netrom: avoid overflows in nr_setsockopt()

Check setsockopt arguments to avoid overflows and return -EINVAL for
too large arguments.

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index c329b474eace252d34750b70bec598589d21b61e..7dab229bfbcca3c67aa6112ec4a19a40c411adcb 100644 (file)
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -306,26 +306,26 @@ static int nr_setsockopt(struct socket *sock, int level, int optname,
 {
        struct sock *sk = sock->sk;
        struct nr_sock *nr = nr_sk(sk);
-       int opt;
+       unsigned long opt;
 
        if (level != SOL_NETROM)
                return -ENOPROTOOPT;
 
-       if (optlen < sizeof(int))
+       if (optlen < sizeof(unsigned int))
                return -EINVAL;
 
-       if (get_user(opt, (int __user *)optval))
+       if (get_user(opt, (unsigned int __user *)optval))
                return -EFAULT;
 
        switch (optname) {
        case NETROM_T1:
-               if (opt < 1)
+               if (opt < 1 || opt > ULONG_MAX / HZ)
                        return -EINVAL;
                nr->t1 = opt * HZ;
                return 0;
 
        case NETROM_T2:
-               if (opt < 1)
+               if (opt < 1 || opt > ULONG_MAX / HZ)
                        return -EINVAL;
                nr->t2 = opt * HZ;
                return 0;
@@ -337,13 +337,13 @@ static int nr_setsockopt(struct socket *sock, int level, int optname,
                return 0;
 
        case NETROM_T4:
-               if (opt < 1)
+               if (opt < 1 || opt > ULONG_MAX / HZ)
                        return -EINVAL;
                nr->t4 = opt * HZ;
                return 0;
 
        case NETROM_IDLE:
-               if (opt < 0)
+               if (opt > ULONG_MAX / (60 * HZ))
                        return -EINVAL;
                nr->idle = opt * 60 * HZ;
                return 0;