From: Johannes Berg <johannes@sipsolutions.net>
Date: Fri, 23 Mar 2007 18:37:48 +0000 (-0700)
Subject: [NETLINK]: introduce NLA_BINARY type
X-Git-Tag: v2.6.22-rc1~1128^2~165
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d30045a0bcf144753869175dd9d840f7ceaf4aba;p=linux-2.6

[NETLINK]: introduce NLA_BINARY type

This patch introduces a new NLA_BINARY attribute policy type with the
verification of simply checking the maximum length of the payload.

It also fixes a small typo in the example.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 1c11518fc8..2e4c90a98a 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -171,6 +171,7 @@ enum {
 	NLA_MSECS,
 	NLA_NESTED,
 	NLA_NUL_STRING,
+	NLA_BINARY,
 	__NLA_TYPE_MAX,
 };
 
@@ -188,12 +189,13 @@ enum {
  *    NLA_STRING           Maximum length of string
  *    NLA_NUL_STRING       Maximum length of string (excluding NUL)
  *    NLA_FLAG             Unused
+ *    NLA_BINARY           Maximum length of attribute payload
  *    All other            Exact length of attribute payload
  *
  * Example:
  * static struct nla_policy my_policy[ATTR_MAX+1] __read_mostly = {
  * 	[ATTR_FOO] = { .type = NLA_U16 },
- *	[ATTR_BAR] = { .type = NLA_STRING, len = BARSIZ },
+ *	[ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ },
  *	[ATTR_BAZ] = { .len = sizeof(struct mystruct) },
  * };
  */
diff --git a/net/netlink/attr.c b/net/netlink/attr.c
index 004139557e..df5f820a4c 100644
--- a/net/netlink/attr.c
+++ b/net/netlink/attr.c
@@ -67,6 +67,11 @@ static int validate_nla(struct nlattr *nla, int maxtype,
 		}
 		break;
 
+	case NLA_BINARY:
+		if (pt->len && attrlen > pt->len)
+			return -ERANGE;
+		break;
+
 	default:
 		if (pt->len)
 			minlen = pt->len;