From: Xin Long <lucien.xin(a)gmail.com>
commit eae5783908042a762c24e1bd11876edb91d314b1 upstream.
This patch fixes the problems below:
1. In non-shutdown_ack_sent states: in sctp_sf_do_5_1B_init() and
sctp_sf_do_5_2_2_dupinit():
chunk length check should be done before any checks that may cause
to send abort, as making packet for abort will access the init_tag
from init_hdr in sctp_ootb_pkt_new().
2. In shutdown_ack_sent state: in sctp_sf_do_9_2_reshutack():
The same checks as does in sctp_sf_do_5_2_2_dupinit() is needed
for sctp_sf_do_9_2_reshutack().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long <lucien.xin(a)gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner(a)gmail.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
[OP: adjusted context for 4.14]
Signed-off-by: Ovidiu Panait <ovidiu.panait(a)windriver.com>
---
CVE-2021-3772 patchset consists of 7 fixes:
[1] 4f7019c7eb33 ("sctp: use init_tag from inithdr for ABORT chunk")
[2] eae578390804 ("sctp: fix the processing for INIT chunk")
[3] 438b95a7c98f ("sctp: fix the processing for INIT_ACK chunk")
[4] a64b341b8695 ("sctp: fix the processing for COOKIE_ECHO chunk")
[5] aa0f697e4528 ("sctp: add vtag check in sctp_sf_violation")
[6] ef16b1734f0a ("sctp: add vtag check in sctp_sf_do_8_5_1_E_sa")
[7] 9d02831e517a ("sctp: add vtag check in sctp_sf_ootb")
This series contains backports for [2] and [3], which are the only fixes
missing from 4.14-stable. Only small contextual adjustments were made.
net/sctp/sm_statefuns.c | 71 ++++++++++++++++++++++++++---------------
1 file changed, 46 insertions(+), 25 deletions(-)
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index b26067798dbf..91aecc3449d2 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -161,6 +161,12 @@ static enum sctp_disposition __sctp_sf_do_9_1_abort(
void *arg,
struct sctp_cmd_seq *commands);
+static enum sctp_disposition
+__sctp_sf_do_9_2_reshutack(struct net *net, const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ const union sctp_subtype type, void *arg,
+ struct sctp_cmd_seq *commands);
+
/* Small helper function that checks if the chunk length
* is of the appropriate length. The 'required_length' argument
* is set to be the size of a specific chunk we are testing.
@@ -337,6 +343,14 @@ enum sctp_disposition sctp_sf_do_5_1B_init(struct net *net,
if (!chunk->singleton)
return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+ /* Make sure that the INIT chunk has a valid length.
+ * Normally, this would cause an ABORT with a Protocol Violation
+ * error, but since we don't have an association, we'll
+ * just discard the packet.
+ */
+ if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk)))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
/* If the packet is an OOTB packet which is temporarily on the
* control endpoint, respond with an ABORT.
*/
@@ -351,14 +365,6 @@ enum sctp_disposition sctp_sf_do_5_1B_init(struct net *net,
if (chunk->sctp_hdr->vtag != 0)
return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
- /* Make sure that the INIT chunk has a valid length.
- * Normally, this would cause an ABORT with a Protocol Violation
- * error, but since we don't have an association, we'll
- * just discard the packet.
- */
- if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk)))
- return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
-
/* If the INIT is coming toward a closing socket, we'll send back
* and ABORT. Essentially, this catches the race of INIT being
* backloged to the socket at the same time as the user isses close().
@@ -1460,19 +1466,16 @@ static enum sctp_disposition sctp_sf_do_unexpected_init(
if (!chunk->singleton)
return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+ /* Make sure that the INIT chunk has a valid length. */
+ if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk)))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
/* 3.1 A packet containing an INIT chunk MUST have a zero Verification
* Tag.
*/
if (chunk->sctp_hdr->vtag != 0)
return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
- /* Make sure that the INIT chunk has a valid length.
- * In this case, we generate a protocol violation since we have
- * an association established.
- */
- if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk)))
- return sctp_sf_violation_chunklen(net, ep, asoc, type, arg,
- commands);
/* Grab the INIT header. */
chunk->subh.init_hdr = (struct sctp_inithdr *)chunk->skb->data;
@@ -1787,9 +1790,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_a(
* its peer.
*/
if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) {
- disposition = sctp_sf_do_9_2_reshutack(net, ep, asoc,
- SCTP_ST_CHUNK(chunk->chunk_hdr->type),
- chunk, commands);
+ disposition = __sctp_sf_do_9_2_reshutack(net, ep, asoc,
+ SCTP_ST_CHUNK(chunk->chunk_hdr->type),
+ chunk, commands);
if (SCTP_DISPOSITION_NOMEM == disposition)
goto nomem;
@@ -2847,13 +2850,11 @@ enum sctp_disposition sctp_sf_do_9_2_shut_ctsn(
* that belong to this association, it should discard the INIT chunk and
* retransmit the SHUTDOWN ACK chunk.
*/
-enum sctp_disposition sctp_sf_do_9_2_reshutack(
- struct net *net,
- const struct sctp_endpoint *ep,
- const struct sctp_association *asoc,
- const union sctp_subtype type,
- void *arg,
- struct sctp_cmd_seq *commands)
+static enum sctp_disposition
+__sctp_sf_do_9_2_reshutack(struct net *net, const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ const union sctp_subtype type, void *arg,
+ struct sctp_cmd_seq *commands)
{
struct sctp_chunk *chunk = arg;
struct sctp_chunk *reply;
@@ -2887,6 +2888,26 @@ enum sctp_disposition sctp_sf_do_9_2_reshutack(
return SCTP_DISPOSITION_NOMEM;
}
+enum sctp_disposition
+sctp_sf_do_9_2_reshutack(struct net *net, const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ const union sctp_subtype type, void *arg,
+ struct sctp_cmd_seq *commands)
+{
+ struct sctp_chunk *chunk = arg;
+
+ if (!chunk->singleton)
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
+ if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk)))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
+ if (chunk->sctp_hdr->vtag != 0)
+ return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands);
+
+ return __sctp_sf_do_9_2_reshutack(net, ep, asoc, type, arg, commands);
+}
+
/*
* sctp_sf_do_ecn_cwr
*
--
2.25.1
From: "Michael S. Tsirkin" <mst(a)redhat.com>
[ Upstream commit 0e7174b9d5877130fec41fb4a16e0c2ee4958d44 ]
A common pattern for device reset is currently:
vdev->config->reset(vdev);
.. cleanup ..
reset prevents new interrupts from arriving and waits for interrupt
handlers to finish.
However if - as is common - the handler queues a work request which is
flushed during the cleanup stage, we have code adding buffers / trying
to get buffers while device is reset. Not good.
This was reproduced by running
modprobe virtio_console
modprobe -r virtio_console
in a loop.
Fix this up by calling virtio_break_device + flush before reset.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1786239
Signed-off-by: Michael S. Tsirkin <mst(a)redhat.com>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
drivers/char/virtio_console.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 2632b0fdb1b5..a6b6dc204c1f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -2004,6 +2004,13 @@ static void virtcons_remove(struct virtio_device *vdev)
list_del(&portdev->list);
spin_unlock_irq(&pdrvdata_lock);
+ /* Device is going away, exit any polling for buffers */
+ virtio_break_device(vdev);
+ if (use_multiport(portdev))
+ flush_work(&portdev->control_work);
+ else
+ flush_work(&portdev->config_work);
+
/* Disable interrupts for vqs */
vdev->config->reset(vdev);
/* Finish up work that's lined up */
--
2.34.1
From: "Michael S. Tsirkin" <mst(a)redhat.com>
[ Upstream commit 0e7174b9d5877130fec41fb4a16e0c2ee4958d44 ]
A common pattern for device reset is currently:
vdev->config->reset(vdev);
.. cleanup ..
reset prevents new interrupts from arriving and waits for interrupt
handlers to finish.
However if - as is common - the handler queues a work request which is
flushed during the cleanup stage, we have code adding buffers / trying
to get buffers while device is reset. Not good.
This was reproduced by running
modprobe virtio_console
modprobe -r virtio_console
in a loop.
Fix this up by calling virtio_break_device + flush before reset.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1786239
Signed-off-by: Michael S. Tsirkin <mst(a)redhat.com>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
drivers/char/virtio_console.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 0fb3a8e62e62..2140d401523f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -2001,6 +2001,13 @@ static void virtcons_remove(struct virtio_device *vdev)
list_del(&portdev->list);
spin_unlock_irq(&pdrvdata_lock);
+ /* Device is going away, exit any polling for buffers */
+ virtio_break_device(vdev);
+ if (use_multiport(portdev))
+ flush_work(&portdev->control_work);
+ else
+ flush_work(&portdev->config_work);
+
/* Disable interrupts for vqs */
vdev->config->reset(vdev);
/* Finish up work that's lined up */
--
2.34.1
From: Lina Wang <lina.wang(a)mediatek.com>
[ Upstream commit 4ff2980b6bd2aa6b4ded3ce3b7c0ccfab29980af ]
in tunnel mode, if outer interface(ipv4) is less, it is easily to let
inner IPV6 mtu be less than 1280. If so, a Packet Too Big ICMPV6 message
is received. When send again, packets are fragmentized with 1280, they
are still rejected with ICMPV6(Packet Too Big) by xfrmi_xmit2().
According to RFC4213 Section3.2.2:
if (IPv4 path MTU - 20) is less than 1280
if packet is larger than 1280 bytes
Send ICMPv6 "packet too big" with MTU=1280
Drop packet
else
Encapsulate but do not set the Don't Fragment
flag in the IPv4 header. The resulting IPv4
packet might be fragmented by the IPv4 layer
on the encapsulator or by some router along
the IPv4 path.
endif
else
if packet is larger than (IPv4 path MTU - 20)
Send ICMPv6 "packet too big" with
MTU = (IPv4 path MTU - 20).
Drop packet.
else
Encapsulate and set the Don't Fragment flag
in the IPv4 header.
endif
endif
Packets should be fragmentized with ipv4 outer interface, so change it.
After it is fragemtized with ipv4, there will be double fragmenation.
No.48 & No.51 are ipv6 fragment packets, No.48 is double fragmentized,
then tunneled with IPv4(No.49& No.50), which obey spec. And received peer
cannot decrypt it rightly.
48 2002::10 2002::11 1296(length) IPv6 fragment (off=0 more=y ident=0xa20da5bc nxt=50)
49 0x0000 (0) 2002::10 2002::11 1304 IPv6 fragment (off=0 more=y ident=0x7448042c nxt=44)
50 0x0000 (0) 2002::10 2002::11 200 ESP (SPI=0x00035000)
51 2002::10 2002::11 180 Echo (ping) request
52 0x56dc 2002::10 2002::11 248 IPv6 fragment (off=1232 more=n ident=0xa20da5bc nxt=50)
xfrm6_noneed_fragment has fixed above issues. Finally, it acted like below:
1 0x6206 192.168.1.138 192.168.1.1 1316 Fragmented IP protocol (proto=Encap Security Payload 50, off=0, ID=6206) [Reassembled in #2]
2 0x6206 2002::10 2002::11 88 IPv6 fragment (off=0 more=y ident=0x1f440778 nxt=50)
3 0x0000 2002::10 2002::11 248 ICMPv6 Echo (ping) request
Signed-off-by: Lina Wang <lina.wang(a)mediatek.com>
Signed-off-by: Steffen Klassert <steffen.klassert(a)secunet.com>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
net/ipv6/xfrm6_output.c | 16 ++++++++++++++++
net/xfrm/xfrm_interface.c | 5 ++++-
2 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index b5941c9475f3..fbcec4827071 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -142,6 +142,19 @@ static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buf
return x->outer_mode->afinfo->output_finish(sk, skb);
}
+static int xfrm6_noneed_fragment(struct sk_buff *skb)
+{
+ struct frag_hdr *fh;
+ u8 prevhdr = ipv6_hdr(skb)->nexthdr;
+
+ if (prevhdr != NEXTHDR_FRAGMENT)
+ return 0;
+ fh = (struct frag_hdr *)(skb->data + sizeof(struct ipv6hdr));
+ if (fh->nexthdr == NEXTHDR_ESP || fh->nexthdr == NEXTHDR_AUTH)
+ return 1;
+ return 0;
+}
+
static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
@@ -170,6 +183,9 @@ static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
xfrm6_local_rxpmtu(skb, mtu);
kfree_skb(skb);
return -EMSGSIZE;
+ } else if (toobig && xfrm6_noneed_fragment(skb)) {
+ skb->ignore_df = 1;
+ goto skip_frag;
} else if (!skb->ignore_df && toobig && skb->sk) {
xfrm_local_error(skb, mtu);
kfree_skb(skb);
diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index 1ae8caca28a0..3c642328a117 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -300,7 +300,10 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
- icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ if (skb->len > 1280)
+ icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+ else
+ goto xmit;
} else {
if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
goto xmit;
--
2.34.1