linux-stable.git/net/core, branch v5.3.11

bpf: lwtunnel: Fix reroute supplying invalid dst

2019-11-12T18:27:33+00:00

[ Upstream commit 9e8acd9c44a0dd52b2922eeb82398c04e356c058 ]

The dst in bpf_input() has lwtstate field set. As it is of the
LWTUNNEL_ENCAP_BPF type, lwtstate->data is struct bpf_lwt. When the bpf
program returns BPF_LWT_REROUTE, ip_route_input_noref is directly called on
this skb. This causes invalid memory access, as ip_route_input_slow calls
skb_tunnel_info(skb) that expects the dst->lwstate->data to be
struct ip_tunnel_info. This results to struct bpf_lwt being accessed as
struct ip_tunnel_info.

Drop the dst before calling the IP route input functions (both for IPv4 and
IPv6).

Reported by KASAN.

Fixes: 3bd0b15281af ("bpf: add handling of BPF_LWT_REROUTE to lwt_bpf.c")
Signed-off-by: Jiri Benc 
Signed-off-by: Alexei Starovoitov 
Acked-by: Peter Oskolkov 
Link: https://lore.kernel.org/bpf/111664d58fe4e9dd9c8014bb3d0b2dab93086a9e.1570609794.git.jbenc@redhat.com
Signed-off-by: Sasha Levin

net/tls: fix sk_msg trim on fallback to copy mode

2019-11-12T18:26:39+00:00

[ Upstream commit 683916f6a84023407761d843048f1aea486b2612 ]

sk_msg_trim() tries to only update curr pointer if it falls into
the trimmed region. The logic, however, does not take into the
account pointer wrapping that sk_msg_iter_var_prev() does nor
(as John points out) the fact that msg->sg is a ring buffer.

This means that when the message was trimmed completely, the new
curr pointer would have the value of MAX_MSG_FRAGS - 1, which is
neither smaller than any other value, nor would it actually be
correct.

Special case the trimming to 0 length a little bit and rework
the comparison between curr and end to take into account wrapping.

This bug caused the TLS code to not copy all of the message, if
zero copy filled in fewer sg entries than memcopy would need.

Big thanks to Alexander Potapenko for the non-KMSAN reproducer.

v2:
 - take into account that msg->sg is a ring buffer (John).

Link: https://lore.kernel.org/netdev/20191030160542.30295-1-jakub.kicinski@netronome.com/ (v1)

Fixes: d829e9c4112b ("tls: convert to generic sk_msg interface")
Reported-by: syzbot+f8495bff23a879a6d0bd@syzkaller.appspotmail.com
Reported-by: syzbot+6f50c99e8f6194bf363f@syzkaller.appspotmail.com
Co-developed-by: John Fastabend 
Signed-off-by: Jakub Kicinski 
Signed-off-by: John Fastabend 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net/flow_dissector: switch to siphash

2019-11-10T10:34:55+00:00

commit 55667441c84fa5e0911a0aac44fb059c15ba6da2 upstream.

UDP IPv6 packets auto flowlabels are using a 32bit secret
(static u32 hashrnd in net/core/flow_dissector.c) and
apply jhash() over fields known by the receivers.

Attackers can easily infer the 32bit secret and use this information
to identify a device and/or user, since this 32bit secret is only
set at boot time.

Really, using jhash() to generate cookies sent on the wire
is a serious security concern.

Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be
a dead end. Trying to periodically change the secret (like in sch_sfq.c)
could change paths taken in the network for long lived flows.

Let's switch to siphash, as we did in commit df453700e8d8
("inet: switch IP ID generator to siphash")

Using a cryptographically strong pseudo random function will solve this
privacy issue and more generally remove other weak points in the stack.

Packet schedulers using skb_get_hash_perturb() benefit from this change.

Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default")
Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels")
Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit")
Signed-off-by: Eric Dumazet 
Reported-by: Jonathan Berger 
Reported-by: Amit Klein 
Reported-by: Benny Pinkas 
Cc: Tom Herbert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

keys: Fix memory leak in copy_net_ns

2019-11-10T10:34:47+00:00

[ Upstream commit 82ecff655e7968151b0047f1b5de03b249e5c1c4 ]

If copy_net_ns() failed after net_alloc(), net->key_domain is leaked.
Fix this, by freeing key_domain in error path.

syzbot report:
BUG: memory leak
unreferenced object 0xffff8881175007e0 (size 32):
  comm "syz-executor902", pid 7069, jiffies 4294944350 (age 28.400s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000a83ed741>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<00000000a83ed741>] slab_post_alloc_hook mm/slab.h:439 [inline]
    [<00000000a83ed741>] slab_alloc mm/slab.c:3326 [inline]
    [<00000000a83ed741>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
    [<0000000059fc92b9>] kmalloc include/linux/slab.h:547 [inline]
    [<0000000059fc92b9>] kzalloc include/linux/slab.h:742 [inline]
    [<0000000059fc92b9>] net_alloc net/core/net_namespace.c:398 [inline]
    [<0000000059fc92b9>] copy_net_ns+0xb2/0x220 net/core/net_namespace.c:445
    [<00000000a9d74bbc>] create_new_namespaces+0x141/0x2a0 kernel/nsproxy.c:103
    [<000000008047d645>] unshare_nsproxy_namespaces+0x7f/0x100 kernel/nsproxy.c:202
    [<000000005993ea6e>] ksys_unshare+0x236/0x490 kernel/fork.c:2674
    [<0000000019417e75>] __do_sys_unshare kernel/fork.c:2742 [inline]
    [<0000000019417e75>] __se_sys_unshare kernel/fork.c:2740 [inline]
    [<0000000019417e75>] __x64_sys_unshare+0x16/0x20 kernel/fork.c:2740
    [<00000000f4c5f2c8>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296
    [<0000000038550184>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

syzbot also reported other leak in copy_net_ns -> setup_net.
This problem is already fixed by cf47a0b882a4e5f6b34c7949d7b293e9287f1972.

Fixes: 9b242610514f ("keys: Network namespace domain tag")
Reported-and-tested-by: syzbot+3b3296d032353c33184b@syzkaller.appspotmail.com
Signed-off-by: Takeshi Misawa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: add READ_ONCE() annotation in __skb_wait_for_more_packets()

2019-11-10T10:34:45+00:00

[ Upstream commit 7c422d0ce97552dde4a97e6290de70ec6efb0fc6 ]

__skb_wait_for_more_packets() can be called while other cpus
can feed packets to the socket receive queue.

KCSAN reported :

BUG: KCSAN: data-race in __skb_wait_for_more_packets / __udp_enqueue_schedule_skb

write to 0xffff888102e40b58 of 8 bytes by interrupt on cpu 0:
 __skb_insert include/linux/skbuff.h:1852 [inline]
 __skb_queue_before include/linux/skbuff.h:1958 [inline]
 __skb_queue_tail include/linux/skbuff.h:1991 [inline]
 __udp_enqueue_schedule_skb+0x2d7/0x410 net/ipv4/udp.c:1470
 __udp_queue_rcv_skb net/ipv4/udp.c:1940 [inline]
 udp_queue_rcv_one_skb+0x7bd/0xc70 net/ipv4/udp.c:2057
 udp_queue_rcv_skb+0xb5/0x400 net/ipv4/udp.c:2074
 udp_unicast_rcv_skb.isra.0+0x7e/0x1c0 net/ipv4/udp.c:2233
 __udp4_lib_rcv+0xa44/0x17c0 net/ipv4/udp.c:2300
 udp_rcv+0x2b/0x40 net/ipv4/udp.c:2470
 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
 process_backlog+0x1d3/0x420 net/core/dev.c:5955

read to 0xffff888102e40b58 of 8 bytes by task 13035 on cpu 1:
 __skb_wait_for_more_packets+0xfa/0x320 net/core/datagram.c:100
 __skb_recv_udp+0x374/0x500 net/ipv4/udp.c:1683
 udp_recvmsg+0xe1/0xb10 net/ipv4/udp.c:1712
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec+0x5c/0x70 net/socket.c:871
 ___sys_recvmsg+0x1a0/0x3e0 net/socket.c:2480
 do_recvmmsg+0x19a/0x5c0 net/socket.c:2601
 __sys_recvmmsg+0x1ef/0x200 net/socket.c:2680
 __do_sys_recvmmsg net/socket.c:2703 [inline]
 __se_sys_recvmmsg net/socket.c:2696 [inline]
 __x64_sys_recvmmsg+0x89/0xb0 net/socket.c:2696
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 13035 Comm: syz-executor.3 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

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

net: use skb_queue_empty_lockless() in busy poll contexts

2019-11-10T10:34:45+00:00

[ Upstream commit 3f926af3f4d688e2e11e7f8ed04e277a14d4d4a4 ]

Busy polling usually runs without locks.
Let's use skb_queue_empty_lockless() instead of skb_queue_empty()

Also uses READ_ONCE() in __skb_try_recv_datagram() to address
a similar potential problem.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: use skb_queue_empty_lockless() in poll() handlers

2019-11-10T10:34:44+00:00

[ Upstream commit 3ef7cf57c72f32f61e97f8fa401bc39ea1f1a5d4 ]

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Zeroing the structure ethtool_wolinfo in ethtool_get_wol()

2019-11-10T10:34:40+00:00

[ Upstream commit 5ff223e86f5addbfae26419cbb5d61d98f6fbf7d ]

memset() the structure ethtool_wolinfo that has padded bytes
but the padded bytes have not been zeroed out.

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

net: rtnetlink: fix a typo fbd -> fdb

2019-11-10T10:34:39+00:00

[ Upstream commit 8b73018fe44521c1cf59d7bac53624c87d3f10e2 ]

A simple typo fix in the nl error message (fbd -> fdb).

CC: David Ahern 
Fixes: 8c6e137fbc7f ("rtnetlink: Update rtnl_fdb_dump for strict data checking")
Signed-off-by: Nikolay Aleksandrov 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netns: fix GFP flags in rtnl_net_notifyid()

2019-11-10T10:34:38+00:00

[ Upstream commit d4e4fdf9e4a27c87edb79b1478955075be141f67 ]

In rtnl_net_notifyid(), we certainly can't pass a null GFP flag to
rtnl_notify(). A GFP_KERNEL flag would be fine in most circumstances,
but there are a few paths calling rtnl_net_notifyid() from atomic
context or from RCU critical sections. The later also precludes the use
of gfp_any() as it wouldn't detect the RCU case. Also, the nlmsg_new()
call is wrong too, as it uses GFP_KERNEL unconditionally.

Therefore, we need to pass the GFP flags as parameter and propagate it
through function calls until the proper flags can be determined.

In most cases, GFP_KERNEL is fine. The exceptions are:
  * openvswitch: ovs_vport_cmd_get() and ovs_vport_cmd_dump()
    indirectly call rtnl_net_notifyid() from RCU critical section,

  * rtnetlink: rtmsg_ifinfo_build_skb() already receives GFP flags as
    parameter.

Also, in ovs_vport_cmd_build_info(), let's change the GFP flags used
by nlmsg_new(). The function is allowed to sleep, so better make the
flags consistent with the ones used in the following
ovs_vport_cmd_fill_info() call.

Found by code inspection.

Fixes: 9a9634545c70 ("netns: notify netns id events")
Signed-off-by: Guillaume Nault 
Acked-by: Nicolas Dichtel 
Acked-by: Pravin B Shelar 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman