ipv6: Fix leak in ipv6_gso_segment().

If ip6_find_1stfragopt() fails and we return an error we have to free
up 'segs' because nobody else is going to.

Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit e3e86b5119f81e5e2499bea7ea1ebe8ac6aab789)

Orabug: 26175248
CVE-2017-9074

Signed-off-by: Kirtikar Kashyap <kirtikar.kashyap@oracle.com>
Reviewed-by: Qing Huang <qing.huang@oracle.com>
Reviewed-by: Jack Vogel <jack.vogel@oracle.com>

diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 2d81319e48a407b126a483878a102d1c39a17c78..a41d0147ceee10ab2c5f445a54b4b79763b15738 100644 (file)
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -122,8 +122,10 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
 
                if (udpfrag) {
                        int err = ip6_find_1stfragopt(skb, &prevhdr);
-                       if (err < 0)
+                       if (err < 0) {
+                               kfree_skb_list(segs);
                                return ERR_PTR(err);
+                       }
                        fptr = (struct frag_hdr *)((u8 *)ipv6h + err);
                        fptr->frag_off = htons(offset);
                        if (skb->next)