The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 175e476b8cdf2a4de7432583b49c871345e4f8a1 Mon Sep 17 00:00:00 2001
From: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Date: Mon, 8 Mar 2021 14:24:13 +1300
Subject: [PATCH] netfilter: x_tables: Use correct memory barriers.
When a new table value was assigned, it was followed by a write memory
barrier. This ensured that all writes before this point would complete
before any writes after this point. However, to determine whether the
rules are unused, the sequence counter is read. To ensure that all
writes have been done before these reads, a full memory barrier is
needed, not just a write memory barrier. The same argument applies when
incrementing the counter, before the rules are read.
Changing to using smp_mb() instead of smp_wmb() fixes the kernel panic
reported in cc00bcaa5899 (which is still present), while still
maintaining the same speed of replacing tables.
The smb_mb() barriers potentially slow the packet path, however testing
has shown no measurable change in performance on a 4-core MIPS64
platform.
Fixes: 7f5c6d4f665b ("netfilter: get rid of atomic ops in fast path")
Signed-off-by: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Signed-off-by: Pablo Neira Ayuso <pablo(a)netfilter.org>
---
include/linux/netfilter/x_tables.h | 2 +-
net/netfilter/x_tables.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 5deb099d156d..8ec48466410a 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -376,7 +376,7 @@ static inline unsigned int xt_write_recseq_begin(void)
* since addend is most likely 1
*/
__this_cpu_add(xt_recseq.sequence, addend);
- smp_wmb();
+ smp_mb();
return addend;
}
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 7df3aef39c5c..6bd31a7a27fc 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1389,7 +1389,7 @@ xt_replace_table(struct xt_table *table,
table->private = newinfo;
/* make sure all cpus see new ->private value */
- smp_wmb();
+ smp_mb();
/*
* Even though table entries have now been swapped, other CPU's
--
2.30.1
The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From a188bb5638d41aa99090ebf2f85d3505ab13fba5 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel(a)iogearbox.net>
Date: Wed, 10 Mar 2021 01:38:10 +0100
Subject: [PATCH] net, bpf: Fix ip6ip6 crash with collect_md populated skbs
I ran into a crash where setting up a ip6ip6 tunnel device which was /not/
set to collect_md mode was receiving collect_md populated skbs for xmit.
The BPF prog was populating the skb via bpf_skb_set_tunnel_key() which is
assigning special metadata dst entry and then redirecting the skb to the
device, taking ip6_tnl_start_xmit() -> ipxip6_tnl_xmit() -> ip6_tnl_xmit()
and in the latter it performs a neigh lookup based on skb_dst(skb) where
we trigger a NULL pointer dereference on dst->ops->neigh_lookup() since
the md_dst_ops do not populate neigh_lookup callback with a fake handler.
Transform the md_dst_ops into generic dst_blackhole_ops that can also be
reused elsewhere when needed, and use them for the metadata dst entries as
callback ops.
Also, remove the dst_md_discard{,_out}() ops and rely on dst_discard{,_out}()
from dst_init() which free the skb the same way modulo the splat. Given we
will be able to recover just fine from there, avoid any potential splats
iff this gets ever triggered in future (or worse, panic on warns when set).
Fixes: f38a9eb1f77b ("dst: Metadata destinations")
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/core/dst.c | 31 +++++++++----------------------
1 file changed, 9 insertions(+), 22 deletions(-)
diff --git a/net/core/dst.c b/net/core/dst.c
index 5f6315601776..fb3bcba87744 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -275,37 +275,24 @@ unsigned int dst_blackhole_mtu(const struct dst_entry *dst)
}
EXPORT_SYMBOL_GPL(dst_blackhole_mtu);
-static struct dst_ops md_dst_ops = {
- .family = AF_UNSPEC,
+static struct dst_ops dst_blackhole_ops = {
+ .family = AF_UNSPEC,
+ .neigh_lookup = dst_blackhole_neigh_lookup,
+ .check = dst_blackhole_check,
+ .cow_metrics = dst_blackhole_cow_metrics,
+ .update_pmtu = dst_blackhole_update_pmtu,
+ .redirect = dst_blackhole_redirect,
+ .mtu = dst_blackhole_mtu,
};
-static int dst_md_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
-{
- WARN_ONCE(1, "Attempting to call output on metadata dst\n");
- kfree_skb(skb);
- return 0;
-}
-
-static int dst_md_discard(struct sk_buff *skb)
-{
- WARN_ONCE(1, "Attempting to call input on metadata dst\n");
- kfree_skb(skb);
- return 0;
-}
-
static void __metadata_dst_init(struct metadata_dst *md_dst,
enum metadata_type type, u8 optslen)
-
{
struct dst_entry *dst;
dst = &md_dst->dst;
- dst_init(dst, &md_dst_ops, NULL, 1, DST_OBSOLETE_NONE,
+ dst_init(dst, &dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE,
DST_METADATA | DST_NOCOUNT);
-
- dst->input = dst_md_discard;
- dst->output = dst_md_discard_out;
-
memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
md_dst->type = type;
}
--
2.30.1
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 1f935e8e72ec28dddb2dc0650b3b6626a293d94b Mon Sep 17 00:00:00 2001
From: David Brazdil <dbrazdil(a)google.com>
Date: Fri, 19 Mar 2021 13:05:41 +0000
Subject: [PATCH] selinux: vsock: Set SID for socket returned by accept()
For AF_VSOCK, accept() currently returns sockets that are unlabelled.
Other socket families derive the child's SID from the SID of the parent
and the SID of the incoming packet. This is typically done as the
connected socket is placed in the queue that accept() removes from.
Reuse the existing 'security_sk_clone' hook to copy the SID from the
parent (server) socket to the child. There is no packet SID in this
case.
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: David Brazdil <dbrazdil(a)google.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/vmw_vsock/af_vsock.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 5546710d8ac1..bc7fb9bf3351 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -755,6 +755,7 @@ static struct sock *__vsock_create(struct net *net,
vsk->buffer_size = psk->buffer_size;
vsk->buffer_min_size = psk->buffer_min_size;
vsk->buffer_max_size = psk->buffer_max_size;
+ security_sk_clone(parent, sk);
} else {
vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN);
vsk->owner = get_current_cred();
--
2.30.1
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From dcc32f4f183ab8479041b23a1525d48233df1d43 Mon Sep 17 00:00:00 2001
From: Jakub Kicinski <kuba(a)kernel.org>
Date: Wed, 17 Mar 2021 09:55:15 -0700
Subject: [PATCH] ipv6: weaken the v4mapped source check
This reverts commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3.
Commit 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped
source address") introduced an input check against v4mapped addresses.
Use of such addresses on the wire is indeed questionable and not
allowed on public Internet. As the commit pointed out
https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02
lists potential issues.
Unfortunately there are applications which use v4mapped addresses,
and breaking them is a clear regression. For example v4mapped
addresses (or any semi-valid addresses, really) may be used
for uni-direction event streams or packet export.
Since the issue which sparked the addition of the check was with
TCP and request_socks in particular push the check down to TCPv6
and DCCP. This restores the ability to receive UDPv6 packets with
v4mapped address as the source.
Keep using the IPSTATS_MIB_INHDRERRORS statistic to minimize the
user-visible changes.
Fixes: 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped source address")
Reported-by: Sunyi Shao <sunyishao(a)fb.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
Acked-by: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Reviewed-by: Eric Dumazet <edumazet(a)google.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/dccp/ipv6.c | 5 +++++
net/ipv6/ip6_input.c | 10 ----------
net/ipv6/tcp_ipv6.c | 5 +++++
net/mptcp/subflow.c | 5 +++++
4 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 1f73603913f5..2be5c69824f9 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -319,6 +319,11 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
return 0; /* discard, don't send a reset here */
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
if (dccp_bad_service_code(sk, service)) {
dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
goto drop;
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index e9d2a4a409aa..80256717868e 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -245,16 +245,6 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev,
if (ipv6_addr_is_multicast(&hdr->saddr))
goto err;
- /* While RFC4291 is not explicit about v4mapped addresses
- * in IPv6 headers, it seems clear linux dual-stack
- * model can not deal properly with these.
- * Security models could be fooled by ::ffff:127.0.0.1 for example.
- *
- * https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02
- */
- if (ipv6_addr_v4mapped(&hdr->saddr))
- goto err;
-
skb->transport_header = skb->network_header + sizeof(*hdr);
IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index bd44ded7e50c..d0f007741e8e 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1175,6 +1175,11 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
goto drop;
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
return tcp_conn_request(&tcp6_request_sock_ops,
&tcp_request_sock_ipv6_ops, sk, skb);
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 3d47d670e665..d17d39ccdf34 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -477,6 +477,11 @@ static int subflow_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
goto drop;
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
return tcp_conn_request(&mptcp_subflow_request_sock_ops,
&subflow_request_sock_ipv6_ops, sk, skb);
--
2.30.1
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 175e476b8cdf2a4de7432583b49c871345e4f8a1 Mon Sep 17 00:00:00 2001
From: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Date: Mon, 8 Mar 2021 14:24:13 +1300
Subject: [PATCH] netfilter: x_tables: Use correct memory barriers.
