linux-stable.git/net, branch v4.9.155

l2tp: fix reading optional fields of L2TPv3

2019-02-06T16:33:27+00:00

[ Upstream commit 4522a70db7aa5e77526a4079628578599821b193 ]

Use pskb_may_pull() to make sure the optional fields are in skb linear
parts, so we can safely read them later.

It's easy to reproduce the issue with a net driver that supports paged
skb data. Just create a L2TPv3 over IP tunnel and then generates some
network traffic.
Once reproduced, rx err in /sys/kernel/debug/l2tp/tunnels will increase.

Changes in v4:
1. s/l2tp_v3_pull_opt/l2tp_v3_ensure_opt_in_linear/
2. s/tunnel->version != L2TP_HDR_VER_2/tunnel->version == L2TP_HDR_VER_3/
3. Add 'Fixes' in commit messages.

Changes in v3:
1. To keep consistency, move the code out of l2tp_recv_common.
2. Use "net" instead of "net-next", since this is a bug fix.

Changes in v2:
1. Only fix L2TPv3 to make code simple.
   To fix both L2TPv3 and L2TPv2, we'd better refactor l2tp_recv_common.
   It's complicated to do so.
2. Reloading pointers after pskb_may_pull

Fixes: f7faffa3ff8e ("l2tp: Add L2TPv3 protocol support")
Fixes: 0d76751fad77 ("l2tp: Add L2TPv3 IP encapsulation (no UDP) support")
Fixes: a32e0eec7042 ("l2tp: introduce L2TPv3 IP encapsulation support for IPv6")
Signed-off-by: Jacob Wen 
Acked-by: Guillaume Nault 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

l2tp: remove l2specific_len dependency in l2tp_core

2019-02-06T16:33:27+00:00

commit 62e7b6a57c7b9bf3c6fd99418eeec05b08a85c38 upstream.

Remove l2specific_len dependency while building l2tpv3 header or
parsing the received frame since default L2-Specific Sublayer is
always four bytes long and we don't need to rely on a user supplied
value.
Moreover in l2tp netlink code there are no sanity checks to
enforce the relation between l2specific_len and l2specific_type,
so sending a malformed netlink message is possible to set
l2specific_type to L2TP_L2SPECTYPE_DEFAULT (or even
L2TP_L2SPECTYPE_NONE) and set l2specific_len to a value greater than
4 leaking memory on the wire and sending corrupted frames.

Reviewed-by: Guillaume Nault 
Tested-by: Guillaume Nault 
Signed-off-by: Lorenzo Bianconi 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net/rose: fix NULL ax25_cb kernel panic

2019-02-06T16:33:27+00:00

[ Upstream commit b0cf029234f9b18e10703ba5147f0389c382bccc ]

When an internally generated frame is handled by rose_xmit(),
rose_route_frame() is called:

        if (!rose_route_frame(skb, NULL)) {
                dev_kfree_skb(skb);
                stats->tx_errors++;
                return NETDEV_TX_OK;
        }

We have the same code sequence in Net/Rom where an internally generated
frame is handled by nr_xmit() calling nr_route_frame(skb, NULL).
However, in this function NULL argument is tested while it is not in
rose_route_frame().
Then kernel panic occurs later on when calling ax25cmp() with a NULL
ax25_cb argument as reported many times and recently with syzbot.

We need to test if ax25 is NULL before using it.

Testing:
Built kernel with CONFIG_ROSE=y.

Signed-off-by: Bernard Pidoux 
Acked-by: Dmitry Vyukov 
Reported-by: syzbot+1a2c456a1ea08fa5b5f7@syzkaller.appspotmail.com
Cc: "David S. Miller" 
Cc: Ralf Baechle 
Cc: Bernard Pidoux 
Cc: linux-hams@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netrom: switch to sock timer API

2019-02-06T16:33:27+00:00

[ Upstream commit 63346650c1a94a92be61a57416ac88c0a47c4327 ]

sk_reset_timer() and sk_stop_timer() properly handle
sock refcnt for timer function. Switching to them
could fix a refcounting bug reported by syzbot.

Reported-and-tested-by: syzbot+defa700d16f1bd1b9a05@syzkaller.appspotmail.com
Cc: Ralf Baechle 
Cc: linux-hams@vger.kernel.org
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

l2tp: copy 4 more bytes to linear part if necessary

2019-02-06T16:33:26+00:00

[ Upstream commit 91c524708de6207f59dd3512518d8a1c7b434ee3 ]

The size of L2TPv2 header with all optional fields is 14 bytes.
l2tp_udp_recv_core only moves 10 bytes to the linear part of a
skb. This may lead to l2tp_recv_common read data outside of a skb.

