linux-stable.git/net/core, branch v3.10.78

net: sysctl_net_core: check SNDBUF and RCVBUF for min length

2015-03-26T14:00:55+00:00

[ Upstream commit b1cb59cf2efe7971d3d72a7b963d09a512d994c9 ]

sysctl has sysctl.net.core.rmem_*/wmem_* parameters which can be
set to incorrect values. Given that 'struct sk_buff' allocates from
rcvbuf, incorrectly set buffer length could result to memory
allocation failures. For example, set them as follows:

    # sysctl net.core.rmem_default=64
      net.core.wmem_default = 64
    # sysctl net.core.wmem_default=64
      net.core.wmem_default = 64
    # ping localhost -s 1024 -i 0 > /dev/null

This could result to the following failure:

skbuff: skb_over_panic: text:ffffffff81628db4 len:-32 put:-32
head:ffff88003a1cc200 data:ffff88003a1cc200 tail:0xffffffe0 end:0xc0 dev:
kernel BUG at net/core/skbuff.c:102!
invalid opcode: 0000 [#1] SMP
...
task: ffff88003b7f5550 ti: ffff88003ae88000 task.ti: ffff88003ae88000
RIP: 0010:[]  [] skb_put+0xa1/0xb0
RSP: 0018:ffff88003ae8bc68  EFLAGS: 00010296
RAX: 000000000000008d RBX: 00000000ffffffe0 RCX: 0000000000000000
RDX: ffff88003fdcf598 RSI: ffff88003fdcd9c8 RDI: ffff88003fdcd9c8
RBP: ffff88003ae8bc88 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 00000000000002b2 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88003d3f7300 R15: ffff88000012a900
FS:  00007fa0e2b4a840(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000d0f7e0 CR3: 000000003b8fb000 CR4: 00000000000006f0
Stack:
 ffff88003a1cc200 00000000ffffffe0 00000000000000c0 ffffffff818cab1d
 ffff88003ae8bd68 ffffffff81628db4 ffff88003ae8bd48 ffff88003b7f5550
 ffff880031a09408 ffff88003b7f5550 ffff88000012aa48 ffff88000012ab00
Call Trace:
 [] unix_stream_sendmsg+0x2c4/0x470
 [] sock_write_iter+0x146/0x160
 [] new_sync_write+0x92/0xd0
 [] vfs_write+0xd6/0x180
 [] SyS_write+0x59/0xd0
 [] system_call_fastpath+0x12/0x17
Code: 00 00 48 89 44 24 10 8b 87 c8 00 00 00 48 89 44 24 08 48 8b 87 d8 00
      00 00 48 c7 c7 30 db 91 81 48 89 04 24 31 c0 e8 4f a8 0e 00 <0f> 0b
      eb fe 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 48 83
RIP  [] skb_put+0xa1/0xb0
RSP 
Kernel panic - not syncing: Fatal exception

Moreover, the possible minimum is 1, so we can get another kernel panic:
...
BUG: unable to handle kernel paging request at ffff88013caee5c0
IP: [] __alloc_skb+0x12f/0x1f0
...

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

net: reject creation of netdev names with colons

2015-03-18T12:22:27+00:00

[ Upstream commit a4176a9391868bfa87705bcd2e3b49e9b9dd2996 ]

colons are used as a separator in netdev device lookup in dev_ioctl.c

Specific functions are SIOCGIFTXQLEN SIOCETHTOOL SIOCSIFNAME

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

gen_stats.c: Duplicate xstats buffer for later use

2015-03-18T12:22:26+00:00

[ Upstream commit 1c4cff0cf55011792125b6041bc4e9713e46240f ]

The gnet_stats_copy_app() function gets called, more often than not, with its
second argument a pointer to an automatic variable in the caller's stack.
Therefore, to avoid copying garbage afterwards when calling
gnet_stats_finish_copy(), this data is better copied to a dynamically allocated
memory that gets freed after use.

[xiyou.wangcong@gmail.com: remove a useless kfree()]

Signed-off-by: Ignacy Gawędzki 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: call ->dellink on failure when ->newlink exists

2015-03-18T12:22:26+00:00

[ Upstream commit 7afb8886a05be68e376655539a064ec672de8a8e ]

Ignacy reported that when eth0 is down and add a vlan device
on top of it like:

  ip link add link eth0 name eth0.1 up type vlan id 1

We will get a refcount leak:

  unregister_netdevice: waiting for eth0.1 to become free. Usage count = 2

The problem is when rtnl_configure_link() fails in rtnl_newlink(),
we simply call unregister_device(), but for stacked device like vlan,
we almost do nothing when we unregister the upper device, more work
is done when we unregister the lower device, so call its ->dellink().

Reported-by: Ignacy Gawedzki 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: ifla_vf_policy: fix misuses of NLA_BINARY

2015-03-18T12:22:25+00:00

[ Upstream commit 364d5716a7adb91b731a35765d369602d68d2881 ]

ifla_vf_policy[] is wrong in advertising its individual member types as
NLA_BINARY since .type = NLA_BINARY in combination with .len declares the
len member as *max* attribute length [0, len].

The issue is that when do_setvfinfo() is being called to set up a VF
through ndo handler, we could set corrupted data if the attribute length
is less than the size of the related structure itself.

The intent is exactly the opposite, namely to make sure to pass at least
data of minimum size of len.

Fixes: ebc08a6f47ee ("rtnetlink: Add VF config code to rtnetlink")
Cc: Mitch Williams 
Cc: Jeff Kirsher 
Signed-off-by: Daniel Borkmann 
Acked-by: Thomas Graf 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: dont send notification when skb->len == 0 in rtnl_bridge_notify

2015-02-27T01:48:48+00:00

[ Upstream commit 59ccaaaa49b5b096cdc1f16706a9f931416b2332 ]

Reported in: https://bugzilla.kernel.org/show_bug.cgi?id=92081

This patch avoids calling rtnl_notify if the device ndo_bridge_getlink
handler does not return any bytes in the skb.

Alternately, the skb->len check can be moved inside rtnl_notify.

For the bridge vlan case described in 92081, there is also a fix needed
in bridge driver to generate a proper notification. Will fix that in
subsequent patch.

v2: rebase patch on net tree

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

net: rps: fix cpu unplug

2015-02-27T01:48:47+00:00

[ Upstream commit ac64da0b83d82abe62f78b3d0e21cca31aea24fa ]

softnet_data.input_pkt_queue is protected by a spinlock that
we must hold when transferring packets from victim queue to an active
one. This is because other cpus could still be trying to enqueue packets
into victim queue.

A second problem is that when we transfert the NAPI poll_list from
victim to current cpu, we absolutely need to special case the percpu
backlog, because we do not want to add complex locking to protect
process_queue : Only owner cpu is allowed to manipulate it, unless cpu
is offline.

Based on initial patch from Prasad Sodagudi & Subash Abhinov
Kasiviswanathan.

This version is better because we do not slow down packet processing,
only make migration safer.

Reported-by: Prasad Sodagudi 
Reported-by: Subash Abhinov Kasiviswanathan 
Signed-off-by: Eric Dumazet 
Cc: Tom Herbert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: release net refcnt on error in do_setlink()

2014-12-16T17:09:42+00:00

[ Upstream commit e0ebde0e131b529fd721b24f62872def5ec3718c ]

rtnl_link_get_net() holds a reference on the 'struct net', we need to release
it in case of error.

CC: Eric W. Biederman 
Fixes: b51642f6d77b ("net: Enable a userns root rtnl calls that are safe for unprivilged users")
Signed-off-by: Nicolas Dichtel 
Reviewed-by: "Eric W. Biederman" 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

iovec: make sure the caller actually wants anything in memcpy_fromiovecend

2014-08-14T01:24:15+00:00

[ Upstream commit 06ebb06d49486676272a3c030bfeef4bd969a8e6 ]

Check for cases when the caller requests 0 bytes instead of running off
and dereferencing potentially invalid iovecs.

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

net: Correctly set segment mac_len in skb_segment().

2014-08-14T01:24:15+00:00

[ Upstream commit fcdfe3a7fa4cb74391d42b6a26dc07c20dab1d82 ]

When performing segmentation, the mac_len value is copied right
out of the original skb.  However, this value is not always set correctly
(like when the packet is VLAN-tagged) and we'll end up copying a bad
value.

One way to demonstrate this is to configure a VM which tags
packets internally and turn off VLAN acceleration on the forwarding
bridge port.  The packets show up corrupt like this:
16:18:24.985548 52:54:00:ab:be:25 > 52:54:00:26:ce:a3, ethertype 802.1Q
(0x8100), length 1518: vlan 100, p 0, ethertype 0x05e0,
        0x0000:  8cdb 1c7c 8cdb 0064 4006 b59d 0a00 6402 ...|...d@.....d.
        0x0010:  0a00 6401 9e0d b441 0a5e 64ec 0330 14fa ..d....A.^d..0..
        0x0020:  29e3 01c9 f871 0000 0101 080a 000a e833)....q.........3
        0x0030:  000f 8c75 6e65 7470 6572 6600 6e65 7470 ...unetperf.netp
        0x0040:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        0x0050:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        0x0060:  6572 6600 6e65 7470 6572 6600 6e65 7470 erf.netperf.netp
        ...

This also leads to awful throughput as GSO packets are dropped and
cause retransmissions.

The solution is to set the mac_len using the values already available
in then new skb.  We've already adjusted all of the header offset, so we
might as well correctly figure out the mac_len using skb_reset_mac_len().
After this change, packets are segmented correctly and performance
is restored.

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