When a new table value was assigned, it was followed by a write memory
barrier. This ensured that all writes before this point would complete
before any writes after this point. However, to determine whether the
rules are unused, the sequence counter is read. To ensure that all
writes have been done before these reads, a full memory barrier is
needed, not just a write memory barrier. The same argument applies when
incrementing the counter, before the rules are read.
Changing to using smp_mb() instead of smp_wmb() fixes the kernel panic
reported in cc00bcaa5899 (which is still present), while still
maintaining the same speed of replacing tables.
The smb_mb() barriers potentially slow the packet path, however testing
has shown no measurable change in performance on a 4-core MIPS64
platform.
Fixes: 7f5c6d4f665b ("netfilter: get rid of atomic ops in fast path")
Signed-off-by: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Signed-off-by: Pablo Neira Ayuso <pablo(a)netfilter.org>
---
include/linux/netfilter/x_tables.h | 2 +-
net/netfilter/x_tables.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 5deb099d156d..8ec48466410a 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -376,7 +376,7 @@ static inline unsigned int xt_write_recseq_begin(void)
* since addend is most likely 1
*/
__this_cpu_add(xt_recseq.sequence, addend);
- smp_wmb();
+ smp_mb();
return addend;
}
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 7df3aef39c5c..6bd31a7a27fc 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1389,7 +1389,7 @@ xt_replace_table(struct xt_table *table,
table->private = newinfo;
/* make sure all cpus see new ->private value */
- smp_wmb();
+ smp_mb();
/*
* Even though table entries have now been swapped, other CPU's
--
2.30.1
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From a188bb5638d41aa99090ebf2f85d3505ab13fba5 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel(a)iogearbox.net>
Date: Wed, 10 Mar 2021 01:38:10 +0100
Subject: [PATCH] net, bpf: Fix ip6ip6 crash with collect_md populated skbs
I ran into a crash where setting up a ip6ip6 tunnel device which was /not/
set to collect_md mode was receiving collect_md populated skbs for xmit.
The BPF prog was populating the skb via bpf_skb_set_tunnel_key() which is
assigning special metadata dst entry and then redirecting the skb to the
device, taking ip6_tnl_start_xmit() -> ipxip6_tnl_xmit() -> ip6_tnl_xmit()
and in the latter it performs a neigh lookup based on skb_dst(skb) where
we trigger a NULL pointer dereference on dst->ops->neigh_lookup() since
the md_dst_ops do not populate neigh_lookup callback with a fake handler.
Transform the md_dst_ops into generic dst_blackhole_ops that can also be
reused elsewhere when needed, and use them for the metadata dst entries as
callback ops.
Also, remove the dst_md_discard{,_out}() ops and rely on dst_discard{,_out}()
from dst_init() which free the skb the same way modulo the splat. Given we
will be able to recover just fine from there, avoid any potential splats
iff this gets ever triggered in future (or worse, panic on warns when set).
Fixes: f38a9eb1f77b ("dst: Metadata destinations")
Signed-off-by: Daniel Borkmann <daniel(a)iogearbox.net>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/core/dst.c | 31 +++++++++----------------------
1 file changed, 9 insertions(+), 22 deletions(-)
diff --git a/net/core/dst.c b/net/core/dst.c
index 5f6315601776..fb3bcba87744 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -275,37 +275,24 @@ unsigned int dst_blackhole_mtu(const struct dst_entry *dst)
}
EXPORT_SYMBOL_GPL(dst_blackhole_mtu);
-static struct dst_ops md_dst_ops = {
- .family = AF_UNSPEC,
+static struct dst_ops dst_blackhole_ops = {
+ .family = AF_UNSPEC,
+ .neigh_lookup = dst_blackhole_neigh_lookup,
+ .check = dst_blackhole_check,
+ .cow_metrics = dst_blackhole_cow_metrics,
+ .update_pmtu = dst_blackhole_update_pmtu,
+ .redirect = dst_blackhole_redirect,
+ .mtu = dst_blackhole_mtu,
};
-static int dst_md_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
-{
- WARN_ONCE(1, "Attempting to call output on metadata dst\n");
- kfree_skb(skb);
- return 0;
-}
-
-static int dst_md_discard(struct sk_buff *skb)
-{
- WARN_ONCE(1, "Attempting to call input on metadata dst\n");
- kfree_skb(skb);
- return 0;
-}
-
static void __metadata_dst_init(struct metadata_dst *md_dst,
enum metadata_type type, u8 optslen)
-
{
struct dst_entry *dst;
dst = &md_dst->dst;
- dst_init(dst, &md_dst_ops, NULL, 1, DST_OBSOLETE_NONE,
+ dst_init(dst, &dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE,
DST_METADATA | DST_NOCOUNT);
-
- dst->input = dst_md_discard;
- dst->output = dst_md_discard_out;
-
memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
md_dst->type = type;
}
--
2.30.1
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 6ab4c3117aec4e08007d9e971fa4133e1de1082d Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean(a)nxp.com>
Date: Mon, 22 Mar 2021 20:21:08 +0200
Subject: [PATCH] net: bridge: don't notify switchdev for local FDB addresses
As explained in this discussion:
https://lore.kernel.org/netdev/20210117193009.io3nungdwuzmo5f7@skbuf/
the switchdev notifiers for FDB entries managed to have a zero-day bug.
