[IPV6]: Check length of int/boolean optval provided by user in setsockopt().

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index bd3fb12..2f1244d 100644 (file)
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -16,7 +16,6 @@
  *
  *     FIXME: Make the setsockopt code POSIX compliant: That is
  *
- *     o       Return -EINVAL for setsockopt of short lengths
  *     o       Truncate getsockopt returns
  *     o       Return an optlen of the truncated length if need be
  *
@@ -114,8 +113,13 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 
        if (optval == NULL)
                val=0;
-       else if (get_user(val, (int __user *) optval))
-               return -EFAULT;
+       else {
+               if (optlen >= sizeof(int)) {
+                       if (get_user(val, (int __user *) optval))
+                               return -EFAULT;
+               } else
+                       val = 0;
+       }
 
        valbool = (val!=0);
 
@@ -127,6 +131,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
        switch (optname) {
 
        case IPV6_ADDRFORM:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val == PF_INET) {
                        struct ipv6_txoptions *opt;
                        struct sk_buff *pktopt;
@@ -201,63 +207,86 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
                goto e_inval;
 
        case IPV6_V6ONLY:
-               if (inet_sk(sk)->num)
+               if (optlen < sizeof(int) ||
+                   inet_sk(sk)->num)
                        goto e_inval;
                np->ipv6only = valbool;
                retv = 0;
                break;
 
        case IPV6_RECVPKTINFO:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxinfo = valbool;
                retv = 0;
                break;
 
        case IPV6_2292PKTINFO:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxoinfo = valbool;
                retv = 0;
                break;
 
        case IPV6_RECVHOPLIMIT:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxhlim = valbool;
                retv = 0;
                break;
 
        case IPV6_2292HOPLIMIT:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxohlim = valbool;
                retv = 0;
                break;
 
        case IPV6_RECVRTHDR:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.srcrt = valbool;
                retv = 0;
                break;
 
        case IPV6_2292RTHDR:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.osrcrt = valbool;
                retv = 0;
                break;
 
        case IPV6_RECVHOPOPTS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.hopopts = valbool;
                retv = 0;
                break;
 
        case IPV6_2292HOPOPTS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.ohopopts = valbool;
                retv = 0;
                break;
 
        case IPV6_RECVDSTOPTS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.dstopts = valbool;
                retv = 0;
                break;
 
        case IPV6_2292DSTOPTS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.odstopts = valbool;
                retv = 0;
                break;
 
        case IPV6_TCLASS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val < -1 || val > 0xff)
                        goto e_inval;
                np->tclass = val;
@@ -265,11 +294,15 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
                break;
 
        case IPV6_RECVTCLASS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxtclass = valbool;
                retv = 0;
                break;
 
        case IPV6_FLOWINFO:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->rxopt.bits.rxflow = valbool;
                retv = 0;
                break;
@@ -288,9 +321,9 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
                if (optname != IPV6_RTHDR && !capable(CAP_NET_RAW))
                        break;
 
-               retv = -EINVAL;
-               if (optlen & 0x7 || optlen > 8 * 255)
-                       break;
+               if (optlen < sizeof(struct ipv6_opt_hdr) ||
+                   optlen & 0x7 || optlen > 8 * 255)
+                       goto e_inval;
 
                opt = ipv6_renew_options(sk, np->opt, optname,
                                         (struct ipv6_opt_hdr __user *)optval,
@@ -408,6 +441,8 @@ done:
                break;
        }
        case IPV6_UNICAST_HOPS:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val > 255 || val < -1)
                        goto e_inval;
                np->hop_limit = val;
@@ -417,6 +452,8 @@ done:
        case IPV6_MULTICAST_HOPS:
                if (sk->sk_type == SOCK_STREAM)
                        goto e_inval;
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val > 255 || val < -1)
                        goto e_inval;
                np->mcast_hops = val;
@@ -424,6 +461,8 @@ done:
                break;
 
        case IPV6_MULTICAST_LOOP:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->mc_loop = valbool;
                retv = 0;
                break;
@@ -431,6 +470,8 @@ done:
        case IPV6_MULTICAST_IF:
                if (sk->sk_type == SOCK_STREAM)
                        goto e_inval;
+               if (optlen < sizeof(int))
+                       goto e_inval;
 
                if (val) {
                        if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
@@ -591,27 +632,37 @@ done:
                break;
        }
        case IPV6_ROUTER_ALERT:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                retv = ip6_ra_control(sk, val, NULL);
                break;
        case IPV6_MTU_DISCOVER:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val<0 || val>3)
                        goto e_inval;
                np->pmtudisc = val;
                retv = 0;
                break;
        case IPV6_MTU:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                if (val && val < IPV6_MIN_MTU)
                        goto e_inval;
                np->frag_size = val;
                retv = 0;
                break;
        case IPV6_RECVERR:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->recverr = valbool;
                if (!val)
                        skb_queue_purge(&sk->sk_error_queue);
                retv = 0;
                break;
        case IPV6_FLOWINFO_SEND:
+               if (optlen < sizeof(int))
+                       goto e_inval;
                np->sndflow = valbool;
                retv = 0;
                break;
@@ -631,6 +682,9 @@ done:
                unsigned int pref = 0;
                unsigned int prefmask = ~0;
 
+               if (optlen < sizeof(int))
+                       goto e_inval;
+
                retv = -EINVAL;
 
                /* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */