linux-stable.git/net/ipv4, branch v4.4.142

netfilter: x_tables: initialise match/target check parameter struct

2018-07-17T09:31:46+00:00

commit c568503ef02030f169c9e19204def610a3510918 upstream.

syzbot reports following splat:

BUG: KMSAN: uninit-value in ebt_stp_mt_check+0x24b/0x450
 net/bridge/netfilter/ebt_stp.c:162
 ebt_stp_mt_check+0x24b/0x450 net/bridge/netfilter/ebt_stp.c:162
 xt_check_match+0x1438/0x1650 net/netfilter/x_tables.c:506
 ebt_check_match net/bridge/netfilter/ebtables.c:372 [inline]
 ebt_check_entry net/bridge/netfilter/ebtables.c:702 [inline]

The uninitialised access is
   xt_mtchk_param->nft_compat

... which should be set to 0.
Fix it by zeroing the struct beforehand, same for tgchk.

ip(6)tables targetinfo uses c99-style initialiser, so no change
needed there.

Reported-by: syzbot+da4494182233c23a5fcf@syzkaller.appspotmail.com
Fixes: 55917a21d0cc0 ("netfilter: x_tables: add context to know if extension runs from nft_compat")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

ipv4: Fix error return value in fib_convert_metrics()

2018-07-11T14:03:47+00:00

The validation code modified by commit 5b5e7a0de2bb ("net: metrics:
add proper netlink validation") is organised differently in older
kernel versions.  The fib_convert_metrics() function that is modified
in the backports to 4.4 and 4.9 needs to returns an error code, not a
success flag.

Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

tcp: verify the checksum of the first data segment in a new connection

2018-07-03T09:21:25+00:00

[ Upstream commit 4fd44a98ffe0d048246efef67ed640fdf2098a62 ]

commit 079096f103fa ("tcp/dccp: install syn_recv requests into ehash
table") introduced an optimization for the handling of child sockets
created for a new TCP connection.

But this optimization passes any data associated with the last ACK of the
connection handshake up the stack without verifying its checksum, because it
calls tcp_child_process(), which in turn calls tcp_rcv_state_process()
directly.  These lower-level processing functions do not do any checksum
verification.

Insert a tcp_checksum_complete call in the TCP_NEW_SYN_RECEIVE path to
fix this.

Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Frank van der Linden 
Signed-off-by: Eric Dumazet 
Tested-by: Balbir Singh 
Reviewed-by: Balbir Singh 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: do not overshoot window_clamp in tcp_rcv_space_adjust()

2018-07-03T09:21:24+00:00

commit 02db55718d53f9d426cee504c27fb768e9ed4ffe upstream.

While rcvbuf is properly clamped by tcp_rmem[2], rcvwin
is left to a potentially too big value.

It has no serious effect, since :
1) tcp_grow_window() has very strict checks.
2) window_clamp can be mangled by user space to any value anyway.

tcp_init_buffer_space() and companions use tcp_full_space(),
we use tcp_win_from_space() to avoid reloading sk->sk_rcvbuf

Signed-off-by: Eric Dumazet 
Acked-by: Soheil Hassas Yeganeh 
Acked-by: Wei Wang 
Acked-by: Neal Cardwell 
Signed-off-by: David S. Miller 
Cc: Benjamin Gilbert 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

net: metrics: add proper netlink validation

2018-06-13T14:15:29+00:00

[ Upstream commit 5b5e7a0de2bbf2a1afcd9f49e940010e9fb80d53 ]

Before using nla_get_u32(), better make sure the attribute
is of the proper size.

Code recently was changed, but bug has been there from beginning
of git.

BUG: KMSAN: uninit-value in rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746
CPU: 1 PID: 14139 Comm: syz-executor6 Not tainted 4.17.0-rc5+ #103
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
 __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:686
 rtnetlink_put_metrics+0x553/0x960 net/core/rtnetlink.c:746
 fib_dump_info+0xc42/0x2190 net/ipv4/fib_semantics.c:1361
 rtmsg_fib+0x65f/0x8c0 net/ipv4/fib_semantics.c:419
 fib_table_insert+0x2314/0x2b50 net/ipv4/fib_trie.c:1287
 inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779
 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x455a09
RSP: 002b:00007faae5fd8c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007faae5fd96d4 RCX: 0000000000455a09
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000005d0 R14: 00000000006fdc20 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:294 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:685
 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:529
 fib_convert_metrics net/ipv4/fib_semantics.c:1056 [inline]
 fib_create_info+0x2d46/0x9dc0 net/ipv4/fib_semantics.c:1150
 fib_table_insert+0x3e4/0x2b50 net/ipv4/fib_trie.c:1146
 inet_rtm_newroute+0x210/0x340 net/ipv4/fib_frontend.c:779
 rtnetlink_rcv_msg+0xa32/0x1560 net/core/rtnetlink.c:4646
 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2448
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:4664
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x1678/0x1750 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x104f/0x1350 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan.c:322
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2753 [inline]
 __kmalloc_node_track_caller+0xb32/0x11b0 mm/slub.c:4395
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
 netlink_sendmsg+0x76e/0x1350 net/netlink/af_netlink.c:1876
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg net/socket.c:639 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2117
 __sys_sendmsg net/socket.c:2155 [inline]
 __do_sys_sendmsg net/socket.c:2164 [inline]
 __se_sys_sendmsg net/socket.c:2162 [inline]
 __x64_sys_sendmsg+0x331/0x460 net/socket.c:2162
 do_syscall_64+0x152/0x230 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: a919525ad832 ("net: Move fib_convert_metrics to metrics file")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: remove warning in ip_recv_error

2018-06-13T14:15:28+00:00

[ Upstream commit 730c54d59403658a62af6517338fa8d4922c1b28 ]

A precondition check in ip_recv_error triggered on an otherwise benign
race. Remove the warning.

The warning triggers when passing an ipv6 socket to this ipv4 error
handling function. RaceFuzzer was able to trigger it due to a race
in setsockopt IPV6_ADDRFORM.

  ---
  CPU0
    do_ipv6_setsockopt
      sk->sk_socket->ops = &inet_dgram_ops;

  ---
  CPU1
    sk->sk_prot->recvmsg
      udp_recvmsg
        ip_recv_error
          WARN_ON_ONCE(sk->sk_family == AF_INET6);

  ---
  CPU0
    do_ipv6_setsockopt
      sk->sk_family = PF_INET;

This socket option converts a v6 socket that is connected to a v4 peer
to an v4 socket. It updates the socket on the fly, changing fields in
sk as well as other structs. This is inherently non-atomic. It races
with the lockless udp_recvmsg path.

No other code makes an assumption that these fields are updated
atomically. It is benign here, too, as ip_recv_error cares only about
the protocol of the skbs enqueued on the error queue, for which
sk_family is not a precise predictor (thanks to another isue with
IPV6_ADDRFORM).

Link: http://lkml.kernel.org/r/20180518120826.GA19515@dragonet.kaist.ac.kr
Fixes: 7ce875e5ecb8 ("ipv4: warn once on passing AF_INET6 socket to ip_recv_error")
Reported-by: DaeRyong Jeong 
Suggested-by: Eric Dumazet 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: avoid integer overflows in tcp_rcv_space_adjust()

2018-06-06T14:46:21+00:00

commit 607065bad9931e72207b0cac365d7d4abc06bd99 upstream.

When using large tcp_rmem[2] values (I did tests with 500 MB),
I noticed overflows while computing rcvwin.

Lets fix this before the following patch.

Signed-off-by: Eric Dumazet 
Acked-by: Soheil Hassas Yeganeh 
Acked-by: Wei Wang 
Acked-by: Neal Cardwell 
Signed-off-by: David S. Miller 
[Backport: sysctl_tcp_rmem is not Namespace-ify'd in older kernels]
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

Revert "vti4: Don't override MTU passed on link creation via IFLA_MTU"

2018-05-30T20:11:35+00:00

This reverts commit 33cebc976c3b77bdf8f3fb4478cf776131ebfe4f which is
03080e5ec727 ("vti4: Don't override MTU passed on link creation via
IFLA_MTU") upstream as it causes test failures.

This commit should not have been backported to anything older than 4.16,
despite what the changelog said as the mtu must be set in older kernels,
unlike is needed in 4.16 and newer.

Thanks to Alistair Strachan for the debugging help figuring this out,
and for 'git bisect' for making my life a whole lot easier.

Cc: Alistair Strachan 
Cc: Stefano Brivio 
Cc: Sabrina Dubroca 
Cc: Steffen Klassert 
Cc: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

vti4: Don't override MTU passed on link creation via IFLA_MTU

2018-05-30T05:49:05+00:00

[ Upstream commit 03080e5ec72740c1a62e6730f2a5f3f114f11b19 ]

Don't hardcode a MTU value on vti tunnel initialization,
ip_tunnel_newlink() is able to deal with this already. See also
commit ffc2b6ee4174 ("ip_gre: fix IFLA_MTU ignored on NEWLINK").

Fixes: 1181412c1a67 ("net/ipv4: VTI support new module for ip_vti.")
Signed-off-by: Stefano Brivio 
Acked-by: Sabrina Dubroca 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

vti4: Don't count header length twice on tunnel setup

2018-05-30T05:49:05+00:00

[ Upstream commit dd1df24737727e119c263acf1be2a92763938297 ]

This re-introduces the effect of commit a32452366b72 ("vti4:
Don't count header length twice.") which was accidentally
reverted by merge commit f895f0cfbb77 ("Merge branch 'master' of
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec").

The commit message from Steffen Klassert said:

    We currently count the size of LL_MAX_HEADER and struct iphdr
    twice for vti4 devices, this leads to a wrong device mtu.
    The size of LL_MAX_HEADER and struct iphdr is already counted in
    ip_tunnel_bind_dev(), so don't do it again in vti_tunnel_init().

And this is still the case now: ip_tunnel_bind_dev() already
accounts for the header length of the link layer (not
necessarily LL_MAX_HEADER, if the output device is found), plus
one IP header.

For example, with a vti device on top of veth, with MTU of 1500,
the existing implementation would set the initial vti MTU to
1332, accounting once for LL_MAX_HEADER (128, included in
hard_header_len by vti) and twice for the same IP header (once
from hard_header_len, once from ip_tunnel_bind_dev()).

It should instead be 1480, because ip_tunnel_bind_dev() is able
to figure out that the output device is veth, so no additional
link layer header is attached, and will properly count one
single IP header.

The existing issue had the side effect of avoiding PMTUD for
most xfrm policies, by arbitrarily lowering the initial MTU.
However, the only way to get a consistent PMTU value is to let
the xfrm PMTU discovery do its course, and commit d6af1a31cc72
("vti: Add pmtu handling to vti_xmit.") now takes care of local
delivery cases where the application ignores local socket
notifications.

Fixes: b9959fd3b0fa ("vti: switch to new ip tunnel code")
Fixes: f895f0cfbb77 ("Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec")
Signed-off-by: Stefano Brivio 
Acked-by: Sabrina Dubroca 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman