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[3.8.y.z,extended,stable] Patch "selinux: correct locking in selinux_netlbl_socket_connect)" has been added to staging queue

Message ID 1386371281-28605-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa Dec. 6, 2013, 11:08 p.m. UTC
This is a note to let you know that I have just added a patch titled

    selinux: correct locking in selinux_netlbl_socket_connect)

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.14.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

From 4edafee62dd554a5560251ceb552388d100a3651 Mon Sep 17 00:00:00 2001
From: Paul Moore <pmoore@redhat.com>
Date: Thu, 26 Sep 2013 17:00:46 -0400
Subject: selinux: correct locking in selinux_netlbl_socket_connect)

commit 42d64e1add3a1ce8a787116036163b8724362145 upstream.

The SELinux/NetLabel glue code has a locking bug that affects systems
with NetLabel enabled, see the kernel error message below.  This patch
corrects this problem by converting the bottom half socket lock to a
more conventional, and correct for this call-path, lock_sock() call.

 ===============================
 [ INFO: suspicious RCU usage. ]
 3.11.0-rc3+ #19 Not tainted
 -------------------------------
 net/ipv4/cipso_ipv4.c:1928 suspicious rcu_dereference_protected() usage!

 other info that might help us debug this:

 rcu_scheduler_active = 1, debug_locks = 0
 2 locks held by ping/731:
  #0:  (slock-AF_INET/1){+.-...}, at: [...] selinux_netlbl_socket_connect
  #1:  (rcu_read_lock){.+.+..}, at: [<...>] netlbl_conn_setattr

 stack backtrace:
 CPU: 1 PID: 731 Comm: ping Not tainted 3.11.0-rc3+ #19
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  0000000000000001 ffff88006f659d28 ffffffff81726b6a ffff88003732c500
  ffff88006f659d58 ffffffff810e4457 ffff88006b845a00 0000000000000000
  000000000000000c ffff880075aa2f50 ffff88006f659d90 ffffffff8169bec7
 Call Trace:
  [<ffffffff81726b6a>] dump_stack+0x54/0x74
  [<ffffffff810e4457>] lockdep_rcu_suspicious+0xe7/0x120
  [<ffffffff8169bec7>] cipso_v4_sock_setattr+0x187/0x1a0
  [<ffffffff8170f317>] netlbl_conn_setattr+0x187/0x190
  [<ffffffff8170f195>] ? netlbl_conn_setattr+0x5/0x190
  [<ffffffff8131ac9e>] selinux_netlbl_socket_connect+0xae/0xc0
  [<ffffffff81303025>] selinux_socket_connect+0x135/0x170
  [<ffffffff8119d127>] ? might_fault+0x57/0xb0
  [<ffffffff812fb146>] security_socket_connect+0x16/0x20
  [<ffffffff815d3ad3>] SYSC_connect+0x73/0x130
  [<ffffffff81739a85>] ? sysret_check+0x22/0x5d
  [<ffffffff810e5e2d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
  [<ffffffff81373d4e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
  [<ffffffff815d52be>] SyS_connect+0xe/0x10
  [<ffffffff81739a59>] system_call_fastpath+0x16/0x1b

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 security/selinux/netlabel.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--
1.8.3.2
diff mbox

Patch

diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c
index da4b8b2..6235d05 100644
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -442,8 +442,7 @@  int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr)
 	    sksec->nlbl_state != NLBL_CONNLABELED)
 		return 0;

-	local_bh_disable();
-	bh_lock_sock_nested(sk);
+	lock_sock(sk);

 	/* connected sockets are allowed to disconnect when the address family
 	 * is set to AF_UNSPEC, if that is what is happening we want to reset
@@ -464,7 +463,6 @@  int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr)
 		sksec->nlbl_state = NLBL_CONNLABELED;

 socket_connect_return:
-	bh_unlock_sock(sk);
-	local_bh_enable();
+	release_sock(sk);
 	return rc;
 }