From: Johannes Berg <johannes.b...@intel.com>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit c30bc94758ae2a38a5eb31767c1985c0aae0950b upstream.

L2TP for example uses NLA_MSECS like this:
policy:
        [L2TP_ATTR_RECV_TIMEOUT]        = { .type = NLA_MSECS, },
code:
        if (info->attrs[L2TP_ATTR_RECV_TIMEOUT])
                cfg.reorder_timeout = 
nla_get_msecs(info->attrs[L2TP_ATTR_RECV_TIMEOUT]);

As nla_get_msecs() is essentially nla_get_u64() plus the
conversion to a HZ-based value, this will not properly
reject attributes from userspace that aren't long enough
and might overrun the message.

Add NLA_MSECS to the attribute minlen array to check the
size properly.

Cc: Thomas Graf <tg...@suug.ch>
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortma...@windriver.com>
---
 lib/nlattr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/nlattr.c b/lib/nlattr.c
index c4706eb..109d4fe 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -20,6 +20,7 @@ static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
        [NLA_U16]       = sizeof(u16),
        [NLA_U32]       = sizeof(u32),
        [NLA_U64]       = sizeof(u64),
+       [NLA_MSECS]     = sizeof(u64),
        [NLA_NESTED]    = NLA_HDRLEN,
 };
 
-- 
1.7.12.rc2

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