linux-stable.git/net/ipv6, branch v4.4.115

ipv6: ip6_make_skb() needs to clear cork.base.dst

2018-01-31T11:06:13+00:00

[ Upstream commit 95ef498d977bf44ac094778fd448b98af158a3e6 ]

In my last patch, I missed fact that cork.base.dst was not initialized
in ip6_make_skb() :

If ip6_setup_cork() returns an error, we might attempt a dst_release()
on some random pointer.

Fixes: 862c03ee1deb ("ipv6: fix possible mem leaks in ipv6_make_skb()")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix udpv6 sendmsg crash caused by too small MTU

2018-01-31T11:06:13+00:00

[ Upstream commit 749439bfac6e1a2932c582e2699f91d329658196 ]

The logic in __ip6_append_data() assumes that the MTU is at least large
enough for the headers.  A device's MTU may be adjusted after being
added while sendmsg() is processing data, resulting in
__ip6_append_data() seeing any MTU.  For an mtu smaller than the size of
the fragmentation header, the math results in a negative 'maxfraglen',
which causes problems when refragmenting any previous skb in the
skb_write_queue, leaving it possibly malformed.

Instead sendmsg returns EINVAL when the mtu is calculated to be less
than IPV6_MIN_MTU.

Found by syzkaller:
kernel BUG at ./include/linux/skbuff.h:2064!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 14216 Comm: syz-executor5 Not tainted 4.13.0-rc4+ #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d0b68580 task.stack: ffff8801ac6b8000
RIP: 0010:__skb_pull include/linux/skbuff.h:2064 [inline]
RIP: 0010:__ip6_make_skb+0x18cf/0x1f70 net/ipv6/ip6_output.c:1617
RSP: 0018:ffff8801ac6bf570 EFLAGS: 00010216
RAX: 0000000000010000 RBX: 0000000000000028 RCX: ffffc90003cce000
RDX: 00000000000001b8 RSI: ffffffff839df06f RDI: ffff8801d9478ca0
RBP: ffff8801ac6bf780 R08: ffff8801cc3f1dbc R09: 0000000000000000
R10: ffff8801ac6bf7a0 R11: 43cb4b7b1948a9e7 R12: ffff8801cc3f1dc8
R13: ffff8801cc3f1d40 R14: 0000000000001036 R15: dffffc0000000000
FS:  00007f43d740c700(0000) GS:ffff8801dc100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7834984000 CR3: 00000001d79b9000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ip6_finish_skb include/net/ipv6.h:911 [inline]
 udp_v6_push_pending_frames+0x255/0x390 net/ipv6/udp.c:1093
 udpv6_sendmsg+0x280d/0x31a0 net/ipv6/udp.c:1363
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 SYSC_sendto+0x352/0x5a0 net/socket.c:1750
 SyS_sendto+0x40/0x50 net/socket.c:1718
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512e9
RSP: 002b:00007f43d740bc08 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000007180a8 RCX: 00000000004512e9
RDX: 000000000000002e RSI: 0000000020d08000 RDI: 0000000000000005
RBP: 0000000000000086 R08: 00000000209c1000 R09: 000000000000001c
R10: 0000000000040800 R11: 0000000000000216 R12: 00000000004b9c69
R13: 00000000ffffffff R14: 0000000000000005 R15: 00000000202c2000
Code: 9e 01 fe e9 c5 e8 ff ff e8 7f 9e 01 fe e9 4a ea ff ff 48 89 f7 e8 52 9e 01 fe e9 aa eb ff ff e8 a8 b6 cf fd 0f 0b e8 a1 b6 cf fd <0f> 0b 49 8d 45 78 4d 8d 45 7c 48 89 85 78 fe ff ff 49 8d 85 ba
RIP: __skb_pull include/linux/skbuff.h:2064 [inline] RSP: ffff8801ac6bf570
RIP: __ip6_make_skb+0x18cf/0x1f70 net/ipv6/ip6_output.c:1617 RSP: ffff8801ac6bf570

Reported-by: syzbot 
Signed-off-by: Mike Maloney 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL

2018-01-31T11:06:12+00:00

[ Upstream commit e9191ffb65d8e159680ce0ad2224e1acbde6985c ]

Commit 513674b5a2c9 ("net: reevalulate autoflowlabel setting after
sysctl setting") removed the initialisation of
ipv6_pinfo::autoflowlabel and added a second flag to indicate
whether this field or the net namespace default should be used.

The getsockopt() handling for this case was not updated, so it
currently returns 0 for all sockets for which IPV6_AUTOFLOWLABEL is
not explicitly enabled.  Fix it to return the effective value, whether
that has been set at the socket or net namespace level.

Fixes: 513674b5a2c9 ("net: reevalulate autoflowlabel setting after sysctl ...")
Signed-off-by: Ben Hutchings 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netfilter: fix IS_ERR_VALUE usage

2018-01-31T11:06:10+00:00

commit 92b4423e3a0bc5d43ecde4bcad871f8b5ba04efd upstream.

This is a forward-port of the original patch from Andrzej Hajda,
he said:

"IS_ERR_VALUE should be used only with unsigned long type.
Otherwise it can work incorrectly. To achieve this function
xt_percpu_counter_alloc is modified to return unsigned long,
and its result is assigned to temporary variable to perform
error checking, before assigning to .pcnt field.

The patch follows conclusion from discussion on LKML [1][2].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2120927
[2]: http://permalink.gmane.org/gmane.linux.kernel/2150581"

Original patch from Andrzej is here:

http://patchwork.ozlabs.org/patch/582970/

This patch has clashed with input validation fixes for x_tables.

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman 
Acked-by: Michal Kubecek

netfilter: use fwmark_reflect in nf_send_reset

2018-01-31T11:06:10+00:00

commit cc31d43b4154ad5a7d8aa5543255a93b7e89edc2 upstream.

Otherwise, RST packets generated by ipt_REJECT always have mark 0 when
the routing is checked later in the same code path.

Fixes: e110861f8609 ("net: add a sysctl to reflect the fwmark on replies")
Cc: Lorenzo Colitti 
Signed-off-by: Pau Espin Pedrol 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_dup_ipv6: set again FLOWI_FLAG_KNOWN_NH at flowi6_flags

2018-01-31T11:06:10+00:00

commit 83170f3beccccd7ceb4f9a0ac0c4dc736afde90c upstream.

With the commit 48e8aa6e3137 ("ipv6: Set FLOWI_FLAG_KNOWN_NH at
flowi6_flags") ip6_pol_route() callers were asked to to set the
FLOWI_FLAG_KNOWN_NH properly and xt_TEE was updated accordingly,
but with the later refactor in commit bbde9fc1824a ("netfilter:
factor out packet duplication for IPv4/IPv6") the flowi6_flags
update was lost.
This commit re-add it just before the routing decision.

Fixes: bbde9fc1824a ("netfilter: factor out packet duplication for IPv4/IPv6")
Signed-off-by: Paolo Abeni 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

netfilter: x_tables: speed up jump target validation

2018-01-31T11:06:10+00:00

commit f4dc77713f8016d2e8a3295e1c9c53a21f296def upstream.

The dummy ruleset I used to test the original validation change was broken,
most rules were unreachable and were not tested by mark_source_chains().

In some cases rulesets that used to load in a few seconds now require
several minutes.

sample ruleset that shows the behaviour:

echo "*filter"
for i in $(seq 0 100000);do
        printf ":chain_%06x - [0:0]\n" $i
done
for i in $(seq 0 100000);do
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
   printf -- "-A INPUT -j chain_%06x\n" $i
done
echo COMMIT

[ pipe result into iptables-restore ]

This ruleset will be about 74mbyte in size, with ~500k searches
though all 500k[1] rule entries. iptables-restore will take forever
(gave up after 10 minutes)

Instead of always searching the entire blob for a match, fill an
array with the start offsets of every single ipt_entry struct,
then do a binary search to check if the jump target is present or not.

After this change ruleset restore times get again close to what one
gets when reverting 36472341017529e (~3 seconds on my workstation).

[1] every user-defined rule gets an implicit RETURN, so we get
300k jumps + 100k userchains + 100k returns -> 500k rule entries

Fixes: 36472341017529e ("netfilter: x_tables: validate targets of jumps")
Reported-by: Jeff Wu 
Tested-by: Jeff Wu 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Michal Kubecek 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix possible mem leaks in ipv6_make_skb()

2018-01-17T08:35:30+00:00

[ Upstream commit 862c03ee1deb7e19e0f9931682e0294ecd1fcaf9 ]

ip6_setup_cork() might return an error, while memory allocations have
been done and must be rolled back.

Fixes: 6422398c2ab0 ("ipv6: introduce ipv6_make_skb")
Signed-off-by: Eric Dumazet 
Cc: Vlad Yasevich 
Reported-by: Mike Maloney 
Acked-by:  Mike Maloney 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip6_tunnel: disable dst caching if tunnel is dual-stack

2018-01-17T08:35:29+00:00

[ Upstream commit 23263ec86a5f44312d2899323872468752324107 ]

When an ip6_tunnel is in mode 'any', where the transport layer
protocol can be either 4 or 41, dst_cache must be disabled.

This is because xfrm policies might apply to only one of the two
protocols. Caching dst would cause xfrm policies for one protocol
incorrectly used for the other.

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

tcp md5sig: Use skb's saddr when replying to an incoming segment

2018-01-02T19:33:25+00:00

[ Upstream commit 30791ac41927ebd3e75486f9504b6d2280463bf0 ]

The MD5-key that belongs to a connection is identified by the peer's
IP-address. When we are in tcp_v4(6)_reqsk_send_ack(), we are replying
to an incoming segment from tcp_check_req() that failed the seq-number
checks.

Thus, to find the correct key, we need to use the skb's saddr and not
the daddr.

This bug seems to have been there since quite a while, but probably got
unnoticed because the consequences are not catastrophic. We will call
tcp_v4_reqsk_send_ack only to send a challenge-ACK back to the peer,
thus the connection doesn't really fail.

Fixes: 9501f9722922 ("tcp md5sig: Let the caller pass appropriate key for tcp_v{4,6}_do_calc_md5_hash().")
Signed-off-by: Christoph Paasch 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman