aboutsummaryrefslogtreecommitdiff
path: root/net/ipv6
diff options
context:
space:
mode:
authorLinus Lüssing <linus.luessing@c0d3.blue>2019-01-21 07:26:26 +0100
committerDavid S. Miller <davem@davemloft.net>2019-01-22 17:18:08 -0800
commita2e2ca3bebe273055a212d754ffe4e0264192d74 (patch)
tree7e67a61e9eafae3581f2995fbc54b65aacd72f8c /net/ipv6
parentba5ea614622dca6d675b4cc8a97270569ae13a23 (diff)
downloadlinux-stericsson-a2e2ca3bebe273055a212d754ffe4e0264192d74.tar.gz
bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() internals
With this patch the internal use of the skb_trimmed is reduced to the ICMPv6/IGMP checksum verification. And for the length checks the newly introduced helper functions are used instead of calculating and checking with skb->len directly. These changes should hopefully make it easier to verify that length checks are performed properly. Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
-rw-r--r--net/ipv6/mcast_snoop.c62
1 files changed, 30 insertions, 32 deletions
diff --git a/net/ipv6/mcast_snoop.c b/net/ipv6/mcast_snoop.c
index 1a917dc80d5e..a72ddfc40eb3 100644
--- a/net/ipv6/mcast_snoop.c
+++ b/net/ipv6/mcast_snoop.c
@@ -77,27 +77,27 @@ static int ipv6_mc_check_mld_reportv2(struct sk_buff *skb)
len += sizeof(struct mld2_report);
- return pskb_may_pull(skb, len) ? 0 : -EINVAL;
+ return ipv6_mc_may_pull(skb, len) ? 0 : -EINVAL;
}
static int ipv6_mc_check_mld_query(struct sk_buff *skb)
{
+ unsigned int transport_len = ipv6_transport_len(skb);
struct mld_msg *mld;
- unsigned int len = skb_transport_offset(skb);
+ unsigned int len;
/* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL))
return -EINVAL;
- len += sizeof(struct mld_msg);
- if (skb->len < len)
- return -EINVAL;
-
/* MLDv1? */
- if (skb->len != len) {
+ if (transport_len != sizeof(struct mld_msg)) {
/* or MLDv2? */
- len += sizeof(struct mld2_query) - sizeof(struct mld_msg);
- if (skb->len < len || !pskb_may_pull(skb, len))
+ if (transport_len < sizeof(struct mld2_query))
+ return -EINVAL;
+
+ len = skb_transport_offset(skb) + sizeof(struct mld2_query);
+ if (!ipv6_mc_may_pull(skb, len))
return -EINVAL;
}
@@ -115,7 +115,13 @@ static int ipv6_mc_check_mld_query(struct sk_buff *skb)
static int ipv6_mc_check_mld_msg(struct sk_buff *skb)
{
- struct mld_msg *mld = (struct mld_msg *)skb_transport_header(skb);
+ unsigned int len = skb_transport_offset(skb) + sizeof(struct mld_msg);
+ struct mld_msg *mld;
+
+ if (!ipv6_mc_may_pull(skb, len))
+ return -EINVAL;
+
+ mld = (struct mld_msg *)skb_transport_header(skb);
switch (mld->mld_type) {
case ICMPV6_MGM_REDUCTION:
@@ -136,36 +142,24 @@ static inline __sum16 ipv6_mc_validate_checksum(struct sk_buff *skb)
return skb_checksum_validate(skb, IPPROTO_ICMPV6, ip6_compute_pseudo);
}
-static int __ipv6_mc_check_mld(struct sk_buff *skb)
-
+static int ipv6_mc_check_icmpv6(struct sk_buff *skb)
{
- struct sk_buff *skb_chk = NULL;
- unsigned int transport_len;
- unsigned int len = skb_transport_offset(skb) + sizeof(struct mld_msg);
- int ret = -EINVAL;
+ unsigned int len = skb_transport_offset(skb) + sizeof(struct icmp6hdr);
+ unsigned int transport_len = ipv6_transport_len(skb);
+ struct sk_buff *skb_chk;
- transport_len = ntohs(ipv6_hdr(skb)->payload_len);
- transport_len -= skb_transport_offset(skb) - sizeof(struct ipv6hdr);
+ if (!ipv6_mc_may_pull(skb, len))
+ return -EINVAL;
skb_chk = skb_checksum_trimmed(skb, transport_len,
ipv6_mc_validate_checksum);
if (!skb_chk)
- goto err;
-
- if (!pskb_may_pull(skb_chk, len))
- goto err;
-
- ret = ipv6_mc_check_mld_msg(skb_chk);
- if (ret)
- goto err;
-
- ret = 0;
+ return -EINVAL;
-err:
- if (skb_chk && skb_chk != skb)
+ if (skb_chk != skb)
kfree_skb(skb_chk);
- return ret;
+ return 0;
}
/**
@@ -195,6 +189,10 @@ int ipv6_mc_check_mld(struct sk_buff *skb)
if (ret < 0)
return ret;
- return __ipv6_mc_check_mld(skb);
+ ret = ipv6_mc_check_icmpv6(skb);
+ if (ret < 0)
+ return ret;
+
+ return ipv6_mc_check_mld_msg(skb);
}
EXPORT_SYMBOL(ipv6_mc_check_mld);