752016]  [<ffffffff821bae82>] call_netdevice_notifiers+0x32/0x60
[  200.752016]  [<ffffffff821c2b26>] register_netdevice+0x196/0x300
[  200.752016]  [<ffffffff821c2ca9>] register_netdev+0x19/0x30
[  200.752016]  [<ffffffff81c1c67a>] loopback_net_init+0x4a/0xa0
[  200.752016]  [<ffffffff821b5e62>] ops_init+0x42/0x180
[  200.752016]  [<ffffffff821b600b>] setup_net+0x6b/0x100
[  200.752016]  [<ffffffff821b6466>] copy_net_ns+0x86/0x110
[  200.752016]  [<ffffffff810d5789>] create_new_namespaces+0xd9/0x190

Signed-off-by: Sjur Brændeland <sjur.brandeland@...ricsson.com>
Tested-by: Sasha Levin <levinsasha928@...il.com>

---

Hi Sasha and Dave,

[Sasha]
>Works for me.
Thank you Sasha for reporting this bug and testing my patch,
I appreciate it.

[Dave]
>Please post all networking patches CC:'d
Sorry, I missed the obvious.
I'm resending the same patch as yesterday, this time to:netdev
and with "Tested-by: Sasha". Please apply to net.

Thanks,
Sjur

 net/caif/caif_dev.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index 673728a..6110ade 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -371,6 +371,14 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
 	struct cflayer *layer, *link_support;
 	int head_room = 0;
 	struct caif_device_entry_list *caifdevs;
+	int len;
+
+	rcu_read_lock();
+	len = rcu_dereference(dev_net(dev)->gen)->len;
+	rcu_read_unlock();
+
+	if (caif_net_id == 0 || caif_net_id > len)
+		return 0;
 
 	cfg = get_cfcnfg(dev_net(dev));
 	caifdevs = caif_device_list(dev_net(dev));
-- 
1.7.0.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/