1 files changed, 58 insertions, 8 deletions

diff --git a/lib/nlattr.c b/lib/nlattr.c
index a7e0b16078df..3d8295c85505 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * NETLINK      Netlink attributes
  *
@@ -27,6 +28,30 @@ static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = {
 	[NLA_S64]	= sizeof(s64),
 };
 
+static int validate_nla_bitfield32(const struct nlattr *nla,
+				   u32 *valid_flags_allowed)
+{
+	const struct nla_bitfield32 *bf = nla_data(nla);
+	u32 *valid_flags_mask = valid_flags_allowed;
+
+	if (!valid_flags_allowed)
+		return -EINVAL;
+
+	/*disallow invalid bit selector */
+	if (bf->selector & ~*valid_flags_mask)
+		return -EINVAL;
+
+	/*disallow invalid bit values */
+	if (bf->value & ~*valid_flags_mask)
+		return -EINVAL;
+
+	/*disallow valid bit values that are not selected*/
+	if (bf->value & ~bf->selector)
+		return -EINVAL;
+
+	return 0;
+}
+
 static int validate_nla(const struct nlattr *nla, int maxtype,
 			const struct nla_policy *policy)
 {
@@ -46,6 +71,12 @@ static int validate_nla(const struct nlattr *nla, int maxtype,
 			return -ERANGE;
 		break;
 
+	case NLA_BITFIELD32:
+		if (attrlen != sizeof(struct nla_bitfield32))
+			return -ERANGE;
+
+		return validate_nla_bitfield32(nla, pt->validation_data);
+
 	case NLA_NUL_STRING:
 		if (pt->len)
 			minlen = min_t(int, attrlen, pt->len + 1);
@@ -272,6 +303,30 @@ size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
 EXPORT_SYMBOL(nla_strlcpy);
 
 /**
+ * nla_strdup - Copy string attribute payload into a newly allocated buffer
+ * @nla: attribute to copy the string from
+ * @flags: the type of memory to allocate (see kmalloc).
+ *
+ * Returns a pointer to the allocated buffer or NULL on error.
+ */
+char *nla_strdup(const struct nlattr *nla, gfp_t flags)
+{
+	size_t srclen = nla_len(nla);
+	char *src = nla_data(nla), *dst;
+
+	if (srclen > 0 && src[srclen - 1] == '\0')
+		srclen--;
+
+	dst = kmalloc(srclen + 1, flags);
+	if (dst != NULL) {
+		memcpy(dst, src, srclen);
+		dst[srclen] = '\0';
+	}
+	return dst;
+}
+EXPORT_SYMBOL(nla_strdup);
+
+/**
  * nla_memcpy - Copy a netlink attribute into another memory area
  * @dest: where to copy to memcpy
  * @src: netlink attribute to copy from
@@ -352,7 +407,7 @@ struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
 {
 	struct nlattr *nla;
 
-	nla = (struct nlattr *) skb_put(skb, nla_total_size(attrlen));
+	nla = skb_put(skb, nla_total_size(attrlen));
 	nla->nla_type = attrtype;
 	nla->nla_len = nla_attr_size(attrlen);
 
@@ -398,12 +453,7 @@ EXPORT_SYMBOL(__nla_reserve_64bit);
  */
 void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
 {
-	void *start;
-
-	start = skb_put(skb, NLA_ALIGN(attrlen));
-	memset(start, 0, NLA_ALIGN(attrlen));
-
-	return start;
+	return skb_put_zero(skb, NLA_ALIGN(attrlen));
 }
 EXPORT_SYMBOL(__nla_reserve_nohdr);
 
@@ -617,7 +667,7 @@ int nla_append(struct sk_buff *skb, int attrlen, const void *data)
 	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
 		return -EMSGSIZE;
 
-	memcpy(skb_put(skb, attrlen), data, attrlen);
+	skb_put_data(skb, data, attrlen);
 	return 0;
 }
 EXPORT_SYMBOL(nla_append);