This patch make sure that there is at least 14 bytes in the linear
part of a skb to meet the maximum need of l2tp_udp_recv_core and
l2tp_recv_common. The minimum size of both PPP HDLC-like frame and
Ethernet frame is larger than 14 bytes, so we are safe to do so.

Also remove L2TP_HDR_SIZE_NOSEQ, it is unused now.

Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Suggested-by: Guillaume Nault 
Signed-off-by: Jacob Wen 
Acked-by: Guillaume Nault 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Consider sk_bound_dev_if when binding a socket to an address

2019-02-06T16:33:26+00:00

[ Upstream commit c5ee066333ebc322a24a00a743ed941a0c68617e ]

IPv6 does not consider if the socket is bound to a device when binding
to an address. The result is that a socket can be bound to eth0 and then
bound to the address of eth1. If the device is a VRF, the result is that
a socket can only be bound to an address in the default VRF.

Resolve by considering the device if sk_bound_dev_if is set.

This problem exists from the beginning of git history.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Fix "net: ipv4: do not handle duplicate fragments as overlapping"

2019-02-06T16:33:26+00:00

ade446403bfb ("net: ipv4: do not handle duplicate fragments as
overlapping") was backported to many stable trees, but it had a problem
that was "accidentally" fixed by the upstream commit 0ff89efb5246 ("ip:
fail fast on IP defrag errors")

This is the fixup for that problem as we do not want the larger patch in
the older stable trees.

Fixes: ade446403bfb ("net: ipv4: do not handle duplicate fragments as overlapping")
Reported-by: Ivan Babrou 
Reported-by: Eric Dumazet 
Signed-off-by: Greg Kroah-Hartman

can: bcm: check timer values before ktime conversion

2019-01-31T07:12:36+00:00

commit 93171ba6f1deffd82f381d36cb13177872d023f6 upstream.

Kyungtae Kim detected a potential integer overflow in bcm_[rx|tx]_setup()
when the conversion into ktime multiplies the given value with NSEC_PER_USEC
(1000).

Reference: https://marc.info/?l=linux-can&m=154732118819828&w=2

Add a check for the given tv_usec, so that the value stays below one second.
Additionally limit the tv_sec value to a reasonable value for CAN related
use-cases of 400 days and ensure all values to be positive.

Reported-by: Kyungtae Kim 
Tested-by: Oliver Hartkopp 
Signed-off-by: Oliver Hartkopp 
Cc: linux-stable  # >= 2.6.26
Tested-by: Kyungtae Kim 
Acked-by: Andre Naujoks 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

ipfrag: really prevent allocation on netns exit

2019-01-31T07:12:33+00:00

[ Upstream commit f6f2a4a2eb92bc73671204198bb2f8ab53ff59fb ]

Setting the low threshold to 0 has no effect on frags allocation,
we need to clear high_thresh instead.

The code was pre-existent to commit 648700f76b03 ("inet: frags:
use rhashtables for reassembly units"), but before the above,
such assignment had a different role: prevent concurrent eviction
from the worker and the netns cleanup helper.

Fixes: 648700f76b03 ("inet: frags: use rhashtables for reassembly units")
Signed-off-by: Paolo Abeni 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net_sched: refetch skb protocol for each filter

2019-01-31T07:12:33+00:00

[ Upstream commit cd0c4e70fc0ccfa705cdf55efb27519ce9337a26 ]

Martin reported a set of filters don't work after changing
from reclassify to continue. Looking into the code, it
looks like skb protocol is not always fetched for each
iteration of the filters. But, as demonstrated by Martin,
TC actions could modify skb->protocol, for example act_vlan,
this means we have to refetch skb protocol in each iteration,
rather than using the one we fetch in the beginning of the loop.

This bug is _not_ introduced by commit 3b3ae880266d
("net: sched: consolidate tc_classify{,_compat}"), technically,
if act_vlan is the only action that modifies skb protocol, then
it is commit c7e2b9689ef8 ("sched: introduce vlan action") which
introduced this bug.

Reported-by: Martin Olsson 
Cc: Jamal Hadi Salim 
Cc: Jiri Pirko 
Signed-off-by: Cong Wang 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman