linux-toradex.git/net/ipv6, branch v4.9.37

ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets

2017-07-05T12:40:27+00:00

[ Upstream commit 0e9a709560dbcfbace8bf4019dc5298619235891 ]

This fix addresses two problems in the way the DSCP field is formulated
 on the encapsulating header of IPv6 tunnels.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195661

1) The IPv6 tunneling code was manipulating the DSCP field of the
 encapsulating packet using the 32b flowlabel. Since the flowlabel is
 only the lower 20b it was incorrect to assume that the upper 12b
 containing the DSCP and ECN fields would remain intact when formulating
 the encapsulating header. This fix handles the 'inherit' and
 'fixed-value' DSCP cases explicitly using the extant dsfield u8 variable.

2) The use of INET_ECN_encapsulate(0, dsfield) in ip6_tnl_xmit was
 incorrect and resulted in the DSCP value always being set to 0.

Commit 90427ef5d2a4 ("ipv6: fix flow labels when the traffic class
 is non-0") caused the regression by masking out the flowlabel
 which exposed the incorrect handling of the DSCP portion of the
 flowlabel in ip6_tunnel and ip6_gre.

Fixes: 90427ef5d2a4 ("ipv6: fix flow labels when the traffic class is non-0")
Signed-off-by: Peter Dawson 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ip6_tunnel: must reload ipv6h in ip6ip6_tnl_xmit()

2017-07-05T12:40:23+00:00

[ Upstream commit 21b995a9cb093fff33ec91d7cb3822b882a90a1e ]

Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull(),
we must reload any pointer that was related to skb->head
(or skb->data), or risk use after free.

Fixes: c12b395a4664 ("gre: Support GRE over IPv6")
Signed-off-by: Eric Dumazet 
Cc: Dmitry Kozlov 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ipv6: Do not leak throw route references

2017-07-05T12:40:16+00:00

[ Upstream commit 07f615574f8ac499875b21c1142f26308234a92c ]

While commit 73ba57bfae4a ("ipv6: fix backtracking for throw routes")
does good job on error propagation to the fib_rules_lookup()
in fib rules core framework that also corrects throw routes
handling, it does not solve route reference leakage problem
happened when we return -EAGAIN to the fib_rules_lookup()
and leave routing table entry referenced in arg->result.

If rule with matched throw route isn't last matched in the
list we overwrite arg->result losing reference on throw
route stored previously forever.

We also partially revert commit ab997ad40839 ("ipv6: fix the
incorrect return value of throw route") since we never return
routing table entry with dst.error == -EAGAIN when
CONFIG_IPV6_MULTIPLE_TABLES is on. Also there is no point
to check for RTF_REJECT flag since it is always set throw
route.

Fixes: 73ba57bfae4a ("ipv6: fix backtracking for throw routes")
Signed-off-by: Serhey Popovych 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix calling in6_ifa_hold incorrectly for dad work

2017-07-05T12:40:15+00:00

[ Upstream commit f8a894b218138888542a5058d0e902378fd0d4ec ]

Now when starting the dad work in addrconf_mod_dad_work, if the dad work
is idle and queued, it needs to hold ifa.

The problem is there's one gap in [1], during which if the pending dad work
is removed elsewhere. It will miss to hold ifa, but the dad word is still
idea and queue.

        if (!delayed_work_pending(&ifp->dad_work))
                in6_ifa_hold(ifp);
                    <--------------[1]
        mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);

An use-after-free issue can be caused by this.

Chen Wei found this issue when WARN_ON(!hlist_unhashed(&ifp->addr_lst)) in
net6_ifa_finish_destroy was hit because of it.

As Hannes' suggestion, this patch is to fix it by holding ifa first in
addrconf_mod_dad_work, then calling mod_delayed_work and putting ifa if
the dad_work is already in queue.

Note that this patch did not choose to fix it with:

  if (!mod_delayed_work(delay))
          in6_ifa_hold(ifp);

As with it, when delay == 0, dad_work would be scheduled immediately, all
addrconf_mod_dad_work(0) callings had to be moved under ifp->lock.

Reported-by: Wei Chen 
Suggested-by: Hannes Frederic Sowa 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

proc: snmp6: Use correct type in memset

2017-07-05T12:40:15+00:00

[ Upstream commit 3500cd73dff48f28f4ba80c171c4c80034d40f76 ]

Reading /proc/net/snmp6 yields bogus values on 32 bit kernels.
Use "u64" instead of "unsigned long" in sizeof().

Fixes: 4a4857b1c81e ("proc: Reduce cache miss in snmp6_seq_show")
Signed-off-by: Christian Perle 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: release dst on error in ip6_dst_lookup_tail

2017-07-05T12:40:13+00:00

commit 00ea1ceebe0d9f2dc1cc2b7bd575a00100c27869 upstream.

If ip6_dst_lookup_tail has acquired a dst and fails the IPv4-mapped
check, release the dst before returning an error.

Fixes: ec5e3b0a1d41 ("ipv6: Inhibit IPv4-mapped src address on the wire.")
Signed-off-by: Willem de Bruijn 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

ila_xlat: add missing hash secret initialization

2017-06-24T05:11:12+00:00

commit 0db47e3d323411beeb6ea97f2c4d19395c91fd8b upstream.

While discussing the possible merits of clang warning about unused initialized
functions, I found one function that was clearly meant to be called but
never actually is.

__ila_hash_secret_init() initializes the hash value for the ila locator,
apparently this is intended to prevent hash collision attacks, but this ends
up being a read-only zero constant since there is no caller. I could find
no indication of why it was never called, the earliest patch submission
for the module already was like this. If my interpretation is right, we
certainly want to backport the patch to stable kernels as well.

I considered adding it to the ila_xlat_init callback, but for best effect
the random data is read as late as possible, just before it is first used.
The underlying net_get_random_once() is already highly optimized to avoid
overhead when called frequently.

Fixes: 7f00feaf1076 ("ila: Add generic ILA translation facility")
Link: https://www.spinics.net/lists/kernel/msg2527243.html
Signed-off-by: Arnd Bergmann 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Fix IPv6 packet loss in scenarios involving roaming + snooping switches

2017-06-17T04:41:51+00:00

[ Upstream commit a088d1d73a4bcfd7bc482f8d08375b9b665dc3e5 ]

When for instance a mobile Linux device roams from one access point to
another with both APs sharing the same broadcast domain and a
multicast snooping switch in between:

1)    (c) <~~~> (AP1) <--[SSW]--> (AP2)

2)              (AP1) <--[SSW]--> (AP2) <~~~> (c)

Then currently IPv6 multicast packets will get lost for (c) until an
MLD Querier sends its next query message. The packet loss occurs
because upon roaming the Linux host so far stayed silent regarding
MLD and the snooping switch will therefore be unaware of the
multicast topology change for a while.

This patch fixes this by always resending MLD reports when an interface
change happens, for instance from NO-CARRIER to CARRIER state.

Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ipv6: addrconf: fix generation of new temporary addresses

2017-06-17T04:41:51+00:00

[ Upstream commit a11a7f71cac209c7c9cca66eb506e1ebb033a3b3 ]

Under some circumstances it is possible that no new temporary addresses
will be generated.

For instance, addrconf_prefix_rcv_add_addr() indirectly calls
ipv6_create_tempaddr(), which creates a tentative temporary address and
starts dad. Next, addrconf_prefix_rcv_add_addr() indirectly calls
addrconf_verify_rtnl(). Now, assume that the previously created temporary
address has the least preferred lifetime among all existing addresses and
is still tentative (that is, dad is still running). Hence, the next run of
addrconf_verify_rtnl() is performed when the preferred lifetime of the
temporary address ends. If dad succeeds before the next run, the temporary
address becomes deprecated during the next run, but no new temporary
address is generated.

In order to fix this, schedule the next addrconf_verify_rtnl() run slightly
before the temporary address becomes deprecated, if dad succeeded.

Signed-off-by: Marcus Huewe 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ipv6: Inhibit IPv4-mapped src address on the wire.

2017-06-17T04:41:49+00:00

[ Upstream commit ec5e3b0a1d41fbda0cc33a45bc9e54e91d9d12c7 ]

This patch adds a check for the problematic case of an IPv4-mapped IPv6
source address and a destination address that is neither an IPv4-mapped
IPv6 address nor in6addr_any, and returns an appropriate error. The
check in done before returning from looking up the route.

Signed-off-by: Jonathan T. Leighton 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman