linux-stable.git/net/ipv4, branch v3.16.67

ipv4: fix a race in update_or_create_fnhe()

2019-05-11T14:22:48+00:00

commit caa415270c732505240bb60171c44a7838c555e8 upstream.

nh_exceptions is effectively used under rcu, but lacks proper
barriers. Between kzalloc() and setting of nh->nh_exceptions(),
we need a proper memory barrier.

Signed-off-by: Eric Dumazet 
Fixes: 4895c771c7f00 ("ipv4: Add FIB nexthop exceptions.")
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

inet: update the IP ID generation algorithm to higher standards.

2019-05-11T14:22:47+00:00

Commit 355b98553789 ("netns: provide pure entropy for net_hash_mix()")
makes net_hash_mix() return a true 32 bits of entropy.  When used in the
IP ID generation algorithm, this has the effect of extending the IP ID
generation key from 32 bits to 64 bits.

However, net_hash_mix() is only used for IP ID generation starting with
kernel version 4.1.  Therefore, earlier kernels remain with 32-bit key
no matter what the net_hash_mix() return value is.

This change addresses the issue by explicitly extending the key to 64
bits for kernels older than 4.1.

Signed-off-by: Amit Klein 
Signed-off-by: Ben Hutchings

netlabel: fix out-of-bounds memory accesses

2019-05-02T20:42:01+00:00

commit 5578de4834fe0f2a34fedc7374be691443396d1f upstream.

There are two array out-of-bounds memory accesses, one in
cipso_v4_map_lvl_valid(), the other in netlbl_bitmap_walk().  Both
errors are embarassingly simple, and the fixes are straightforward.

As a FYI for anyone backporting this patch to kernels prior to v4.8,
you'll want to apply the netlbl_bitmap_walk() patch to
cipso_v4_bitmap_walk() as netlbl_bitmap_walk() doesn't exist before
Linux v4.8.

Reported-by: Jann Horn 
Fixes: 446fda4f2682 ("[NetLabel]: CIPSOv4 engine")
Fixes: 3faa8f982f95 ("netlabel: Move bitmap manipulation functions to the NetLabel core.")
Signed-off-by: Paul Moore 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.16 following Paul's hint]
Signed-off-by: Ben Hutchings

net/ipv4: defensive cipso option parsing

2019-02-11T17:53:21+00:00

commit 076ed3da0c9b2f88d9157dbe7044a45641ae369e upstream.

commit 40413955ee26 ("Cipso: cipso_v4_optptr enter infinite loop") fixed
a possible infinite loop in the IP option parsing of CIPSO. The fix
assumes that ip_options_compile filtered out all zero length options and
that no other one-byte options beside IPOPT_END and IPOPT_NOOP exist.
While this assumption currently holds true, add explicit checks for zero
length and invalid length options to be safe for the future. Even though
ip_options_compile should have validated the options, the introduction of
new one-byte options can still confuse this code without the additional
checks.

Signed-off-by: Stefan Nuernberger 
Cc: David Woodhouse 
Cc: Simon Veith 
Acked-by: Paul Moore 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

Cipso: cipso_v4_optptr enter infinite loop

2019-02-11T17:53:21+00:00

commit 40413955ee265a5e42f710940ec78f5450d49149 upstream.

in for(),if((optlen > 0) && (optptr[1] == 0)), enter infinite loop.

Test: receive a packet which the ip length > 20 and the first byte of ip option is 0, produce this issue

Signed-off-by: yujuan.qi 
Acked-by: Paul Moore 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

cipso: don't use IPCB() to locate the CIPSO IP option

2019-02-11T17:53:21+00:00

commit 04f81f0154e4bf002be6f4d85668ce1257efa4d9 upstream.

Using the IPCB() macro to get the IPv4 options is convenient, but
unfortunately NetLabel often needs to examine the CIPSO option outside
of the scope of the IP layer in the stack.  While historically IPCB()
worked above the IP layer, due to the inclusion of the inet_skb_param
struct at the head of the {tcp,udp}_skb_cb structs, recent commit
971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
reordered the tcp_skb_cb struct and invalidated this IPCB() trick.

This patch fixes the problem by creating a new function,
cipso_v4_optptr(), which locates the CIPSO option inside the IP header
without calling IPCB().  Unfortunately, this isn't as fast as a simple
lookup so some additional tweaks were made to limit the use of this
new function.

Reported-by: Casey Schaufler 
Signed-off-by: Paul Moore 
Tested-by: Casey Schaufler 
Signed-off-by: Ben Hutchings

net: ipv4: update fnhe_pmtu when first hop's MTU changes

2018-12-16T22:09:40+00:00

commit af7d6cce53694a88d6a1bb60c9a239a6a5144459 upstream.

Since commit 5aad1de5ea2c ("ipv4: use separate genid for next hop
exceptions"), exceptions get deprecated separately from cached
routes. In particular, administrative changes don't clear PMTU anymore.

As Stefano described in commit e9fa1495d738 ("ipv6: Reflect MTU changes
on PMTU of exceptions for MTU-less routes"), the PMTU discovered before
the local MTU change can become stale:
 - if the local MTU is now lower than the PMTU, that PMTU is now
   incorrect
 - if the local MTU was the lowest value in the path, and is increased,
   we might discover a higher PMTU

Similarly to what commit e9fa1495d738 did for IPv6, update PMTU in those
cases.

If the exception was locked, the discovered PMTU was smaller than the
minimal accepted PMTU. In that case, if the new local MTU is smaller
than the current PMTU, let PMTU discovery figure out if locking of the
exception is still needed.

To do this, we need to know the old link MTU in the NETDEV_CHANGEMTU
notifier. By the time the notifier is called, dev->mtu has been
changed. This patch adds the old MTU as additional information in the
notifier structure, and a new call_netdevice_notifiers_u32() function.

Fixes: 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions")
Signed-off-by: Sabrina Dubroca 
Reviewed-by: Stefano Brivio 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.16:
 - Pass net_device argument to call_netdevice_notifiers_info()
 - Adjust context]
Signed-off-by: Ben Hutchings

ip_tunnel: be careful when accessing the inner header

2018-12-16T22:09:25+00:00

commit ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2 upstream.

Cong noted that we need the same checks introduced by commit 76c0ddd8c3a6
("ip6_tunnel: be careful when accessing the inner header")
even for ipv4 tunnels.

Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Suggested-by: Cong Wang 
Signed-off-by: Paolo Abeni 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

igmp: fix incorrect unsolicit report count after link down and up

2018-12-16T22:08:59+00:00

commit ff06525fcb8ae3c302ac1319bf6c07c026dea964 upstream.

After link down and up, i.e. when call ip_mc_up(), we doesn't init
im->unsolicit_count. So after igmp_timer_expire(), we will not start
timer again and only send one unsolicit report at last.

Fix it by initializing im->unsolicit_count in igmp_group_added(), so
we can respect igmp robustness value.

Fixes: 24803f38a5c0b ("igmp: do not remove igmp souce list info when set link down")
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
[bwh: Backported to 3.16:
 - Keep using constant IGMP_Unsolicited_Report_Count
 - Adjust context]
Signed-off-by: Ben Hutchings

igmp: fix incorrect unsolicit report count when join group

2018-12-16T22:08:59+00:00

commit 4fb7253e4f9a8f06a986a3b317e2f79d9b43d552 upstream.

We should not start timer if im->unsolicit_count equal to 0 after decrease.
Or we will send one more unsolicit report message. i.e. 3 instead of 2 by
default.

Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2")
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings