linux-stable.git/net/core, branch v3.18.48

net:Add sysctl_max_skb_frags

2017-02-08T08:43:05+00:00

commit 5f74f82ea34c0da80ea0b49192bb5ea06e063593 upstream.

Devices may have limits on the number of fragments in an skb they support.
Current codebase uses a constant as maximum for number of fragments one
skb can hold and use.
When enabling scatter/gather and running traffic with many small messages
the codebase uses the maximum number of fragments and may thereby violate
the max for certain devices.
The patch introduces a global variable as max number of fragments.

Signed-off-by: Hans Westgaard Ry 
Reviewed-by: Håkon Bugge 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tunnels: Don't apply GRO to multiple layers of encapsulation.

2017-01-15T14:49:53+00:00

[ Upstream commit fac8e0f579695a3ecbc4d3cac369139d7f819971 ]

When drivers express support for TSO of encapsulated packets, they
only mean that they can do it for one layer of encapsulation.
Supporting additional levels would mean updating, at a minimum,
more IP length fields and they are unaware of this.

No encapsulation device expresses support for handling offloaded
encapsulated packets, so we won't generate these types of frames
in the transmit path. However, GRO doesn't have a check for
multiple levels of encapsulation and will attempt to build them.

UDP tunnel GRO actually does prevent this situation but it only
handles multiple UDP tunnels stacked on top of each other. This
generalizes that solution to prevent any kind of tunnel stacking
that would cause problems.

Fixes: bf5a755f ("net-gre-gro: Add GRE support to the GRO stack")
Signed-off-by: Jesse Gross 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: fix infoleak in rtnetlink

2016-07-12T12:48:14+00:00

[ Upstream commit 5f8e44741f9f216e33736ea4ec65ca9ac03036e6 ]

The stack object “map” has a total size of 32 bytes. Its last 4
bytes are padding generated by compiler. These padding bytes are
not initialized and sent out via “nla_put”.

Signed-off-by: Kangjie Lu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: Fix skb_set_peeked use-after-free bug

2016-04-12T12:47:23+00:00

[ Upstream commit a0a2a6602496a45ae838a96db8b8173794b5d398 ]

The commit 738ac1ebb96d02e0d23bc320302a6ea94c612dec ("net: Clone
skb before setting peeked flag") introduced a use-after-free bug
in skb_recv_datagram.  This is because skb_set_peeked may create
a new skb and free the existing one.  As it stands the caller will
continue to use the old freed skb.

This patch fixes it by making skb_set_peeked return the new skb
(or the old one if unchanged).

Fixes: 738ac1ebb96d ("net: Clone skb before setting peeked flag")
Reported-by: Brenden Blanco 
Signed-off-by: Herbert Xu 
Tested-by: Brenden Blanco 
Reviewed-by: Konstantin Khlebnikov 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: Clone skb before setting peeked flag

2016-04-12T12:47:15+00:00

[ Upstream commit 738ac1ebb96d02e0d23bc320302a6ea94c612dec ]

Shared skbs must not be modified and this is crucial for broadcast
and/or multicast paths where we use it as an optimisation to avoid
unnecessary cloning.

The function skb_recv_datagram breaks this rule by setting peeked
without cloning the skb first.  This causes funky races which leads
to double-free.

This patch fixes this by cloning the skb and replacing the skb
in the list when setting skb->peeked.

Fixes: a59322be07c9 ("[UDP]: Only increment counter on first peek/recv")
Reported-by: Konstantin Khlebnikov 
Signed-off-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: bpf: reject invalid shifts

2016-02-15T20:42:44+00:00

[ Upstream commit 229394e8e62a4191d592842cf67e80c62a492937 ]

On ARM64, a BUG() is triggered in the eBPF JIT if a filter with a
constant shift that can't be encoded in the immediate field of the
UBFM/SBFM instructions is passed to the JIT.  Since these shifts
amounts, which are negative or >= regsize, are invalid, reject them in
the eBPF verifier and the classic BPF filter checker, for all
architectures.

Signed-off-by: Rabin Vincent 
Acked-by: Alexei Starovoitov 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: possible use after free in dst_release

2016-02-15T20:42:43+00:00

[ Upstream commit 07a5d38453599052aff0877b16bb9c1585f08609 ]

dst_release should not access dst->flags after decrementing
__refcnt to 0. The dst_entry may be in dst_busy_list and
dst_gc_task may dst_destroy it before dst_release gets a chance
to access dst->flags.

Fixes: d69bbf88c8d0 ("net: fix a race in dst_release()")
Fixes: 27b75c95f10d ("net: avoid RCU for NOCACHE dst")
Signed-off-by: Francesco Ruggeri 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: check both type and procotol for tcp sockets

2016-01-22T17:24:47+00:00

[ Upstream commit ac5cc977991d2dce85fc734a6c71ddb33f6fe3c1 ]

Dmitry reported the following out-of-bound access:

Call Trace:
 [] __asan_report_load4_noabort+0x3e/0x40
mm/kasan/report.c:294
 [] sock_setsockopt+0x1284/0x13d0 net/core/sock.c:880
 [<     inline     >] SYSC_setsockopt net/socket.c:1746
 [] SyS_setsockopt+0x1fe/0x240 net/socket.c:1729
 [] entry_SYSCALL_64_fastpath+0x16/0x7a
arch/x86/entry/entry_64.S:185

This is because we mistake a raw socket as a tcp socket.
We should check both sk->sk_type and sk->sk_protocol to ensure
it is a tcp socket.

Willem points out __skb_complete_tx_timestamp() needs to fix as well.

Reported-by: Dmitry Vyukov 
Cc: Willem de Bruijn 
Cc: Eric Dumazet 
Signed-off-by: Cong Wang 
Acked-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

skbuff: Fix offset error in skb_reorder_vlan_header

2016-01-15T23:41:51+00:00

[ Upstream commit f654861569872d10dcb79d9d7ca219b316f94ff0 ]

skb_reorder_vlan_header is called after the vlan header has
been pulled.  As a result the offset of the begining of
the mac header has been incrased by 4 bytes (VLAN_HLEN).
When moving the mac addresses, include this incrase in
the offset calcualation so that the mac addresses are
copied correctly.

Fixes: a6e18ff1117 (vlan: Fix untag operations of stacked vlans with REORDER_HEADER off)
CC: Nicolas Dichtel 
CC: Patrick McHardy 
Signed-off-by: Vladislav Yasevich 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

vlan: Fix untag operations of stacked vlans with REORDER_HEADER off

2016-01-15T23:41:51+00:00

[ Upstream commit a6e18ff111701b4ff6947605bfbe9594ec42a6e8 ]

When we have multiple stacked vlan devices all of which have
turned off REORDER_HEADER flag, the untag operation does not
locate the ethernet addresses correctly for nested vlans.
The reason is that in case of REORDER_HEADER flag being off,
the outer vlan headers are put back and the mac_len is adjusted
to account for the presense of the header.  Then, the subsequent
untag operation, for the next level vlan, always use VLAN_ETH_HLEN
to locate the begining of the ethernet header and that ends up
being a multiple of 4 bytes short of the actuall beginning
of the mac header (the multiple depending on the how many vlan
encapsulations ethere are).

As a reslult, if there are multiple levles of vlan devices
with REODER_HEADER being off, the recevied packets end up
being dropped.

To solve this, we use skb->mac_len as the offset.  The value
is always set on receive path and starts out as a ETH_HLEN.
The value is also updated when the vlan header manupations occur
so we know it will be correct.

Signed-off-by: Vladislav Yasevich 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin