linux-stable.git/net/decnet, branch v4.1.45

decnet: always not take dst->__refcnt when inserting dst into hash table

2017-07-31T17:37:48+00:00

[ Upstream commit 76371d2e3ad1f84426a30ebcd8c3b9b98f4c724f ]

In the existing dn_route.c code, dn_route_output_slow() takes
dst->__refcnt before calling dn_insert_route() while dn_route_input_slow()
does not take dst->__refcnt before calling dn_insert_route().
This makes the whole routing code very buggy.
In dn_dst_check_expire(), dnrt_free() is called when rt expires. This
makes the routes inserted by dn_route_output_slow() not able to be
freed as the refcnt is not released.
In dn_dst_gc(), dnrt_drop() is called to release rt which could
potentially cause the dst->__refcnt to be dropped to -1.
In dn_run_flush(), dst_free() is called to release all the dst. Again,
it makes the dst inserted by dn_route_output_slow() not able to be
released and also, it does not wait on the rcu and could potentially
cause crash in the path where other users still refer to this dst.

This patch makes sure both input and output path do not take
dst->__refcnt before calling dn_insert_route() and also makes sure
dnrt_free()/dst_free() is called when removing dst from the hash table.
The only difference between those 2 calls is that dnrt_free() waits on
the rcu while dst_free() does not.

Signed-off-by: Wei Wang 
Acked-by: Martin KaFai Lau 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

decnet: dn_rtmsg: Improve input length sanitization in dnrmg_receive_user_skb

2017-07-31T17:37:48+00:00

[ Upstream commit 85eac2ba35a2dbfbdd5767c7447a4af07444a5b4 ]

Verify that the length of the socket buffer is sufficient to cover the
entire nlh->nlmsg_len field before accessing that field for further
input sanitization. If the client only supplies 1-3 bytes of data in
sk_buff, then nlh->nlmsg_len remains partially uninitialized and
contains leftover memory from the corresponding kernel allocation.
Operating on such data may result in indeterminate evaluation of the
nlmsg_len < sizeof(*nlh) expression.

The bug was discovered by a runtime instrumentation designed to detect
use of uninitialized memory in the kernel. The patch prevents this and
other similar tools (e.g. KMSAN) from flagging this behavior in the future.

Signed-off-by: Mateusz Jurczyk 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

decnet: Do not build routes to devices without decnet private data.

2016-07-11T03:07:20+00:00

[ Upstream commit a36a0d4008488fa545c74445d69eaf56377d5d4e ]

In particular, make sure we check for decnet private presence
for loopback devices.

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

net: add validation for the socket syscall protocol argument

2016-01-23T04:54:13+00:00

[ Upstream commit 79462ad02e861803b3840cc782248c7359451cd9 ]

郭永刚 reported that one could simply crash the kernel as root by
using a simple program:

	int socket_fd;
	struct sockaddr_in addr;
	addr.sin_port = 0;
	addr.sin_addr.s_addr = INADDR_ANY;
	addr.sin_family = 10;

	socket_fd = socket(10,3,0x40000000);
	connect(socket_fd , &addr,16);

AF_INET, AF_INET6 sockets actually only support 8-bit protocol
identifiers. inet_sock's skc_protocol field thus is sized accordingly,
thus larger protocol identifiers simply cut off the higher bits and
store a zero in the protocol fields.

This could lead to e.g. NULL function pointer because as a result of
the cut off inet_num is zero and we call down to inet_autobind, which
is NULL for raw sockets.

kernel: Call Trace:
kernel:  [] ? inet_autobind+0x2e/0x70
kernel:  [] inet_dgram_connect+0x54/0x80
kernel:  [] SYSC_connect+0xd9/0x110
kernel:  [] ? ptrace_notify+0x5b/0x80
kernel:  [] ? syscall_trace_enter_phase2+0x108/0x200
kernel:  [] SyS_connect+0xe/0x10
kernel:  [] tracesys_phase2+0x84/0x89

I found no particular commit which introduced this problem.

CVE: CVE-2015-8543
Cc: Cong Wang 
Reported-by: 郭永刚 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netfilter: Pass socket pointer down through okfn().

2015-04-07T19:25:55+00:00

On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.

Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-04-07T02:34:15+00:00

Conflicts:
	drivers/net/ethernet/mellanox/mlx4/cmd.c
	net/core/fib_rules.c
	net/ipv4/fib_frontend.c

The fib_rules.c and fib_frontend.c conflicts were locking adjustments
in 'net' overlapping addition and removal of code in 'net-next'.

The mlx4 conflict was a bug fix in 'net' happening in the same
place a constant was being replaced with a more suitable macro.

Signed-off-by: David S. Miller

netfilter: Make nf_hookfn use nf_hook_state.

2015-04-04T16:31:38+00:00

Pass the nf_hook_state all the way down into the hook
functions themselves.

Signed-off-by: David S. Miller

net: move fib_rules_unregister() under rtnl lock

2015-04-03T00:52:34+00:00

We have to hold rtnl lock for fib_rules_unregister()
otherwise the following race could happen:

fib_rules_unregister():	fib_nl_delrule():
...				...
...				ops = lookup_rules_ops();
list_del_rcu(&ops->list);
				list_for_each_entry(ops->rules) {
fib_rules_cleanup_ops(ops);	  ...
  list_del_rcu();		  list_del_rcu();
				}

Note, net->rules_mod_lock is actually not needed at all,
either upper layer netns code or rtnl lock guarantees
we are safe.

Cc: Alexander Duyck 
Cc: Thomas Graf 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller

net: Remove protocol from struct dst_ops

2015-03-09T20:06:10+00:00

After my change to neigh_hh_init to obtain the protocol from the
neigh_table there are no more users of protocol in struct dst_ops.
Remove the protocol field from dst_ops and all of it's initializers.

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller

DECnet: Only use neigh_ops for adding the link layer header

2015-03-06T19:54:22+00:00

Other users users of the neighbour table use neigh->output as the method
to decided when and which link-layer header to place on a packet.
DECnet has been using neigh->output to decide which DECnet headers to
place on a packet depending which neighbour the packet is destined for.

The DECnet usage isn't totally wrong but it can run into problems if the
neighbour output function is run for a second time as the teql driver
and the bridge netfilter code can do.

Therefore to avoid pathologic problems later down the line and make the
neighbour code easier to understand by refactoring the decnet output
code to only use a neighbour method to add a link layer header to a
packet.

This is done by moving the neigbhour operations lookup from
dn_to_neigh_output to dn_neigh_output_packet.

Signed-off-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller