[meta-freescale] [meta-fsl-ppc krogoth][PATCH] kernel: CVE-2015-8767
Sona Sarmadi
sona.sarmadi at enea.com
Thu Nov 24 22:47:57 PST 2016
Fixes SCTP denial of service during timeout.
A remote attacker could use this flaw to prevent further
connections to be accepted by the SCTP server running on
the system, resulting in a denial of service.
References:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-8767
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2015-8767
Upstream fix:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/patch/?id=6b1a4c8425acde6b3725e9ca5dc7af544c656fda
Signed-off-by: Sona Sarmadi <sona.sarmadi at enea.com>
---
recipes-kernel/linux/files/CVE-2015-8767.patch | 200 +++++++++++++++++++++++++
recipes-kernel/linux/linux-qoriq_3.12.bb | 1 +
2 files changed, 201 insertions(+)
create mode 100644 recipes-kernel/linux/files/CVE-2015-8767.patch
diff --git a/recipes-kernel/linux/files/CVE-2015-8767.patch b/recipes-kernel/linux/files/CVE-2015-8767.patch
new file mode 100644
index 0000000..b3903ce
--- /dev/null
+++ b/recipes-kernel/linux/files/CVE-2015-8767.patch
@@ -0,0 +1,200 @@
+From 6b1a4c8425acde6b3725e9ca5dc7af544c656fda Mon Sep 17 00:00:00 2001
+From: Karl Heiss <kheiss at gmail.com>
+Date: Thu, 24 Sep 2015 12:15:07 -0400
+Subject: sctp: Prevent soft lockup when sctp_accept() is called during a
+ timeout event
+
+commit 635682a14427d241bab7bbdeebb48a7d7b91638e upstream.
+
+A case can occur when sctp_accept() is called by the user during
+a heartbeat timeout event after the 4-way handshake. Since
+sctp_assoc_migrate() changes both assoc->base.sk and assoc->ep, the
+bh_sock_lock in sctp_generate_heartbeat_event() will be taken with
+the listening socket but released with the new association socket.
+The result is a deadlock on any future attempts to take the listening
+socket lock.
+
+Note that this race can occur with other SCTP timeouts that take
+the bh_lock_sock() in the event sctp_accept() is called.
+
+ BUG: soft lockup - CPU#9 stuck for 67s! [swapper:0]
+ ...
+ RIP: 0010:[<ffffffff8152d48e>] [<ffffffff8152d48e>] _spin_lock+0x1e/0x30
+ RSP: 0018:ffff880028323b20 EFLAGS: 00000206
+ RAX: 0000000000000002 RBX: ffff880028323b20 RCX: 0000000000000000
+ RDX: 0000000000000000 RSI: ffff880028323be0 RDI: ffff8804632c4b48
+ RBP: ffffffff8100bb93 R08: 0000000000000000 R09: 0000000000000000
+ R10: ffff880610662280 R11: 0000000000000100 R12: ffff880028323aa0
+ R13: ffff8804383c3880 R14: ffff880028323a90 R15: ffffffff81534225
+ FS: 0000000000000000(0000) GS:ffff880028320000(0000) knlGS:0000000000000000
+ CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
+ CR2: 00000000006df528 CR3: 0000000001a85000 CR4: 00000000000006e0
+ DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
+ DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
+ Process swapper (pid: 0, threadinfo ffff880616b70000, task ffff880616b6cab0)
+ Stack:
+ ffff880028323c40 ffffffffa01c2582 ffff880614cfb020 0000000000000000
+ <d> 0100000000000000 00000014383a6c44 ffff8804383c3880 ffff880614e93c00
+ <d> ffff880614e93c00 0000000000000000 ffff8804632c4b00 ffff8804383c38b8
+ Call Trace:
+ <IRQ>
+ [<ffffffffa01c2582>] ? sctp_rcv+0x492/0xa10 [sctp]
+ [<ffffffff8148c559>] ? nf_iterate+0x69/0xb0
+ [<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
+ [<ffffffff8148c716>] ? nf_hook_slow+0x76/0x120
+ [<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
+ [<ffffffff8149757d>] ? ip_local_deliver_finish+0xdd/0x2d0
+ [<ffffffff81497808>] ? ip_local_deliver+0x98/0xa0
+ [<ffffffff81496ccd>] ? ip_rcv_finish+0x12d/0x440
+ [<ffffffff81497255>] ? ip_rcv+0x275/0x350
+ [<ffffffff8145cfeb>] ? __netif_receive_skb+0x4ab/0x750
+ ...
+
+With lockdep debugging:
+
+ =====================================
+ [ BUG: bad unlock balance detected! ]
+ -------------------------------------
+ CslRx/12087 is trying to release lock (slock-AF_INET) at:
+ [<ffffffffa01bcae0>] sctp_generate_timeout_event+0x40/0xe0 [sctp]
+ but there are no more locks to release!
+
+ other info that might help us debug this:
+ 2 locks held by CslRx/12087:
+ #0: (&asoc->timers[i]){+.-...}, at: [<ffffffff8108ce1f>] run_timer_softirq+0x16f/0x3e0
+ #1: (slock-AF_INET){+.-...}, at: [<ffffffffa01bcac3>] sctp_generate_timeout_event+0x23/0xe0 [sctp]
+
+Ensure the socket taken is also the same one that is released by
+saving a copy of the socket before entering the timeout event
+critical section.
+
+CVE: CVE-2015-8767
+Upstream-Status: Backport
+
+Signed-off-by: Karl Heiss <kheiss at gmail.com>
+Signed-off-by: David S. Miller <davem at davemloft.net>
+Cc: Ben Hutchings <ben at decadent.org.uk>
+Signed-off-by: Jiri Slaby <jslaby at suse.cz>
+Signed-off-by: Sona Sarmadi <sona.sarmadi at enea.com>
+---
+ net/sctp/sm_sideeffect.c | 42 +++++++++++++++++++++++-------------------
+ 1 file changed, 23 insertions(+), 19 deletions(-)
+
+diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
+index 1a6eef3..ae66c9f 100644
+--- a/net/sctp/sm_sideeffect.c
++++ b/net/sctp/sm_sideeffect.c
+@@ -245,12 +245,13 @@ void sctp_generate_t3_rtx_event(unsigned long peer)
+ int error;
+ struct sctp_transport *transport = (struct sctp_transport *) peer;
+ struct sctp_association *asoc = transport->asoc;
+- struct net *net = sock_net(asoc->base.sk);
++ struct sock *sk = asoc->base.sk;
++ struct net *net = sock_net(sk);
+
+ /* Check whether a task is in the sock. */
+
+- sctp_bh_lock_sock(asoc->base.sk);
+- if (sock_owned_by_user(asoc->base.sk)) {
++ sctp_bh_lock_sock(sk);
++ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy\n", __func__);
+
+ /* Try again later. */
+@@ -273,10 +274,10 @@ void sctp_generate_t3_rtx_event(unsigned long peer)
+ transport, GFP_ATOMIC);
+
+ if (error)
+- asoc->base.sk->sk_err = -error;
++ sk->sk_err = -error;
+
+ out_unlock:
+- sctp_bh_unlock_sock(asoc->base.sk);
++ sctp_bh_unlock_sock(sk);
+ sctp_transport_put(transport);
+ }
+
+@@ -286,11 +287,12 @@ out_unlock:
+ static void sctp_generate_timeout_event(struct sctp_association *asoc,
+ sctp_event_timeout_t timeout_type)
+ {
+- struct net *net = sock_net(asoc->base.sk);
++ struct sock *sk = asoc->base.sk;
++ struct net *net = sock_net(sk);
+ int error = 0;
+
+- sctp_bh_lock_sock(asoc->base.sk);
+- if (sock_owned_by_user(asoc->base.sk)) {
++ sctp_bh_lock_sock(sk);
++ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy: timer %d\n", __func__,
+ timeout_type);
+
+@@ -313,10 +315,10 @@ static void sctp_generate_timeout_event(struct sctp_association *asoc,
+ (void *)timeout_type, GFP_ATOMIC);
+
+ if (error)
+- asoc->base.sk->sk_err = -error;
++ sk->sk_err = -error;
+
+ out_unlock:
+- sctp_bh_unlock_sock(asoc->base.sk);
++ sctp_bh_unlock_sock(sk);
+ sctp_association_put(asoc);
+ }
+
+@@ -366,10 +368,11 @@ void sctp_generate_heartbeat_event(unsigned long data)
+ int error = 0;
+ struct sctp_transport *transport = (struct sctp_transport *) data;
+ struct sctp_association *asoc = transport->asoc;
+- struct net *net = sock_net(asoc->base.sk);
++ struct sock *sk = asoc->base.sk;
++ struct net *net = sock_net(sk);
+
+- sctp_bh_lock_sock(asoc->base.sk);
+- if (sock_owned_by_user(asoc->base.sk)) {
++ sctp_bh_lock_sock(sk);
++ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy\n", __func__);
+
+ /* Try again later. */
+@@ -390,10 +393,10 @@ void sctp_generate_heartbeat_event(unsigned long data)
+ transport, GFP_ATOMIC);
+
+ if (error)
+- asoc->base.sk->sk_err = -error;
++ sk->sk_err = -error;
+
+ out_unlock:
+- sctp_bh_unlock_sock(asoc->base.sk);
++ sctp_bh_unlock_sock(sk);
+ sctp_transport_put(transport);
+ }
+
+@@ -404,10 +407,11 @@ void sctp_generate_proto_unreach_event(unsigned long data)
+ {
+ struct sctp_transport *transport = (struct sctp_transport *) data;
+ struct sctp_association *asoc = transport->asoc;
+- struct net *net = sock_net(asoc->base.sk);
++ struct sock *sk = asoc->base.sk;
++ struct net *net = sock_net(sk);
+
+- sctp_bh_lock_sock(asoc->base.sk);
+- if (sock_owned_by_user(asoc->base.sk)) {
++ sctp_bh_lock_sock(sk);
++ if (sock_owned_by_user(sk)) {
+ pr_debug("%s: sock is busy\n", __func__);
+
+ /* Try again later. */
+@@ -428,7 +432,7 @@ void sctp_generate_proto_unreach_event(unsigned long data)
+ asoc->state, asoc->ep, asoc, transport, GFP_ATOMIC);
+
+ out_unlock:
+- sctp_bh_unlock_sock(asoc->base.sk);
++ sctp_bh_unlock_sock(sk);
+ sctp_association_put(asoc);
+ }
+
+--
+cgit v0.12
+
diff --git a/recipes-kernel/linux/linux-qoriq_3.12.bb b/recipes-kernel/linux/linux-qoriq_3.12.bb
index 9cfdfa6..e3ba079 100644
--- a/recipes-kernel/linux/linux-qoriq_3.12.bb
+++ b/recipes-kernel/linux/linux-qoriq_3.12.bb
@@ -6,5 +6,6 @@ SRC_URI = "git://git.freescale.com/ppc/sdk/linux.git;branch=sdk-v1.9.x \
file://0001-powerpc-Align-TOC-to-256-bytes.patch \
file://Trusty-SRU-ipc-fix-compat-msgrcv-with-negative-msgtyp.patch \
file://CVE-2015-8539.patch \
+ file://CVE-2015-8767.patch \
"
SRCREV = "43cecda943a6c40a833b588801b0929e8bd48813"
--
1.9.1
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