Linux 2.6.20.19

Linux 2.6.20.19

[Willy Tarreau]

I've just released Linux 2.6.20.19.

It backports a fix present in 2.6.22 for a bug introduced in the IPv6
stack in 2.6.20, which could lead to crashes under certain circumstances.

I'll also be replying to this message with a copy of the patch between
2.6.20.18 and 2.6.20.19.

The patch and changelog will appear soon at the following locations:
  ftp://ftp.all.kernel.org/pub/linux/kernel/v2.6/
  ftp://ftp.all.kernel.org/pub/linux/kernel/v2.6/patch-2.6.20.19.bz2
  ftp://ftp.all.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.20.19

Git repository:
   git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-2.6.20.y.git
  http://www.kernel.org/pub/scm/linux/kernel/git/stable/linux-2.6.20.y.git

Git repository through the gitweb interface:
  http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.20.y.git

Willy

-------

 Makefile           |    2 +-
 net/ipv6/exthdrs.c |   16 ++++++++++++----
 2 files changed, 13 insertions(+), 5 deletions(-)

Summary of changes from 2.6.20.18 to 2.6.20.19
============================================

Willy Tarreau (1):
      Linux 2.6.20.19

YOSHIFUJI Hideaki (1):
      [IPV6]: Do no rely on skb->dst before it is assigned.

Re: Linux 2.6.20.19

[Willy Tarreau]

diff --git a/Makefile b/Makefile
index 48daec7..6bb9f2e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 VERSION = 2
 PATCHLEVEL = 6
 SUBLEVEL = 20
-EXTRAVERSION = .18
+EXTRAVERSION = .19
 NAME = Homicidal Dwarf Hamster
 
 # *DOCUMENTATION*
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index de96e1a..82a3444 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -653,6 +653,14 @@ EXPORT_SYMBOL_GPL(ipv6_invert_rthdr);
   Hop-by-hop options.
  **********************************/
 
+/*
+ * Note: we cannot rely on skb->dst before we assign it in ip6_route_input().
+ */
+static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
+{
+	return skb->dst ? ip6_dst_idev(skb->dst) : __in6_dev_get(skb->dev);
+}
+
 /* Router Alert as of RFC 2711 */
 
 static int ipv6_hop_ra(struct sk_buff **skbp, int optoff)
@@ -679,25 +687,25 @@ static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff)
 	if (skb->nh.raw[optoff+1] != 4 || (optoff&3) != 2) {
 		LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
 		               skb->nh.raw[optoff+1]);
-		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
+		IP6_INC_STATS_BH(ipv6_skb_idev(skb),
 				 IPSTATS_MIB_INHDRERRORS);
 		goto drop;
 	}
 
 	pkt_len = ntohl(*(__be32*)(skb->nh.raw+optoff+2));
 	if (pkt_len <= IPV6_MAXPLEN) {
-		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
+		IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS);
 		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
 		return 0;
 	}
 	if (skb->nh.ipv6h->payload_len) {
-		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
+		IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INHDRERRORS);
 		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
 		return 0;
 	}
 
 	if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
-		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INTRUNCATEDPKTS);
+		IP6_INC_STATS_BH(ipv6_skb_idev(skb), IPSTATS_MIB_INTRUNCATEDPKTS);
 		goto drop;
 	}