The bridge would not say that this entry is local:
ip link add br0 type bridge
ip link set swp0 master br0
bridge fdb add dev swp0 00:01:02:03:04:05 master local
and the switchdev driver would be more than happy to offload it as a
normal static FDB entry. This is despite the fact that 'local' and
non-'local' entries have completely opposite directions: a local entry
is locally terminated and not forwarded, whereas a static entry is
forwarded and not locally terminated. So, for example, DSA would install
this entry on swp0 instead of installing it on the CPU port as it should.
There is an even sadder part, which is that the 'local' flag is implicit
if 'static' is not specified, meaning that this command produces the
same result of adding a 'local' entry:
bridge fdb add dev swp0 00:01:02:03:04:05 master
I've updated the man pages for 'bridge', and after reading it now, it
should be pretty clear to any user that the commands above were broken
and should have never resulted in the 00:01:02:03:04:05 address being
forwarded (this behavior is coherent with non-switchdev interfaces):
https://patchwork.kernel.org/project/netdevbpf/cover/20210211104502.2081443…
If you're a user reading this and this is what you want, just use:
bridge fdb add dev swp0 00:01:02:03:04:05 master static
Because switchdev should have given drivers the means from day one to
classify FDB entries as local/non-local, but didn't, it means that all
drivers are currently broken. So we can just as well omit the switchdev
notifications for local FDB entries, which is exactly what this patch
does to close the bug in stable trees. For further development work
where drivers might want to trap the local FDB entries to the host, we
can add a 'bool is_local' to br_switchdev_fdb_call_notifiers(), and
selectively make drivers act upon that bit, while all the others ignore
those entries if the 'is_local' bit is set.
Fixes: 6b26b51b1d13 ("net: bridge: Add support for notifying devices about FDB add/del")
Signed-off-by: Vladimir Oltean <vladimir.oltean(a)nxp.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/bridge/br_switchdev.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index b89503832fcc..1e24d9a2c9a7 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -128,6 +128,8 @@ br_switchdev_fdb_notify(const struct net_bridge_fdb_entry *fdb, int type)
{
if (!fdb->dst)
return;
+ if (test_bit(BR_FDB_LOCAL, &fdb->flags))
+ return;
switch (type) {
case RTM_DELNEIGH:
--
2.30.1
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 1f935e8e72ec28dddb2dc0650b3b6626a293d94b Mon Sep 17 00:00:00 2001
From: David Brazdil <dbrazdil(a)google.com>
Date: Fri, 19 Mar 2021 13:05:41 +0000
Subject: [PATCH] selinux: vsock: Set SID for socket returned by accept()
For AF_VSOCK, accept() currently returns sockets that are unlabelled.
Other socket families derive the child's SID from the SID of the parent
and the SID of the incoming packet. This is typically done as the
connected socket is placed in the queue that accept() removes from.
Reuse the existing 'security_sk_clone' hook to copy the SID from the
parent (server) socket to the child. There is no packet SID in this
case.
Fixes: d021c344051a ("VSOCK: Introduce VM Sockets")
Signed-off-by: David Brazdil <dbrazdil(a)google.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/vmw_vsock/af_vsock.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 5546710d8ac1..bc7fb9bf3351 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -755,6 +755,7 @@ static struct sock *__vsock_create(struct net *net,
vsk->buffer_size = psk->buffer_size;
vsk->buffer_min_size = psk->buffer_min_size;
vsk->buffer_max_size = psk->buffer_max_size;
+ security_sk_clone(parent, sk);
} else {
vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN);
vsk->owner = get_current_cred();
--
2.30.1
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From dcc32f4f183ab8479041b23a1525d48233df1d43 Mon Sep 17 00:00:00 2001
From: Jakub Kicinski <kuba(a)kernel.org>
Date: Wed, 17 Mar 2021 09:55:15 -0700
Subject: [PATCH] ipv6: weaken the v4mapped source check
This reverts commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3.
Commit 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped
source address") introduced an input check against v4mapped addresses.
Use of such addresses on the wire is indeed questionable and not
allowed on public Internet. As the commit pointed out
https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02
lists potential issues.
Unfortunately there are applications which use v4mapped addresses,
and breaking them is a clear regression. For example v4mapped
addresses (or any semi-valid addresses, really) may be used
for uni-direction event streams or packet export.
Since the issue which sparked the addition of the check was with
TCP and request_socks in particular push the check down to TCPv6
and DCCP. This restores the ability to receive UDPv6 packets with
v4mapped address as the source.
Keep using the IPSTATS_MIB_INHDRERRORS statistic to minimize the
user-visible changes.
Fixes: 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped source address")
Reported-by: Sunyi Shao <sunyishao(a)fb.com>
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
Acked-by: Mat Martineau <mathew.j.martineau(a)linux.intel.com>
Reviewed-by: Eric Dumazet <edumazet(a)google.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
---
net/dccp/ipv6.c | 5 +++++
net/ipv6/ip6_input.c | 10 ----------
net/ipv6/tcp_ipv6.c | 5 +++++
net/mptcp/subflow.c | 5 +++++
4 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 1f73603913f5..2be5c69824f9 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -319,6 +319,11 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
return 0; /* discard, don't send a reset here */
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
if (dccp_bad_service_code(sk, service)) {
dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
goto drop;
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index e9d2a4a409aa..80256717868e 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -245,16 +245,6 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev,
if (ipv6_addr_is_multicast(&hdr->saddr))
goto err;
- /* While RFC4291 is not explicit about v4mapped addresses
- * in IPv6 headers, it seems clear linux dual-stack
- * model can not deal properly with these.
- * Security models could be fooled by ::ffff:127.0.0.1 for example.
- *
- * https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02
- */
- if (ipv6_addr_v4mapped(&hdr->saddr))
- goto err;
-
skb->transport_header = skb->network_header + sizeof(*hdr);
IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index bd44ded7e50c..d0f007741e8e 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1175,6 +1175,11 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
goto drop;
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
return tcp_conn_request(&tcp6_request_sock_ops,
&tcp_request_sock_ipv6_ops, sk, skb);
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 3d47d670e665..d17d39ccdf34 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -477,6 +477,11 @@ static int subflow_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!ipv6_unicast_destination(skb))
goto drop;
+ if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
+ __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
+ return 0;
+ }
+
return tcp_conn_request(&mptcp_subflow_request_sock_ops,
&subflow_request_sock_ipv6_ops, sk, skb);
--
2.30.1
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From 175e476b8cdf2a4de7432583b49c871345e4f8a1 Mon Sep 17 00:00:00 2001
From: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Date: Mon, 8 Mar 2021 14:24:13 +1300
Subject: [PATCH] netfilter: x_tables: Use correct memory barriers.
When a new table value was assigned, it was followed by a write memory
barrier. This ensured that all writes before this point would complete
before any writes after this point. However, to determine whether the
rules are unused, the sequence counter is read. To ensure that all
writes have been done before these reads, a full memory barrier is
needed, not just a write memory barrier. The same argument applies when
incrementing the counter, before the rules are read.
Changing to using smp_mb() instead of smp_wmb() fixes the kernel panic
reported in cc00bcaa5899 (which is still present), while still
maintaining the same speed of replacing tables.
The smb_mb() barriers potentially slow the packet path, however testing
has shown no measurable change in performance on a 4-core MIPS64
platform.
Fixes: 7f5c6d4f665b ("netfilter: get rid of atomic ops in fast path")
Signed-off-by: Mark Tomlinson <mark.tomlinson(a)alliedtelesis.co.nz>
Signed-off-by: Pablo Neira Ayuso <pablo(a)netfilter.org>
---
include/linux/netfilter/x_tables.h | 2 +-
net/netfilter/x_tables.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 5deb099d156d..8ec48466410a 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -376,7 +376,7 @@ static inline unsigned int xt_write_recseq_begin(void)
* since addend is most likely 1
*/
__this_cpu_add(xt_recseq.sequence, addend);
- smp_wmb();
+ smp_mb();
return addend;
}
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 7df3aef39c5c..6bd31a7a27fc 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1389,7 +1389,7 @@ xt_replace_table(struct xt_table *table,
table->private = newinfo;
/* make sure all cpus see new ->private value */
- smp_wmb();
+ smp_mb();
/*
* Even though table entries have now been swapped, other CPU's
--
2.30.1