linux-toradex.git/net/ipv4, branch v2.6.38.6

ip: ip_options_compile() resilient to NULL skb route

2011-04-21T21:33:00+00:00

commit c65353daf137dd41f3ede3baf62d561fca076228 upstream.

Scot Doyle demonstrated ip_options_compile() could be called with an skb
without an attached route, using a setup involving a bridge, netfilter,
and forged IP packets.

Let's make ip_options_compile() and ip_options_rcv_srr() a bit more
robust, instead of changing bridge/netfilter code.

With help from Hiroaki SHIMODA.

Reported-by: Scot Doyle 
Tested-by: Scot Doyle 
Signed-off-by: Eric Dumazet 
Cc: Stephen Hemminger 
Acked-by: Hiroaki SHIMODA 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: avoid cwnd moderation in undo

2011-04-21T21:32:33+00:00

[ Upstream commit 67d4120a1793138bc9f4a6eb61d0fc5298ed97e0 ]

In the current undo logic, cwnd is moderated after it was restored
to the value prior entering fast-recovery. It was moderated first
in tcp_try_undo_recovery then again in tcp_complete_cwr.

Since the undo indicates recovery was false, these moderations
are not necessary. If the undo is triggered when most of the
outstanding data have been acknowledged, the (restored) cwnd is
falsely pulled down to a small value.

This patch removes these cwnd moderations if cwnd is undone
  a) during fast-recovery
	b) by receiving DSACKs past fast-recovery

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

net_sched: fix ip_tos2prio

2011-04-21T21:32:28+00:00

[ Upstream commit 4a2b9c3756077c05dd8666e458a751d2248b61b6 ]

ECN support incorrectly maps ECN BESTEFFORT packets to TC_PRIO_FILLER
(1) instead of TC_PRIO_BESTEFFORT (0)

This means ECN enabled flows are placed in pfifo_fast/prio low priority
band, giving ECN enabled flows [ECT(0) and CE codepoints] higher drop
probabilities.

This is rather unfortunate, given we would like ECN being more widely
used.

Ref : http://www.coverfire.com/archives/2011/03/13/pfifo_fast-and-ecn/

Signed-off-by: Dan Siemon 
Signed-off-by: Eric Dumazet 
Cc: Dave Täht 
Cc: Jonathan Morton 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

fib: add rtnl locking in ip_fib_net_exit

2011-04-21T21:32:26+00:00

[ Upstream commit e2666f84958adb3a034b98e99699b55705117e01 ]

Daniel J Blueman reported a lockdep splat in trie_firstleaf(), caused by
RTNL being not locked before a call to fib_table_flush()

Reported-by: Daniel J Blueman 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

netfilter: ipt_CLUSTERIP: fix buffer overflow

2011-04-14T20:02:32+00:00

commit 961ed183a9fd080cf306c659b8736007e44065a5 upstream.

'buffer' string is copied from userspace.  It is not checked whether it is
zero terminated.  This may lead to overflow inside of simple_strtoul().
Changli Gao suggested to copy not more than user supplied 'size' bytes.

It was introduced before the git epoch.  Files "ipt_CLUSTERIP/*" are
root writable only by default, however, on some setups permissions might be
relaxed to e.g. network admin user.

Signed-off-by: Vasiliy Kulikov 
Acked-by: Changli Gao 
Signed-off-by: Patrick McHardy 
Signed-off-by: Greg Kroah-Hartman

netfilter: arp_tables: fix infoleak to userspace

2011-04-14T20:02:32+00:00

commit 42eab94fff18cb1091d3501cd284d6bd6cc9c143 upstream.

Structures ipt_replace, compat_ipt_replace, and xt_get_revision are
copied from userspace.  Fields of these structs that are
zero-terminated strings are not checked.  When they are used as argument
to a format string containing "%s" in request_module(), some sensitive
information is leaked to userspace via argument of spawned modprobe
process.

The first bug was introduced before the git epoch;  the second is
introduced by 6b7d31fc (v2.6.15-rc1);  the third is introduced by
6b7d31fc (v2.6.15-rc1).  To trigger the bug one should have
CAP_NET_ADMIN.

Signed-off-by: Vasiliy Kulikov 
Signed-off-by: Patrick McHardy 
Signed-off-by: Greg Kroah-Hartman

netfilter: xtables: fix reentrancy

2011-04-14T20:02:31+00:00

commit db856674ac69e31946e56085239757cca3f7655f upstream.

commit f3c5c1bfd4308 (make ip_tables reentrant) introduced a race in
handling the stackptr restore, at the end of ipt_do_table()

We should do it before the call to xt_info_rdunlock_bh(), or we allow
cpu preemption and another cpu overwrites stackptr of original one.

A second fix is to change the underflow test to check the origptr value
instead of 0 to detect underflow, or else we allow a jump from different
hooks.

Signed-off-by: Eric Dumazet 
Cc: Jan Engelhardt 
Signed-off-by: Patrick McHardy 
Signed-off-by: Greg Kroah-Hartman

netfilter: ip_tables: fix infoleak to userspace

2011-04-14T20:02:31+00:00

commit 78b79876761b86653df89c48a7010b5cbd41a84a upstream.

Structures ipt_replace, compat_ipt_replace, and xt_get_revision are
copied from userspace.  Fields of these structs that are
zero-terminated strings are not checked.  When they are used as argument
to a format string containing "%s" in request_module(), some sensitive
information is leaked to userspace via argument of spawned modprobe
process.

The first and the third bugs were introduced before the git epoch; the
second was introduced in 2722971c (v2.6.17-rc1).  To trigger the bug
one should have CAP_NET_ADMIN.

Signed-off-by: Vasiliy Kulikov 
Signed-off-by: Patrick McHardy 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'master' of /home/davem/src/GIT/linux-2.6/

2011-03-10T22:00:44+00:00

net: don't allow CAP_NET_ADMIN to load non-netdev kernel modules

2011-03-09T23:25:19+00:00

Since a8f80e8ff94ecba629542d9b4b5f5a8ee3eb565c any process with
CAP_NET_ADMIN may load any module from /lib/modules/.  This doesn't mean
that CAP_NET_ADMIN is a superset of CAP_SYS_MODULE as modules are
limited to /lib/modules/**.  However, CAP_NET_ADMIN capability shouldn't
allow anybody load any module not related to networking.

This patch restricts an ability of autoloading modules to netdev modules
with explicit aliases.  This fixes CVE-2011-1019.

Arnd Bergmann suggested to leave untouched the old pre-v2.6.32 behavior
of loading netdev modules by name (without any prefix) for processes
with CAP_SYS_MODULE to maintain the compatibility with network scripts
that use autoloading netdev modules by aliases like "eth0", "wlan0".

Currently there are only three users of the feature in the upstream
kernel: ipip, ip_gre and sit.

    root@albatros:~# capsh --drop=$(seq -s, 0 11),$(seq -s, 13 34) --
    root@albatros:~# grep Cap /proc/$$/status
    CapInh:	0000000000000000
    CapPrm:	fffffff800001000
    CapEff:	fffffff800001000
    CapBnd:	fffffff800001000
    root@albatros:~# modprobe xfs
    FATAL: Error inserting xfs
    (/lib/modules/2.6.38-rc6-00001-g2bf4ca3/kernel/fs/xfs/xfs.ko): Operation not permitted
    root@albatros:~# lsmod | grep xfs
    root@albatros:~# ifconfig xfs
    xfs: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep xfs
    root@albatros:~# lsmod | grep sit
    root@albatros:~# ifconfig sit
    sit: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep sit
    root@albatros:~# ifconfig sit0
    sit0      Link encap:IPv6-in-IPv4
	      NOARP  MTU:1480  Metric:1

    root@albatros:~# lsmod | grep sit
    sit                    10457  0
    tunnel4                 2957  1 sit

For CAP_SYS_MODULE module loading is still relaxed:

    root@albatros:~# grep Cap /proc/$$/status
    CapInh:	0000000000000000
    CapPrm:	ffffffffffffffff
    CapEff:	ffffffffffffffff
    CapBnd:	ffffffffffffffff
    root@albatros:~# ifconfig xfs
    xfs: error fetching interface information: Device not found
    root@albatros:~# lsmod | grep xfs
    xfs                   745319  0

Reference: https://lkml.org/lkml/2011/2/24/203

Signed-off-by: Vasiliy Kulikov 
Signed-off-by: Michael Tokarev 
Acked-by: David S. Miller 
Acked-by: Kees Cook 
Signed-off-by: James Morris