diff options
Diffstat (limited to 'net/ipv6/ipv6_sockglue.c')
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 96e3f603c8d8..e4a62ca1a3d0 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -1056,18 +1056,28 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname, break; case MCAST_MSFILTER: { + struct group_filter __user *p = (void __user *)optval; struct group_filter gsf; + const int size0 = offsetof(struct group_filter, gf_slist); + int num; int err; - if (len < GROUP_FILTER_SIZE(0)) + if (len < size0) return -EINVAL; - if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) + if (copy_from_user(&gsf, p, size0)) return -EFAULT; if (gsf.gf_group.ss_family != AF_INET6) return -EADDRNOTAVAIL; + num = gsf.gf_numsrc; lock_sock(sk); - err = ip6_mc_msfget(sk, &gsf, - (struct group_filter __user *)optval, optlen); + err = ip6_mc_msfget(sk, &gsf, p->gf_slist); + if (!err) { + if (num > gsf.gf_numsrc) + num = gsf.gf_numsrc; + if (put_user(GROUP_FILTER_SIZE(num), optlen) || + copy_to_user(p, &gsf, size0)) + err = -EFAULT; + } release_sock(sk); return err; } |