linux-toradex.git/net/ipv6, branch v3.10.24

ipv6: fix possible seqlock deadlock in ip6_finish_output2

2013-12-08T15:29:26+00:00

[ Upstream commit 7f88c6b23afbd31545c676dea77ba9593a1a14bf ]

IPv6 stats are 64 bits and thus are protected with a seqlock. By not
disabling bottom-half we could deadlock here if we don't disable bh and
a softirq reentrantly updates the same mib.

Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netfilter: push reasm skb through instead of original frag skbs

2013-12-08T15:29:25+00:00

[ Upstream commit 6aafeef03b9d9ecf255f3a80ed85ee070260e1ae ]

Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:


On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT

and on HOSTB you do:
ping6 HOSTA -s2000    (MTU is 1500)

Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)


As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.

Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.

Signed-off-by: Jiri Pirko 
Acked-by: Julian Anastasov 
Signed-off-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip6_output: fragment outgoing reassembled skb properly

2013-12-08T15:29:25+00:00

[ Upstream commit 9037c3579a277f3a23ba476664629fda8c35f7c4 ]

If reassembled packet would fit into outdev MTU, it is not fragmented
according the original frag size and it is send as single big packet.

The second case is if skb is gso. In that case fragmentation does not happen
according to the original frag size.

This patch fixes these.

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

ipv6: fix leaking uninitialized port number of offender sockaddr

2013-12-08T15:29:25+00:00

[ Upstream commit 1fa4c710b6fe7b0aac9907240291b6fe6aafc3b8 ]

Offenders don't have port numbers, so set it to 0.

Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

inet: fix addr_len/msg->msg_namelen assignment in recv_error and rxpmtu functions

2013-12-08T15:29:25+00:00

[ Upstream commit 85fbaa75037d0b6b786ff18658ddf0b4014ce2a4 ]

Commit bceaa90240b6019ed73b49965eac7d167610be69 ("inet: prevent leakage
of uninitialized memory to user in recv syscalls") conditionally updated
addr_len if the msg_name is written to. The recv_error and rxpmtu
functions relied on the recvmsg functions to set up addr_len before.

As this does not happen any more we have to pass addr_len to those
functions as well and set it to the size of the corresponding sockaddr
length.

This broke traceroute and such.

Fixes: bceaa90240b6 ("inet: prevent leakage of uninitialized memory to user in recv syscalls")
Reported-by: Brad Spengler 
Reported-by: Tom Labanowski
Cc: mpb 
Cc: David S. Miller 
Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

inet: prevent leakage of uninitialized memory to user in recv syscalls

2013-12-08T15:29:25+00:00

[ Upstream commit bceaa90240b6019ed73b49965eac7d167610be69 ]

Only update *addr_len when we actually fill in sockaddr, otherwise we
can return uninitialized memory from the stack to the caller in the
recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL)
checks because we only get called with a valid addr_len pointer either
from sock_common_recvmsg or inet_recvmsg.

If a blocking read waits on a socket which is concurrently shut down we
now return zero and set msg_msgnamelen to 0.

Reported-by: mpb 
Suggested-by: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: protect for_each_sk_fl_rcu in mem_check with rcu_read_lock_bh

2013-12-08T15:29:24+00:00

[ Upstream commit f8c31c8f80dd882f7eb49276989a4078d33d67a7 ]

Fixes a suspicious rcu derference warning.

Cc: Florent Fourcot 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: use rt6_get_dflt_router to get default router in rt6_route_rcv

2013-12-08T15:29:24+00:00

[ Upstream commit f104a567e673f382b09542a8dc3500aa689957b4 ]

As the rfc 4191 said, the Router Preference and Lifetime values in a
::/0 Route Information Option should override the preference and lifetime
values in the Router Advertisement header. But when the kernel deals with
a ::/0 Route Information Option, the rt6_get_route_info() always return
NULL, that means that overriding will not happen, because those default
routers were added without flag RTF_ROUTEINFO in rt6_add_dflt_router().

In order to deal with that condition, we should call rt6_get_dflt_router
when the prefix length is 0.

Signed-off-by: Duan Jiong 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix headroom calculation in udp6_ufo_fragment

2013-12-08T15:29:23+00:00

[ Upstream commit 0e033e04c2678dbbe74a46b23fffb7bb918c288e ]

Commit 1e2bd517c108816220f262d7954b697af03b5f9c ("udp6: Fix udp
fragmentation for tunnel traffic.") changed the calculation if
there is enough space to include a fragment header in the skb from a
skb->mac_header dervived one to skb_headroom. Because we already peeled
off the skb to transport_header this is wrong. Change this back to check
if we have enough room before the mac_header.

This fixes a panic Saran Neti reported. He used the tbf scheduler which
skb_gso_segments the skb. The offsets get negative and we panic in memcpy
because the skb was erroneously not expanded at the head.

Reported-by: Saran Neti 
Cc: Pravin B Shelar 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: ip6_dst_check needs to check for expired dst_entries

2013-11-20T20:27:46+00:00

[ Upstream commit e3bc10bd95d7fcc3f2ac690c6ff22833ea6781d6 ]

On receiving a packet too big icmp error we check if our current cached
dst_entry in the socket is still valid. This validation check did not
care about the expiration of the (cached) route.

The error path I traced down:
The socket receives a packet too big mtu notification. It still has a
valid dst_entry and thus issues the ip6_rt_pmtu_update on this dst_entry,
setting RTF_EXPIRE and updates the dst.expiration value (which could
fail because of not up-to-date expiration values, see previous patch).

In some seldom cases we race with a) the ip6_fib gc or b) another routing
lookup which would result in a recreation of the cached rt6_info from its
parent non-cached rt6_info. While copying the rt6_info we reinitialize the
metrics store by copying it over from the parent thus invalidating the
just installed pmtu update (both dsts use the same key to the inetpeer
storage). The dst_entry with the just invalidated metrics data would
just get its RTF_EXPIRES flag cleared and would continue to stay valid
for the socket.

We should have not issued the pmtu update on the already expired dst_entry
in the first placed. By checking the expiration on the dst entry and
doing a relookup in case it is out of date we close the race because
we would install a new rt6_info into the fib before we issue the pmtu
update, thus closing this race.

Not reliably updating the dst.expire value was fixed by the patch "ipv6:
reset dst.expires value when clearing expire flag".

Reported-by: Steinar H. Gunderson 
Reported-by: Valentijn Sessink 
Cc: YOSHIFUJI Hideaki 
Signed-off-by: Hannes Frederic Sowa 
Reviewed-by: Eric Dumazet 
Tested-by: Valentijn Sessink 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman